EENNEERRGGEETTIICCSS PPhhDD PPRROOGGRRAAMM … · Areva NP Inc. - Paris Highlights of the research...

Energetics PhD ANNUAL REPORT 2011

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EENNEERRGGEETTIICCSS PPhhDD PPRROOGGRRAAMM

22001111 AANNNNUUAALL RREEPPOORRTT

Editors: L. Savoldi Richard and P. Asinari


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This document contains a series of one-page reports from the students enrolled in 2011 in the

Energetics PhD program at Politecnico di Torino, Italy, including the highlights of their research

activity.

The program is currently managed by a Board, which is composed of the following professors from

Dipartimento Energia (formerly Dipartimento di Energetica):

Pietro Asinari

Marco Badami

Michele Cali’

Gianni Coppa

Mario De Salve

Giovanni Fracastoro

Federico Millo

Antonio Mittica

Nicola Nervegna

Marco Perino

Piero Ravetto

Massimo Santarelli

Laura Savoldi Richard

Ezio Spessa

Vittorio Verda

Roberto Zanino (coordinator)

For additional information please contact [email protected] (+39 011 090 4490).

mailto:[email protected]


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First name: Fabio LAST NAME: ALCARO

Topic: Implementation of quasi-static method for neutron transport

Course year: 3° Tutor(s): Piero Ravetto, Sandra Dulla

Academic context [1] R. Le Tellier, C. Suteau, D. Fournier, J. M. Ruggieri, High-Order DiscreteOrdinate Transport in Hexagonal Geometry: a New Capability in ERANOS, Il Nuovo Cimento C, 33, pp. 121-128 (2010). [2] S. Dulla, E. H. Mund, P. Ravetto, The quasi-static method revisited, Progress in Nuclear Energy, 50, pp. 908-920 (2008). [3] F. Alcaro, S. Dulla, G. Marleau, E. H. Mund, P. Ravetto, Development of Dynamic models for Neutron Transport Calculations, Il Nuovo Cimento C, 33, pp. 13-20 (2010).

External collaborations

CEA Cadarache (France)

Highlights of the research activity

The research activity focused on the implementation of approximate dynamic models for the solution of the time-dependent neutron transport equation. In particular the work has been devoted to the implementation of the quasi-static algorithm into a pre-existing steady-state neutron transport platform developed by the CEA of Cadarache [1]. Two formulations of the quasi-static algorithm have been implemented: The Improved Quasi-static Method (IQM) and the Predictor-Corrector Quasi-static Method (PCQM) [2]. The main accomplishment of the activity has been the development and implementation of a consistent formulation of the quasi-static algorithms, meaning with the former statement that the equations involved have been solved defining the quantities of interest (neutron flux, shape function, external neutron source) on the same functional space, i.e. the phase-space. The approximations introduced in the quasi-static method by the standard kinetic codes are mainly related with the adoption of the scalar flux [3], that affects the calculation process at two different stages: the definition of the pseudo-stationary problem that must be solved in the quasi-static algorithm at first, and the definition of the kinetic parameters appearing in the Point Kinetic equations. The consistent formulation of the quasi-static schemes allows to overcome such issues.

The picture in this section (Figure 1) shows the results that have been obtained for a typical cross-section induced transient for a two-dimensional monokinetic configuration of a critical reactor. The IQM has been adopted, comparing the power profiles of the reactor with different number of time steps. The figure shows a continuous improvement of the final state as the number of time steps increases, a feature that cannot be reproduced when using scalar quantities.

The code is currently capable of performing transient analysis for critical configurations in a multigroup framework, but subcritical configurations fed by external neutron source are in developing phase too, being the latter helpful for the benchmark process of the algorithms themselves.

Figure 1. Power profile resulting from the consistent formulation of the IQM.


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First name: Gabriele LAST NAME: ALTARE

Topic: Energy saving in hydraulic circuits of earth-moving machines

Course year: 2nd Tutor(s): Prof. Nicola Nervegna

Academic context

Earth-moving machines

Fluid Power

Coupled Simulation


Casappa S.p.A.

Merlo S.p.A.


The research activity is focused on energy saving in hydraulic circuits of earth-moving machines. In particular the analysis considers hydraulic systems of excavators and telehandlers. Aim of the research activity is the development of a validated model capable of predicting system behaviour with adequate accuracy in different operating conditions and finding the best energy saving hydraulic configuration. A kinematic analysis to evidence the characteristics of the mechanical system, such as the automatic forks levelling, forks lever ratio and overrunning load conditions is treated as well. Load Sensing circuits of an excavator and of a telehandler of known geometry and components are simulated in AMESim (1D hydraulic code) and Virtual Lab Motion (3D mechanical code). In order to exchange informations between the two codes the hydraulic model is interfaced with the mechanical one that, based on forces consequent to load induced pressures, evaluates in turn velocities and displacements. Interfacing can be done in two different ways: by a co-simulation or by a coupled simulation. In the first one each simulation package runs its own solver, which is synchronised with the other, while in the second the state equations of both AMESim and Motion are solved as a complete set by the Motion simulation solver. This last approach, that allows savings in CPU time and a novel configuration of the hydraulic circuit are the main innovative contributions of the research activity.

Full simulation model of a telehandler


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First name: Salvatore LAST NAME: AMICO

Topic: Development and validation of a predictive combustion model for diesel engines to be implemented in 1D simulation codes (GT-Power)

Course year: 1st Tutor(s): Federico Millo

Academic context [ref 1] Hiroyasu, H., Kadota, T., Arai, M., “Development and use of a spray combustion modeling to predict

Diesel engine efficiency and pollutant emissions”, Bull. JSME 26,214.

[ref 2] Barba, C., Burkhardt, C., Boulouchos, K., and Bargende, M., “A Phenomenological Combustion Model

for Heat Release Rate Prediction in High-Speed DI Diesel Engines with Common Rail Injection,” SAE

Technical Paper 2000-01-2933, 2000, doi:10.4271/2000-01-2933.

[ref 3] Egnell, R., “A Simple Approach to Studying the Relation between Fuel Rate Heat Release Rate and

NO formation in Diesel Engines”, SAE Paper NO. 1999-01-3548, 1999.


GM Powertrain Europe

Highlights of the research activity Nowadays pollutant emission reduction is becoming more and more a constraint in an engine development program. Diesel engine which in the past has established itself due to its lower fuel consumption is called to face a new challenge: lowering emissions without penalizing performance, drivability, noise and, not least, the cost. To this end, several components and new combustion strategies (such as PCCI/HCCI ones) have been developed in the last few years making diesel engine hardware selection very complex. In this framework, simulation plays a significant role as it can aid designer to detect more quickly the engine architecture capable to meet the program requirements thus reducing the number of engine prototypes needed for testing and finally the development timing and cost. For this reason, more and more interest is being paid to develop combustion models capable of predicting performance and pollutant emissions for multiple hardware configurations and combustion strategies. Several approaches have been followed, ranging from simple zero dimensional models up to high sophisticated multi dimensional models. The latter, although give a detailed spatial resolution and fluid motion description, are not yet accurate in capturing phenomena such as turbulence and heat transfer in the chamber. Nevertheless, such models require a significant computational time which makes them not suitable for hardware selection purposes. On the other hand, the assumptions used in the former render that models unsatisfactory for analysis of combustions characterized by high EGR rates coupled to multiple injection events due to their difficult to handle in an effective way long ignition delays and high-premixed heat releases which dominate combustion under such conditions. The fact is that the heterogeneous Diesel combustion nature of direct-injection diesel combustion makes heat-release prediction extremely difficult. Combustion in diesel engine is a three-dimensional, unsteady, two-phases, turbulent phenomena in which a non uniform fluid distribution is achieved due to the chamber motes, chiefly swirl and squish, generated during compression phase. Several process occur and affect diesel combustion: the fuel injection, spray evolution with its physical delay due to fuel evaporation and mixing with fresh air, its chemical delay due to pre-flame reactions, convective and radiation heat transfer and finally turbulent flame reactions. Sufficient knowledge to model all these phenomena is still not at hand and research efforts are being more and more addressed to this goal. To that end, a new predictive diesel combustion model is under development in this PhD activity which, in this first part, has been addressed to evaluate the state-of-the art models capability of predicting engine performance and emissions for a wide range of engine operating conditions. This study has found out that predictive capability of such modeling approaches significantly deteriorates at low-loads in which high EGR rates and low temperature combustions are employed to reduce emissions.


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First name: ANDREA LAST NAME: BARBARINO

Topic: The spectral element approach for the solution of neutron transport problems

Course year: 1st Tutor(s): Prof. S. Dulla, Prof. P. Ravetto

Academic context [1] E.H. Mund, Spectral element solutions for the PN neutron transport equations, Computers & Fluids, 43,

Issue 1, April 2011, Pages 102-106

[2] G. Coppa, P. Ravetto, M. Sumini, The An method and the spherical-harmonics approximation in neutron

transport theory, Annals of Nuclear Energy, 9, Issue 8, 1982, Pages 435-437

[3] B. Rivière, Discontinuous Galerkin Methods for Solving Elliptic and Parabolic Equations: Theory and

Implementation, SIAM, Philadelphia, 2008


Universitè Libre de Bruxelles (ULB) – Prof. E. H. Mund

Arizona University (AME) – Prof. B. Ganapol

Areva NP Inc. - Paris

Highlights of the research activity This PhD activity, supported by Areva Np Inc., is devoted to the study and implementation of an innovative discretization method to address the space dependence of the linear Boltzmann equation for neutrons (LBE), the Spectral Element Method (SEM): it requires an even-parity (second order) formulation of the LBE, and a version developed at Politecnico di Torino is used. The ultimate task is to compute the thermal power distribution in a nuclear reactor. Even if SEM is quite known in the field of fluid-dynamics and structural mechanics, is was never introduced in the field of neutronics, mainly for the limited computing capabilities which hosted the implementation of many state-of-art industrial codes. Nowadays, with improved computing performances and the challenge of high fidelity modeling of nuclear systems (see the CASL initiative, for instance), fine mesh schemes are acquiring greater importance. The first year of activity has been devoted to the implementation of preliminary code samples aimed at demonstrating the superior performance of the SEM method compared to other classical resolution schemes (linear and quadratic FEM, sweep for SN schemes). The numerical properties were evaluated using manufactured solutions in one dimension (some original work has been done in this field due to the inadequateness of literature manufactured solutions). For the two-dimensional analyses, classical benchmark cases were considered. The general variational approach considered at first was the Continuous Galerkin framework, later abandoned in favor of the Discontinuous Galerkin method because of the serious limitations in terms of local refinement of the grid, leading basically to few chances of grid adaptivity. Moreover, with the use of transfinite interpolation of the calculation grid, it has been possible to create involved grids, perfectly suited for lattice (pin level) calculations. At the end of the year it is possible to state with good confidence that SEM guarantees very high convergence rates also with tough solutions, which can happen in nuclear reactors where heterogeneities in cross section appear in a in a limited portion of space. Next years will be devoted to the implementation of the method in three dimensions, with extended benchmark campaigns using the best transport codes available (Eranos, Apollo III).

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Example of transport problem solved SEM:

Natelson benchmark with a non conformal Cartesian grid (normalized values).

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First name: Elisabetta LAST NAME: BOELLA

Topic: Particle acceleration in collisionless shocks1

Course year: 2 Tutor(s): G. Coppa and L.O. Silva

Academic context

[1] D. Haberberger et al., Nat. Phys. advance online publication, (2011). [2] G. Sorasio et al., Phys. Rev. Lett., 96, 45005 (2006). [3] R.A. Fonseca et al., Lecture Notes in Computer Science (Springer-Verlag, Berlin, 2002), Vol.2331, p.342.


Instituto Superior Técnico (Lisbon, Portugal)


Collisionless shocks are non-linear waves that can develop in hot, low-density and fully ionized plasmas. Their thickness is much smaller than the collisional mean free path and, therefore, particle collisions cannot be considered responsible for the sharp transition of the plasma characteristics. The mechanism causing the change of the plasma across the shock is, then, strictly connected to the way in which particles transfer momentum and energy to the electric field (in the case of electrostatic shocks) or to the electromagnetic field (in the case of electromagnetic shocks).

Electrostatic shocks in collisionless plasma play an important role in space physics. They are the cause of ion acceleration in the ionosphere and of precipitating electrons in the aurora acceleration region. Moreover, the importance of electrostatic shocks emerged in the last few years in the field of laser-plasma interaction. In particular, experiments and numerical simulations have shown how a high-quality monoenergetic proton beam, with characteristics suitable for radiotherapy, injectors for conventional accelerators and inertial confinement fusion, can be generated by exciting collisionless electrostatic shocks in laser-produced hydrogen plasma [1].

Being inspired by the previous works of Sorasio et. al. [2] and Fiúza et. al. (not published yet), the purpose of the present research activity is understanding the instabilities that mediate the shock formation. In particular, the study is focused on scenarios characterized by the presence of a hot plasma expanding into a cold region and by the presence of strong density gradients. The comprehension of the optimal parameters to obtain particle acceleration with the suppression of ion acceleration in the sheath is considered to be of great importance.

To reach the goal of this study, numerical simulations are necessary instruments. A new particle-based code, called shell model, is being developed. As a usual Particle-In-Cell code, it uses computational particles to simulate the collective behavior of the plasma, but, since the problem is mainly one dimensional, the use of a fix grid to solve the Poisson equation has been avoided. The technique has been already successfully used to study the expansion of spherical and cylindrical plasmas. Preliminary results show an excellent agreement with reference results obtained with the well-known Osiris code [3].

1 In collaboration with F. Fiúza, A. Stockem and R. Fonseca

Electric field generated by the expansion of a hot plasma into a cold one. Comparison between shell model results (red curve) and Osiris results (black curve).


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First name: Roberto LAST NAME: BONIFETTO

Topic: Modelling for nuclear application

Course year: 1st Tutor(s): Sandra DULLA, Laura SAVOLDI

Academic context [1] R. Bonifetto, A. Kholia, B. Renard, K. Ri e, L. Savoldi Richard and R. Zanino, “Modeling of W7-X superconducting coil cool-down using the 4C code”, Fus. Eng. Des., vol. 86, pp. 1549-1552, 2011. [2] L. Savoldi Richard, F. Casella, B. Fiori and R. Zanino, “The 4C Code for the Cryogenic Circuit Conductor and Coil modeling in ITER", Cryogenics, vol. 50, pp. 167-176, 2010. [3] V. Sobolev, E. Malambu, H. Aït Abderrahim and F. Rosatelli, “Preliminary Fuel Pin and Hexagonal Assembly design (and drawings)”, deliverable of the contract FI6W-2006-036439, October 10, 2007.


Politecnico di Milano (Italy)

KIT (Karlsruhe – Germany)

CEA – Grenoble (France)

ENEA – Bologna (Italy)


In view of the similar geometry and thermal-hydraulic phenomena involved, different components of nuclear fission and fusion devices (see Fig. 1), i.e. molten lead cooled fuel elements and supercritical helium cooled superconducting cables, can be modeled with computational tools having a similar structure. Nuclear fusion applications modelling

Successful conclusion of the validation and benchmark campaign [1] of the Cryogenic Circuit Conductor and Coil (4C) code [2] for the analysis of Thermal-Hydraulic transients in superconducting coils: - Benchmark against CAS code simulation of an ITER TF coil cool-down from 300 K to 80 K; [R. Bonifetto,

F. Buonora, L. Savoldi Richard and R. Zanino, to appear in IEEE Trans. Appl. Supercond. (2012)] - Validation against 80 kA safety discharge in the Toroidal Field Model Coil. [L. Savoldi Richard, R.

Bonifetto, R. Heller and R. Zanino, submitted to IEEE Trans. Plasma Science (2011)]

Development of a new Modelica library for the 4C cryogenic circuit module, successful first validation and benchmark of the tool: - Benchmark of the circuit module against VINCENTA code; [R. Bonifetto, F. Casella, L. Savoldi Richard

and R. Zanino, to appear in Adv. Cryo. Eng. (2012)] - Validation of the circuit module against data from HELIOS facility at

CEA-Grenoble. [R. Zanino, R. Bonifetto, F. Casella and L. Savoldi Richard, submitted to Cryogenics (2011)]

Parallelization of the 2D temperature distribution computation in the 4C code structure module, reducing the computational time of a factor ~2.5.

Application of the 4C code to an ITER design-relevant study of the toroidal field coil safety discharge transient. [L. Savoldi Richard, R. Bonifetto, D. Bessette and R. Zanino, submitted to IEEE Trans. Appl. Supercond. (2011)]

Nuclear fission applications modeling

Development of a computational tool for the full-core coupled neutronic (NE) – Thermal-Hydraulic (TH) analysis of control- and safety-relevant transients in lead-cooled advanced fast reactors [3] [R. Bonifetto, S. Dulla, P. Ravetto, L. Savoldi Richard and R. Zanino, proceedings of 15

th International Conference on

Emerging Nuclear Energy Systems (ICENES), San Fancisco, California, May 15-19, 2011]: - Development of the TH module for a single hexagonal fuel element; - Coupling of the TH and NE modules on a single fuel element.

Fig.1. Cross sections of two applications of the same geometrical model. (a) Superconducting cable of a fusion reactor magnet (grey circles: superconducting strands, black area: cooling He). (b) Hexagonal fuel element of a lead cooled fast fission reactor (orange circles: fuel pins, white area: cooling lead).

(a) (b)


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First name: Silvia LAST NAME: CAMMARANO

Topic: Lighting and energy efficiency

Course year: 1st Tutor(s): Chiara Aghemo, Anna Pellegrino

Academic context [Mardaljevic J., Heschong L., Lee E. 2009. Daylight metrics and energy savings. Lighting Research and Technology, 41 (3), 261-283] [Lee J., Andersen M., Sheng Y., Cutler B. 2009. Goal-based daylighting design using an interactive simulation method. Proc. of the 11

th IBPSA Conference, Glasgow, Scotland, July 27-30, pp. 936-943]

[Reinhart C.F., Mardaljevic J., Rogers Z. 2006. Dynamic daylight performance metrics for sustainable building design. Leukos, 3 (1), 1-25]


Marilyne Andersen: Associate Professor of Sustainable Construction Technologies, Head of the Interdisciplinary Laboratory of Performance-Integrated Design (LIPID), EPFL, Lausanne (CH).


The research program is aimed to assess the applicability of new indicators and simulation tools for a dynamic daylighting design. The CIE Technical Committee TC 3-47 “Climate-based daylight modelling” is presently going to assess and validate the consistency and the applicability of the so-called “Dynamic Daylight Performance Metrics”. Moreover, recently a number of numerical simulation tools was developed and made available, which allowed passing from a static to a dynamic building modelling. The first phase of the research program has been focused on analyzing the characteristics of dynamic daylight metrics through a state of the art of the international ongoing research activity and the characteristics of simulation tools which are currently able to carry out a climate-based modelling. The second phase of the research activity has been focused on: 1. comparing dynamic daylight performance metrics with the conventional daylight factor approach,

analyzing the consistency of new indicators changing the location, the façade orientation, the occupancy pattern and the design illuminance of a simple area, in order to identify limits and potential of both types of approach.

Frequency distributions and cumulative distribution curve for two rooms with different architectural characteristics but similar values of DFm and ALEm and identification of the UDI.

2. showing potentials and limits concerned with each simulation tool in usefully analyzing and representing the results of a lighting analysis from a designer’s point of view and in which stage of the design process its application is more appropriate.

_Pellegrino A., Aghemo C., Lo Verso V.R.M., Cammarano S. 2011. Climate-based metrics for daylighting and impact of building architectural features on daylight availability. Proc. of the 27

th Session of the CIE,

Sun City, South Africa, 10-15 July 2011, pp. 11, Vol. 1, pagine da 82 a 92, ISBN: 9783901906992. _Pellegrino A., Lo Verso V.R.M., Cammarano S. 2011. Limits and potentials of different daylighting design

approaches based on dynamic simulations. Proc. of CISBAT 2011: CleanTech for Sustainable Buildings - From Nano to Urban Scale, EPFL, Lausanne, Switzerland, 14-16 September 2011, pp. 6, pagine da 337 a 342, ISBN: 9782839909068.


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First name: Luigi Consalvo LAST NAME: DE GIORGI

Topic: Thermal fluid dynamic design of a windowless target of an ADS subcritical reactor

Course year: 2011 Tutor(s): Mario De Salve, Bruno Panella

Academic context [Ref 1] Thermal Fluid Dynamics in Nuclear Reactors [Ref 2] Computational Fluid Dynamics [Ref 3] Statistical Modeling for Computer Aided Experiments


Ansaldo Nucleare S.p.A.10)


An algorithm was developed in order to find a suitable geometry for an efficient heat removal in the heat deposition region of a windowless target.

Predicitive models of fluid dynamic quantities of interest have been derived with high degree of accuracy based upon an efficient sampling of the configuration space defined by the algorithm either in 2D-3D approximation of the geometry.

The application of the algorithm permits to reach most of the design objectives imposed.

Alternative solutions of the target geometry, more efficient from the point of view of the design objectives imposed, have been taken into account.

2011 research activities have been presented in UIT congress 2011. Below a list of all my publications related.

1) FLUIDODINAMICA DEL BERSAGLIO WINDOWLESS NEI PROGETTI TIPO XADS ED EFIT. XXVII Congresso UIT sulla Trasmissione del Calore. Reggio Emilia, Giugno 2009

2) EXPERIMENTS ON THE ADS INNOVATIVE NUCLEAR REACTOR TARGET AT POLITECNICO DI TORINO. ASME-ATI-UIT 2010 Conference on Thermal and Environmental Issues in Energy Systems-Sorrento 16-19 May 2010

3) THERMAL HYDRAULICS IN THE ADS WINDOWLESS TARGET EQUIPPED WITH INTERNAL GUIDE VANES. XXIX Congresso UIT sulla Trasmissione del Calore. Torino 20-22 Giugno 2011

Fig. Temperature field in the median section of the windowless target and related half-geometry


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First name: Baptiste LAST NAME: DELHOMME

Topic: Thermal integration of a metal hydride tank and a Solid Oxide Fuel Cell (SOFC)

Course year: 4th Tutor(s): P. De Rango (CNRS - Institut Néel - CRETA), M. Santarelli (Politecnico di Torino)

Academic context [ref 1] De Rango, P., Chaise, a, Charbonnier, J., Fruchart, D., Jehan, M., Marty, P., Miraglia, S., et al., Nanostructured magnesium hydride for pilot tank development, Journal of Alloys and Compounds, 2007, 446-447. [ref 2] Chaise, a., de Rango, P., Marty, P., & Fruchart, D., Experimental and numerical study of a magnesium hydride tank, International Journal of Hydrogen Energy, 2010, 35(12), 6311-6322. [ref 3] Pfeifer, P., Wall, C., Jensen, O., Hahn, H., & Fichtner, M., Thermal coupling of a high temperature PEM fuel cell with a complex hydride tank, International Journal of Hydrogen Energy, 2009, 34(8), 3457-3466.


CNRS - Institut Néel - CRETA, Grenoble, France

CNRS - LEGI, Grenoble, France

CNRS - ICMPE, Thiais, France

McPhy Energy, La Motte Fanjas, France

Highlights of the research activity So far the possibility to feed Solid Oxide Fuel Cells (SOFC) with pure hydrogen was scarcely studied. Indeed, the possibility to feed the SOFC with low cost fuels other than natural gas or coal syngas is one its main advantage. If low cost hydrogen produced from renewable energies (wind turbine, solar panels) will become available over the next decades, a fuel cell system based fed by hydrogen could allow to solve the issue of intermittency production from renewable energies. SOFC H2-fed systems could be of particular interest for off-grid sites, for fitting the power consumed on the grid or as UPS (Uninterruptible Power Supplies) featuring a high energy density. In addition, the possibility of a regenerative fuel cell system in aerospace applications could be another interesting application. When H2 fuel is used, an efficient and safe mean for hydrogen storage is needed. Currently, the most developed storage solutions at industrial scale are either compression at very high pressure (200 - 350 bar) or liquefaction at cryogenic temperature (20 K) and subsequent compression. Otherwise, in a magnesium hydride tank, absorption at 10 bars and 360 °C allows one to reach the same volumetric density as for liquid hydrogen. The energy cost for hydrogen storage is ~20% of LHV (Low Heating Value) with gas-phase compression, ~30% with cryogenic liquefaction and again ~30 % to store it as magnesium hydride. Thermal integration of a hydride tank with an SOFC system should allow to recover the energy needed for hydrogen desorption from the stack outlet gases flowing at high temperature (800 °C). For the first time a 1kW SOFC stack and a high temperature hydride tank were integrated and tested.


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First name: Enrico................................... LAST NAME: DELOGU................

Topic: Innovative CFD methodologies for Spark Ignition Engines.........................................

Course year: 2nd..... Tutor(s): Prof. F. Millo..........................

Academic context [ref 1] Badami, Bevilacqua, Millo, Chiodi, Bargende, “GDI Swirl Injector Spray Simulation: A combined Phenomenological-CFD Approach”, SAE Paper 2004-01-3005, 2004 [ref 2] Scarcelli, Wallner, Matthias, Salazar, Kaiser, “Mixture Formation in Direct Injection Hydrogen Engines: CFD and Optical Analysis of Single- and Multi-Hole Nozzles”, SAE Paper 2011-24-0096, 2011


Continental Automotive

FEV GmbH

Highlights of the research activity In the last decade, constantly reduced pollutants and CO2 limits have driven the design activity of new engines. Diesel engines, traditionally convenient in terms of fuel consumption, are nowadays challenged from spark ignited engines, which allow lower pollutant emissions and an easier and cheaper after treatment system. A series of key technologies and concepts, such as downsizing and downspeeding, direct injection, turbocharging and variable valve actuation, are nowadays applied to the modern spark ignition engines in order to increase the efficiency and make them competitive against diesel engines also in terms of fuel consumption and “fun to drive”.

The degrees of freedom available adopting these technologies – such as the definition of the injector targeting and injection strategy, the valve timing, the effect of the boost pressure on performance and knock behavior, in conjunction with reduced time to market and development cost – make 3D-CFD simulations play a more relevant role, especially in the first phase of the design process, using them as a virtual test-bench where different concepts can be analyzed in a time and cost effective way.

The predictive capability of CFD simulation is strongly affected by the quality of the sub-models adopted. Many phenomena affecting the charge formation process, such as the spray behavior under flash-boiling conditions, the interaction of the droplets with the walls, the multi-component composition of the gasoline, still require a considerable effort for defining an appropriate model to simulate them. Furthermore, the large quantity of data obtained from a CFD tool has to be properly organized and interpreted in order to obtain clear and streamlined information capable to drive the design process and the concept evaluation.

This research work has been focused in its first part on the study and implementation of suitable models for the simulation of the injection process in Spark Ignition Engines. The activity has been carried out partly using a previous research work performed in the same research group, and partly thanks to collaboration with Continental Automotive in Regensburg (Germany), one of the major injection system suppliers. In the second phase, that is still on-going, the work has been focused on the evaluation of the charge motion and in-cylinder injection process, comparing CFD investigation with experimental optic measurements, thanks to the facilities available at FEV GmbH in Aachen (Germany).

In addiction to the model implementation and evaluation, a series of post-processing tools has been developed, tested and used on many different engines, thanks to the on-going collaborations with many OEMs and supplier.

CFD simulation of the

injection process in a

DISI engine


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First name: Antonio Fabio LAST NAME: DI RIENZO

Topic: Mesoscopic numerical methods for reactive flows: lattice Boltzmann method and beyond

Course year: 3rd Tutor(s): Pietro Asinari, Eliodoro Chiavazzo

Academic context [ref 1] Y. Qian, D. d’Humieres, P. Lallemand, Lattice BGK models for Navier-Stokes equation, EuroPhys. Lett., 1992, 17, 479-484 [ref 2] C. E. Frouzakis, Lattice Boltzmann Methods for Reactive and Other Flows, Fluid Mechanics and Its Applications, 2011, Vol. 95, Part 4, 461-486 [ref 3] N. I. Prasianakis, I. V. Karlin, Lattice Boltzmann for simulation of compressible flows on standard lattices, Phys. Rev. E, 2008, 78, 016704-016710


Paul Scherrer Institute (PSI)

Highlights of the research activity 1) Lattice Boltzmann method for reactive flows A lattice Boltzmann (LB) scheme for simulating reactive flows at the low Mach number limit has been developed, on the basis of a recently proposed compressible thermal model (Prasianakis N.I., Karlin, I.V, PRE, 2008). Combustion problems exhibit significant density changes due to the heat release in chemical reactions. Therefore, consistent LB schemes are requested to behave macroscopically like a compressible solvers. So far, no models for simulating reactive flows have been developed so as to account for large density and temperature variations. Reason for this is that they are all based on incompressible LB method, where density is nearly constant. The proposed scheme actually overcomes this lack. A new scheme for solving the mass conservation equation for each chemical species has also been developed, in order to account for compressibility effects: this is achieved by modifying both the equilibrium distribution function and the relaxation frequency in the kinetic equation. The proposed scheme has been validated against FLUENT (see Fig. 1) in case of hydrogen/air reactive mixture: solutions of are found to be in good agreement with the reference results. 2) Link-wise Artificial Compressibility Method (LW-ACM) Due to its pseudo-kinetic origin, LB methods work with an enlarged set of unknowns, including the ghost variables, beyond the fluid-dynamics variables. LW-ACM overcomes this limitation: the updating of the distribution function is ruled only by the hydrodynamic quantities. Moreover, LW-ACM is compatible with all LBM existing technologies (grid refinement, interpolation-based boundary conditions, …) and preserves its meshless approach. An equivalent scheme can be also formulated in terms of conventional numerical methods (finite differences, finite volumes), so that LW-ACM can take advantage of solutions from either LBM or traditional CFD.

Fig. 1 Density, velocity,

temperature and species mass

fractions across the mid-plane.

Solid line and symbols

represent the LB and FLUENT

solutions, respectively.

http://www.springerlink.com/content/0926-5112/

http://www.springerlink.com/content/0926-5112/


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First name: Phani Kumar LAST NAME: DOMALAPALLY

Topic: CFD Analysis of flow boiling in the ITER first wall

Course year: 2nd Tutor(s): R. Zanino, F. Subba, L. Savoldi Richard

Academic context [ref 1] W.M. Rohsenow , A Method of Correlation Heat Transfer Data for Surface Boiling of Liquid,

Transactions of ASME 74 (1952) 969-976.

[ref 2] A.E. Bergles and W.M. Rohsenow, The determination of Forced convection surface boiling heat

transfer, Journal of Heat Transfer 86 (1964) 365-372.

[ref 3] D.L. Youchison et al., Prediction of Critical Heat Flux in Water-Cooled Plasma Facing Components

using Computational Fluid Dynamics, Fusion Science and Technology 60 (2011) 177-184.


Highlights of the research activity The research activity was mainly concentrated on CFD analysis of flow boiling inside international

thermonuclear experimental reactor (ITER) first wall (FW). During the operation of ITER the heat loads can

be as high as several MW/m2 , which should be removed through a proper cooling system. The proposed

sink to handle this load consists of copper alloy (CuCrZr) hypervapotron or swirl tubes, which exploit the

large heat transfer coefficient (HTC) characteristic of highly sub-cooled boiling. In order to predict the

performance of the system in advance a proper CtFD tool is required, so two such tools were tested and

compared on two different models. First, Rohsenow model [1] as in STAR-CCM+, which is having the

capability of transition from nucleate boiling to film boiling and second, Bergles and Rohsenow model [2] as a

user defined function (UDF) in FLUENT. This is the first time that Rohsenow and BR models were critically

compared for an ITER-relevant application. The models were tested on Flat-channel geometry and the

results were compared against the experimental results obtained from Efremov institute Russia and then

some preliminary tests were conducted on hypervapotron geometry.

Publications : Phani Domalapally et.al., “CFD Analysis of flow boiling in the ITER first wall”, submitted to

FED.

Comparison of temperatures computed with the

Rohsenow (solid line) and the BR (dash-dot line)

models on Flat channel, with the thermocouple data

(symbols) for Vin = 1 m/s and at different heat fluxes.


15 | P a g e

First name: Mauro Giovanni LAST NAME: FERRERO

Topic: Theoretical and experimental assessment of small-scale trigeneration systems

Course year: 3rd year Tutor: Prof. Marco Badami

Academic context [ref 1] Badami M, Portoraro A, Ruscica G. Analysis of trigeneration plants: engine with liquid desiccant

cooling and micro gas turbine with absorption chiller. Int J Energy Res, doi:10.1002/er.1817; [ref 2] Camporeale SM, Fortunato B, Mastrovito M. A modular code for real time dynamic simulation of gas

turbines in Simulink. ASME J Eng Gas Turbines Power 2006;128(3):506-17; [ref 3] Vidal A, Bruno JC, Best R, Coronas A. Performance characteristics and modelling of a micro gas

turbine for their integration with thermally activated cooling technologies. Int J Energy Res 2006;31(2):119-34.


Universitat Rovira i Virgili - Tarragona (Spain)

Highlights of the research activity The research activity is focused on the assessment and modeling of micro-trigenerative systems with specific reference to: - theoretical and experimental analysis and modeling of micro gas turbine systems; - experimental analysis of thermally activated technologies; - energetic and economic optimization of electrical, thermal and cooling production operations. In particular, a trigeneration system installed at the Politecnico di Torino has been experimentally characterized at different ambient and load conditions. The prime mover is a micro gas turbine, that can be coupled to a LiBr absorption chiller or to a desiccant cooling system. Moreover, a dynamic simulation tool in a Matlab Simulink environment of the micro turbine and the absorption chiller has been developed. The model implements the mass, energy and momentum equations of the main components of the power plant, i.e. compressor, regenerator, combustion chamber, turbine and heat exchangers. A double control system has also been set up, with the aim of maintaining the rotational speed of the turbine /compressor assembly at the nominal fixed value, and at limiting the Exhaust Gas Temperature (EGT) below the limit value. The model has been validated by means of the collected experimental data. The aim of this work was to set up a dynamic model which, with a few technical data as input, could well describe the performances of the plant, both at rated and at part load conditions, taking into account the most important transient phenomena. This particular feature, innovative in the literature, allows the performance of plants in the small-scale range (30-300 kW) to be simulated with a good accuracy, by only feeding the model with the main data obtainable from datasheets. The results can be used for the optimization of the operation, maintenance and management strategies of the energetic production in a multi-generation system.

Scheme of the trigeneration power plant: mGT and Absorber

exhaust gases

Flue gas /

water HX

Power

electronic

unit

fuel

compressor

PQ

T,p,VF 2

T 3

CC

TC

T 4

R

E

G

E

N

GEN

Pel

to stack

GA T 5

T,p,RH 0

T 1

Hot water

collector

Cold water

collector

T7

pump

fan

Cooling

tower

cooling air

main cold

water piping

MF, T 11

pump

T8

MF,T 9

GEN

ABS

COND

EVA

T10

pump

pump

MF,T 13

T12

MF,T 6


16 | P a g e

First name: ................ABDUL.................. LAST NAME: ............GHAFOOR….

Topic: Solar Assisted DHW and Air-Conditioning: Theoretical Simulations and Field Data

Course year: …2nd ..... Tutor(s): G.V FRACASTORO......

Academic context 1. Fong, K.F., C.K. Lee, T.T. Chow, Z. Lin, L.S. Chan. 2010. Solar hybrid air-conditioning system for high temperature cooling in subtropical city. Renewable Energy 35 (2010) 2439-2451 2. Riahi, A., H. Taherian. 2011. Experimental investigation on the performance of thermosyphon solar water heater in the south caspian sea. Thermal Science 15 (2011) 447-456. 3. Agyenim, F., I. Knight, M. Rhodes. 2010. Design and experimental testing of the performance of an outdoor LiBr/H2O solar thermal absorption cooling system with a cold store. Solar Energy 84 (2010) 735–744


PROVINCIA DI TORINO

ECOJOULE & FRIGORIFERI BAVA

IPLA

Highlights of the research activity Solar collectors for DHW:

The goal of this work is to describe a methodology adopted for the experimental efficiency evaluation of solar collector systems for domestic hot water production (SCDHW).

In situ measurements of SCDHW system performance, including storage and back-up heating, have been compared with results from simulations performed using scientific (TRNSYS), widely spread (POLYSUN) software and F-Chart method.

In this study ten SCDHW systems were analyzed in the Province of Turin. In situ measurements were carried out for at least 20 days for each plant, with sampling rate of ten minutes using ultra sound flow meter, temperature probes and data logger for pump status.

According to the common experience, an estimate of 1m

2 of collector is

recommended for 40L/day hot water demand for northern Italy. Simulations showed that the optimum size is 1 m

2

per 25-33 L/day.

Results also show that generally the solar Collector’s area was exceeding actual DHW needs, resulting in measured lower efficiency (around 30%) than calculated by software as shown in Figure.

Solar assisted Air-Conditioning:

The solar cooling installation at IPLA is simulated using PolySun and comparison is made with measured data at the Installation.

The purpose of this study is to simulate and optimize the installation components for best possible efficiency and COP of the system. The system is simulated using different types of collectors and different hot water inlet temperatures to adsorption chiller by varying control of auxiliary system for production of chilled water at 9-16

oC.

A POLITO-BAVA solar cooling laboratory will be established on the roof of DENER and measured data will be used to optimize the design of a prototype small size kit for solar air-conditioning of residential buildings.

Model-A&B=Measured data; PolySun-A & F-chart-A= 1m2/(40L/Day);

PolySun-B & F-chart-B= 1m2/(25-33L/Day)

Useful Energy Produced

0

100

200

300

400

500

600

700

800

900

1 2 3 4 5 6 7 8 9 10Case Studies

kW

h/m

2

Model A Model B PolySun A F-chart A PolySun B F-chart B


17 | P a g e

First name: Marco LAST NAME: GIANOGLIO BERNARDI

Topic: In Cylinder NOx reduction technologies for marine Diesel engines

Course year: 3rd Tutor(s): Federico Millo

Academic context [ref 1] ISAKSSON, S., “The Miller Cycle and its Application on a Medium Speed Diesel Engine”, Master Thesis, Helsinki University of Technology, 2000. [ref 2] CODAN, E., BERNASCONI, S., BORN, H., “IMO III Emission Regulation: Impact on the Turbocharging System”, Paper 139, CIMAC, Bergen, 2010. [ref 3] EDWARDS, S. P., FRANKLE, G. R., WIRBELEIT, F., RAAB, A.: “The Potential of a Combined Miller Cycle and Internal EGR Engine for Future Heavy Duty Truck Applications”, SAE Paper 980180, 1998.


Wärtsilä

Highlights of the research activity Different external EGR strategies, combined with extreme Miller cycles, were analyzed by means of a 1D-CFD simulation code for a marine diesel engine, to evaluate their potential in order to reach the IMO Tier 3 NOx emissions target. By means of extreme Miller cycles, with Early Intake Valve Closures (up to 100 crank angle degrees before BDC), a shorter compression stroke and lower charge temperatures inside the cylinder can be achieved and thanks to the cooler combustion process, the NOx specific emissions can be effectively reduced. However, the remarkably high boost pressure levels needed for such extreme Miller cycles, require mandatorily the use of two stage turbocharging systems. Despite two stages turbocharging, combined with extreme Miller timings, may allow up to 50 % NOx reduction compared to a conventional, single stage turbocharger architecture, further NOx emissions reductions are necessary to meet the IMO Tier 3 NOx limit. Higher EGR percentages, which could be achieved by means of external circuits, were therefore also evaluated. However, it should be pointed out that, although the external EGR technology is well established for automotive and heavy duty diesel engines, it is not yet state of the art for marine diesel engines, and its application to a highly boosted engine using extreme Miller timings is not straightforward. Several different complex EGR routes were thus investigated, and for the preliminary assessment of their NOx emissions abatement potentialities, the use of numerical simulation allowed a detailed and extensive evaluation of the effects on engine performance, fuel consumption, NOx emissions and thermal and mechanical loads on engine components of the combination of different intake valve profiles, intake valve closure timings and scavenging periods with different external exhaust gas recirculation solutions. Percentages of exhaust gases recirculated in the combustion chamber up to 20% were evaluated that combined with extreme Miller timings (up to 100 crank angle degrees before BDC) allowed up to 90 % NOx reduction compared to a conventional, single stage turbocharger architecture, with only moderate BSFC increase.

Engine layout with two stage turbocharging system and external EGR

system


18 | P a g e

The vision of the dynamic and active building envelope system and its functioning mechanisms

First name: Francesco LAST NAME: GOIA

Topic: Responsive Building Envelope Components and net Zero Energy Buildings

Course year: 2nd Tutor(s): Marco Perino (PoliTo), Matthias Haase (NTNU)

Academic context [ref 1] IEA – ECBCS Annex 44, Integrating Environmentally Responsive Elements in Buildings, Design Guide

– Vol. II, 2010. [ref 2] Manz H., Egolf P.W., Suter P., Goetzberger A., 1997. TIM–PCM external wall system for solar space

heating and daylighting. Solar Energy 61(6), 369-379. [ref 3] Zeng R., Wang X., Di H., Jiang F., Zhang Y., 2011. New concepts and approach for developing

energy efficient buildings: Ideal specific heat for building internal thermal mass. Energy and Buildings 43(5) 1081-1090


Norwegian University of Science and Technology – The Research Centre on Zero Emission Buildings

ENEA – Unità Tecnica per L’Efficienza Energetica

Università degli Studi del Piemonte Orientale “Amedeo Avogadro” – Dipartimento di Scienze e Tecnologie Avanzate

Highlights of the research activity The research activity deals with the identification, development, and assessment of possible configurations of dynamic building skins, with the aim of conceiving integrated building envelope solutions for highly energy-efficient buildings. The research activity is organized in three different levels: 1) concept/theory level, 2) system level and 3) material/technology level. 1) In 2011, a numerical model has been developed to establish a hierarchy among the different functions that

a dynamic building skin may perform, and to understand the suitable range of dynamicity of each property. Simulations will be performed in early 2012.

2) The experimental and numerical analysis of the energy performance of a multifunctional façade module is ongoing. In 2011 a prototype of the façade module has been assembled on a test cell facility and the main physical quantities are currently continuously recorded. The comparison between experimental data and numerical simulations performed in 2011 will be carried out to validate the numerical model. A detailed analysis on the energy performance of the façade module is expected in late 2012.

3) A physical-mathematical model of PCM glazing systems has been developed in 2011, and data from simulations compared with experimental measurements. The model is able to replicate, with some limitations, the thermo-physical behaviour of the system, and may represent a good starting point for a further improvement of the numerical tool. The numerical model will be used to develop new configurations of PCM glazing systems and to evaluate their performance in different climates. A full characterization of the optical properties of a PCM layer has also been carried out in 2011, and data obtained during this activity will be used in the above mentioned model. Finally, a detailed chemical-physical analysis of a PCM, aged by exposure to solar energy, was performed. In particular, the thermal stability, the evolution of the thermo-physical properties and of the PCM’s structure were investigated.


19 | P a g e

First name: .....Cosimo............................. LAST NAME: GUERRA.......................

Topic: Experimental analysis of SOFCs fed by non-conventional fuels.

Course year: 2nd Tutor(s): M. Santarelli, P. Asinari

Academic context -Lanzini A, Leone P. Experimental investigation of direct internal reforming of biogas in solid oxide fuel cells, International Journal of Hydrogen Energy 2010;35(6):2463-76. -Sumi H, Lee Y, Muroyama H, Matsui T, Eguchi K. Comparison Between Internal Steam and CO2 Reforming of Methane for Ni-YSZ and Ni-ScSZ SOFC Anodes Journal of The Electrochemical Society 2010;157(8):B1118-B1125. -Koh J, Yoo Y, Park J, Lim H. Carbon deposition and cell performance of Ni-YSZ anode support SOFC with methane fuel, Solid State Ionic 2002;149:158-166


Centro ricerche e sviluppo, Edison S.p.a., Trofarello (To)

Imperial College, London

Highlights of the research activity The main part of the work investigates the degradation mechanisms of a Ni-based anode supported solid oxide fuel cell under direct internal dry reforming of CH4 at 800°C. Several experiments have been performed including long-term ageing tests (up to 300h) under dry reforming reaction with different stoichiometry. The degradation of the SOFC cells is analyzed by observing the voltage decay under galvanostatic mode (15 Ampere at FU=60%) and by taking impedance spectra after each 50h of operation. Moreover, post-mortem analysis is performed after each experiment by using electron scanning microscope (SEM). In the picture below, the behavior of the SOFC under different CH4/CO2 ratios (r1=1/1;r2=1/2;r3=1:3) is compared. As expected, SEM confirmed that carbon deposition is conspicuous for stoichiometric direct dry reforming reaction leading to the formation of wiskers-like carbon, which is less and less evident for higher content of CO2. Experiments show a very similar trend of the curves, with an evident degradation of performances in all the CH4/CO2 ratios examined after about 200 hours. Hence, deposited solid carbon, which leads to the degradation of the anode performance due to deactivation of nickel catalyst, is not the only degradation mechanism. These results, combined with EIS measurements, could suggest that high fuel utilization (FU) plays the main role in the worsening of the long term behavior of the SOFC. In this conditions, the harmful effect of the mass transport resistances is arising with the time. The high concentration of the reaction products (obstructing or blocking potential reaction sites) and the low partial pressure of fuel play an adverse role for the flux of the reactants and their diffusion through the porous interstices of the anode, increasing the concentration polarization. Moreover, re-oxidation of Ni, caused by the shortage of fuel in the catalytic sites, increases ohmic resistances.

http://www.scopus.com.ezproxy.biblio.polito.it/source/sourceInfo.url?sourceId=26991&origin=recordpage


20 | P a g e

First Name: AKSHAT Last Name: KHOLIA

Topic: Thermal Hydraulic Analysis of AC losses in the KSTAR PF1 coil

Course year: 2nd

year (2010-2011) Tutor(s): L. Savoldi Richard, R. Zanino

Academic context [1] Lee HJ, et al. The AC loss measurement of the KSTAR PF1 coils during the first commissioning, IEEE Trans. Appl. Supercond. 2010; 20: 551-5. [2] Savoldi Richard L, Casella F, Fiori B, and Zanino R. The 4C code for the cryogenic circuit conductor and coil modeling in ITER, Cryogenics 2010; 50:167-76. [3] M.N. Wilson. NbTi superconductors with low ac loss: A review, Cryogenics 2008; 48: 381-395.


National Fusion Research Institute, Korea.


The KSTAR tokamak, in operation since 2008 at the National Fusion Research Institute in Korea, is equipped with fully superconducting magnet system. The Central solenoid of the magnet system comprise of 4 symmetric pairs of coils PF1L/U-PF4L/U [1]. Each of the CS is a double pancake wound using the Nb3Sn CICC with square Incoloy jacket. The coils are cooled with supercritical He in forced circulation at normal 4.5 K and 5.5 bar in inlet conditions.

Since CS coils are subjected to the rapidly varying currents during the operation, AC losses are prevalent in them. Moreover, it was found during experimental campaigns that the temperature increase at the outlet was higher than expectation. Keeping this anomaly in mind, during this year’s activity 4C code was applied to PF1 coil to analyze the AC losses. Using 4C, one can do the thermal hydraulic analysis of the coil system as a whole, including the coupled cryogenic circuit(also see figure 1) which provides the necessary boundary conditions [2].

In the first phase of activity this year, the 4C was applied for the trapezoidal pulse with plateau current of 10kA with ramp up and ramp down rates of 1 kA/s and 10kA/s respectively. The exercise gave an indication of distribution of losses over the coil, although the losses were underestimated. Also, can be found in literature [3] that there isn’t a single coupling time constant (nτ) for the multi-staged cable in conduit conductors and depends on cabling stages & current distributions attributed to different cabling stages. So, during the second phase, analysis for AC losses was done for a set of ramp rates with same plateau current (i.e. 15kA) and single coupling time constant (nτ) was found in such a way to best fit the temperature at the outlet and inlet. The study also confirmed that the coupling time constant decreases with the increasing ramp rates dB/dt including the ramp in the first phase.

Figure 1. represents a schematic of 4C including the

circuit components (in blue), the coil (in yellow) and

windings in the coil (in red).


21 | P a g e

First name: Sabino Paolo LAST NAME: LUISI

Topic: Effects of Different Configurations of the Combustion Chamber on the Performance of a VVA Gasoline Engine

Course year: 2010 Tutor(s): Federico Millo

Academic context [ref 1] Rudolf Flierl, Daniel Gallasch, Andreas Knecht, Wilhelm Hannibal: “Improvements to a four Cylinder Gasoline Engine Throught the fully Variable Valve Lift anf Timing System Univalve”, SAE 2006-01-0223.

[ref 2] Rinolfi, R.; Piccone, A.: The potential of an advanced electronic valve control system for future spark ignition engine. 6th Aachen Colloquium, Automobile and Engine Technology, October 2022, 1997, Aachen.

[ref 3] Wolfram Wiese, Stefan Pischinger Adomeit and Jens Ewald: Prediction of Combustion Delay and Duration of Homogeneous Charge Gasoline Engines based on In-Cylinder Flow Simulation - SAE 2009-01-1796


CRF (Fiat Research Center)

Highlights of the research activity The PhD activity of the first year has been focused on the experimental investigation of three different combustion chambers and their effects on burning velocities. The analysis was performed on a turbocharged 1.4 liter VVA (Variable Valve Actuation) [1], [2] gasoline engine with 4 in-line cylinders and 16 valves. The innovative layout of the induction system allows to introduce EGR (Exhaust Gas Recirculation) and also modulate the engine displacement using two or three cylinders so as to maximize the fuel conversion efficiency. This particular flexibility is exclusive of MultiAir system, patented by FIAT, and represents a new challenge in the emission reduction of gasoline engines. The first step of the research activity was a characterization of the baseline cylinder head in partial and full load conditions; subsequently, two different concepts have been developed and analyzed: the first one is the enhancement of turbulence by increasing the tumble motion (V1 in the reported figure), while the second is based on the addition of a mild swirl vortex to the fuel-air mixture (V2 in the reported figure). At partial loads the investigation of the three configurations has been focused on the tradeoff between fuel consumption and combustion stability with highly diluted mixtures, since the introduction of EGR (Exhaust Gas Recirculation), in gasoline engines, allows to reduce pumping losses and indeed fuel consumption. The experimental analysis involved also the study of the combustion features through the acquisition of the four in-cylinder pressure signals. At part load the concept of increasing tumble motion is the most effective in enhancing the burning velocities, and experimental data show that the main effect is the reduction of the first phase of combustion, that involves the 5% of burnt mass. However, the performance in full load conditions is not adequate to the baseline levels, because the overall tumble motion is decreased at the highest valve lift. The cylinder head with the addition of a mild swirl motion to the tumble vortex gave intermediate advantages between the baseline and the high tumble solution in terms of fuel consumption; at full rated power it was possible to reach the performance of the reference configuration.

In cylinder pressure at 2500 rpm in full load conditions, (mean over 200 engine cycles and the

four cylinders). The Spark Advance used is at Detonation Limit for each configuration.

Pre

ssu

re [

bar]

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10

20

30

40

50

60

70

Volume/Volume Ref [-]

0.0 0.2 0.4 0.6 0.8 1.0 1.2

2500 rpm BASE V1 V2


22 | P a g e

First name: GRAZIA LAST NAME: MONNI

Topic: Special Instrumentation for two phase flow

Course year: 1st Tutor(s): Prof. B. Panella, Prof M. De Salve

Academic context Nuclear Thermal-Hydraulics Two-phase Flow Measurement and Instrumentation


CIRTEN

SIET Piacenza

ETH Zurich

Highlights of the research activity In the frame of the LP2 program “Reattori evolutivi INTD”, focused on small and medium nuclear reactors, the thesis consists on the development of special instrumentation and on the development of models, based on experimental analysis, that are be able to interpret the measurement signals under many possible two-phase conditions, with particular reference to the thermal-hydraulics of nuclear reactors in steady state and transient conditions. In the first work the horizontal air-water flow has been investigated by means of a Spool Piece (SP), that consists of two instrumentation devices connected in series, that is a Turbine Flow Meter and a Drag Disk. From the experimental data, an operating map of the SP has been derived; the analysis and the processing of the electric signals of the SP, allows to characterize the flow in terms of flow pattern and mass flow rates of the two phases with an accuracy of 15%. In the first year I also started the research activities on the development and the analysis of instruments based on the impedance technique in order to measure local and average parameters of the two-phase mixture such as the void fraction, and the phases distribution in horizontal and vertical pipe flow. In particular the following instrumentation devices are being investigated: concave probes in order to analyze the horizontal flow and the behavior of the instruments inserted in a SP; Wire Mesh Sensor: Analysis of horizontal air/water flow (chordal and sectional void fraction, interface evolution) ECT (Electrical Capacitance Tomography), in collaboration with SIET, in order to develop and analyze of the sensor in the vertical annular and mist air/water flow.


23 | P a g e

First name: Edoardo Pietro.............................. LAST NAME: MORRA................................

Topic: Optimization of hybrid electric vehicles…………………..............................................

Course year: 3rd year......... Tutor(s): E. Spessa, A. Vassallo......

Academic context M. Montazeri-Gh, A. Poursamad, B. Ghalichi, Application of genetic algorithm for optimization of control strategy in parallel hybrid electric vehicles, Journal of The Franklin Institute 343 (2006), 420-435

Seibel, J., “Optimierte Auslegung von Ottomotoren in Hybrid-Antriebsträngen”, Dissertation, Institute for Combustion Engines, RWTH Aachen University, 2008

Daniel Ambuhl, “Energy management strategies for hybrid electric vehicles”, Dissertation, ETH Zurich, 2009


GMPT-E (Torino)

RWTH and FEV (Aachen) AVL (Graz)

Highlights of the research activity Stage at RWTH: simulation study for the minimization of the well-to-wheel CO2 emissions of a city car through electrification. A Series Hybrid Electric Vehicle, a mixed hybrid electric vehicle and a battery electric vehicle were compared to a conventional one. For the optimization of each powertrain an innovative combination of Design of Experiment, driving cycle simulation and numerical optimization was employed. The optimization criterion is the well-to-wheel CO2 emissions with respect to the burned fuel and the electric energy used from the network

Activity at Polito: a zero-dimensional model in Matlab environment was implemented to simulate the considered hybrid powertrain. A statistical approach based on Genetic Algorithm techniques is adopted to identify the optimal operating strategy for a series hybrid electric vehicle, a parallel hybrid electric vehicle and a mixed hybrid electric vehicle with both a diesel and a gasoline internal combustion engine. First, a novel benchmark optimization is obtained giving the electric machine the highest number of degrees of freedom: every time step the electric machine can assume an independent power level. Afterwards, two different real-time optimizers, based on the reduction of total losses and on the total load-switch thresholds have been implemented. The results show the effectiveness of the method and the achieved improvements in terms of fuel consumptions and NOx emissions.

EM 1InverterBattery

ICE

EMInverter

Battery

ICE

Gearbox

EM 2

EM 1InverterBattery

ICEEM 2

SERIES HYBRID ELECTRIC VEHICLES

PARALLEL HYBRID ELECTRIC VEHICLES

MIXED HYBRID ELECTRIC VEHICLES


24 | P a g e

First name: ... Gustavo Adolfo............... LAST NAME:ORTIGOZA VILLALBA...

Topic: .Design, development and testing of planar solid oxide fuel cell (SOFC) stack.

Course year: . 3rd.... Tutor(s): .... Prof. Massimo SANTARELLI..

Academic context [ref 1] Alternative Power Sourcing [ref 2] High Temperature Materials [ref 3] Electrical Engineering


EDISON SPA

CNRS (French National Center for Scientific Research)

TOPSOE

Highlights of the research activity The aim of the research is the design, in-house production and experimental analysis of a planar geometry SOFC stack. The research activities have been subdivided as follows:

DESIGN OF PLANAR ANODE-SUPPORTED SOFC STACK:

Fluid dynamic design of reactant distribution system for both sides of the cell (anode and

cathode).

Electrical and Mechanical design to guarantee a high performance with focus on:

a) electrical cell interconnection; b) mechanical improvement, c) sealant materials position

DEVELOPMENT OF PLANAR ANODE-SUPPORTED SOFC STACK:

Electrical and mechanical behavior analysis of materials (ceramics, metallic and cermets)

used at high temperatures.

Development and production of NiO-YSZ nanostructured planar anodes by means of an

innovative process “Pressure Assisted Field Electrical Sintering” (PAFES).

Testing and characterization of nanostructured planar anodes.

Testing of sealant materials.

Production and testing of a small stack with different alternative fuels to natural gas.

Characterization of the planar SOFC stack.

Mono Cell Stack configuration

Efficiency with different H2 flow rates

http://www.google.it/url?sa=t&rct=j&q=%E2%80%A2%09cnrs%20(research%20center%20of%20france&source=web&cd=2&sqi=2&ved=0CCwQFjAB&url=http%3A%2F%2Fwww.cnrs.fr%2Fen%2FaboutCNRS%2Foverview.htm&ei=VYbnTojnAdGM-wa-wcnICg&usg=AFQjCNF5dhuVwap4frczRAHie8uRibKThg


25 | P a g e

Fig. Pilot plant dry anaerobic digester at FEM and SOFCs Test

station at DENER

First name: .....Davide................................... LAST NAME: .......PAPURELLO.......

Topic: Biogas trace characterization for innovative SOFC feeding and bio-methane utilization

Course year: ....1..... Tutor(s): ......Santarelli Massimo.......

Academic context [ref 1] poster submitted for the 10

th SOFC forum, 26-29 June 2012, KKL – Lucerne - Switzerland

[ref 2] poster submitted for EU BC&E 2012: Biogas, 18-21 June 2012, Biowaste, Bioenergy in Smart Grids – Milano Convention Centre - MiCo [ref 3] article under submission for Waste Management journal, Elsevier, Monitoring of VOCs formation in a dry anaerobic pilot plant using PTR-ToF-MS


Edmund Mach Foundation (FEM – San Michele a/A (TN), via E.Mach 1 – 38010)

SOFCpower spa (Mezzolombardo (TN), Viale Trento, 115/117, c/o BIC – I – 38017)

Highlights of the research activity I started my research from the work done during my master thesis, where I begun to study the commercial SOFCs feeding by biogenous fuel, as biogas coming from anaerobic digestion and syngas coming from gasification of wood. It was studied the electro-catalytic and transport properties using an Electrochemical characterization coupled with carbon deposition limitation investigation using three different reforming agents. In this year, thanks to the collaboration with FEM and SOFCpower, I started my research with a detailed trace analysis of the biogas produced from an innovative dry digestion pilot plant that exploits OFMSW. Investigation Tests are made at FEM using a PTR-QMS and PTR-TOFMS, two different analytical instrument able to perform a proton transfer reaction of the volatile compounds and quantify it through a Quadrupole and Time of Flight Mass Spectrometer. In this way we characterized biogas functions of a specific organic substrate in terms of trace compounds, moreover we studied the kinetic mechanisms of these compounds along the production. We detected several VOCs that could be dangerous for the SOFC generator, even at low ppm values as hydrogen sulfide, mercaptans, tars…For this reason I started to design and to test in laboratory a reactor system, using activated commercial carbons with Iron and Copper, to adsorb sulfur compounds.


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First name: Nicola LAST NAME: RAPETTO

Topic: Modeling of Innovative Injection Systems for Turbocharged DI CNG Engines and Spray Simulation

Course year: 2nd Tutor(s): Andrea E. Catania, Ezio Spessa

Academic context [1] Korakianitis, T., Namasivayam, A.M., and Crookes, R.J., “Natural-gas fueled spark-ignition (SI) and compression-ignition (CI) engine performance and emissions”, Progress in Energy and Combustion Science, Vol. 37, pp. 89-112, 2011. [2] Baratta, M., Catania, A.E., and Pesce, F.C., “Multidimensional Modeling of Natural Gas Jet and Mixture Formation in DI SI Engines – Development and Validation of a Virtual Injector Model”, ASME Trans., Journal of Fluids Engineering, Vol. 133, pp. 041304-1/14, 2011.

[3] Li, Y., Kirkpatrick, A., Mitchell, C., and Willson, B.,“Characteristic and Computational Fluid Dynamics Modeling of High-Pressure Gas Jet Injection”, ASME Trans., Journal of Engineering for Gas Turbines and Power, vol. 126, pp. 192-197, 2004.


AVL List GmbH

Siemens AG

Continental Automotive GmbH


The research activity was carried out within the InGAS

Collaborative Project of the European Community. The work was

aimed at characterizing the fuel jet properties and the evolution of

mixture formation in a direct injection CNG engine by means of

numerical simulations.

The simulation of methane DI into an engine is a challenging task,

due to the high pressure ratios which are used and to the

substantial difference in dimensions between the injector nozzle

and the cylinder, making the grid topology optimization quite hard.

Some examples of gas injection through a cylindrical orifice, by

means of ad-hoc mathematical models, can be found in literature,

but they are not suitable for the specific case of a poppet valve

injector. A ‘virtual injector’ approach, based on the use of sources

located in the nozzle sonic section, was then used to model the

injection of natural gas into the combustion chamber.

Laser-Induced Fluorescence images available from an optical-access single-cylinder engine were used to

validate the numerical results. A good agreement was obtained for different engine operating conditions.

The model was then used to analyze the effects of the injector protrusion in the combustion chamber, of the

injection timing, and engine operating conditions with reference to their impact on the jet stability and mixture

formation process. The experimental data on performance and emission of a 4-cylinder DI-CNG engine were

correlated with the results of the mixture formation analysis, in terms of mixture homogeneity or stratification

degree, so as to achieve a thorough knowledge of the DI CNG engine behaviour.

Influence of the injector position on

the jet equivalence ratio contours.

12.0

01.0

6.0

3.0

9.0


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First name: Luciano LAST NAME: ROLANDO

Topic: Hybrid Propulsion System

Course year: III Tutor(s): Federico Millo

Academic context Numerical Simulations

Hybrid Electric Vehicle

Powertrain Controller


Honda Europe – 2011 Honda Initiation Grant

Highlights of the research activity The aim of the research activity was the definition of an innovative comprehensive methodology to develop, through numerical simulations, a sub-optimal hybrid powertrain controller: starting from the definition of suitable performance indexes, the procedure analyzed the ideal performance of a case study hybrid architecture in order to point out information which could be used to define new control laws or to improve conventional methodologies. The majority of hybrid powertrain controllers implemented on a real vehicle are based on heuristic methods which are not computational heavy, but are quite far from the optimality. On the other hand, there are several methodologies, able to achieve results very close to ideal conditions, but not implementable because they require knowing in advance the mission profile. The main focus of this research activity therefore was on the development of a methodology capable to design a hybrid powertrain controller which can merge the strength of global optimization algorithm with the low computational requirement of heuristic strategies. The approaches based on the instantaneous minimization of a cost function (i.e. ECMS or adaptive ECMS) seem to be the most promising since they are both implementable and independent from driving condition while ensuring results not too far from the optimal ones, which can be achieved by global optimization algorithms. The energy management strategies, developed in the previous phases, have been integrated in detailed vehicle models and tested through numerical simulations over typical driving cycles. Globally, this methodology has provided an innovative and flexible mean to develop a sub-optimal hybrid powertrain controller which can take into account different tasks and constraints such as fuel consumption, NOx emissions or NVH issues.

Figure 1: Example of a vehicle model developed during the research activity.


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First name: ...........Uktam...................... LAST NAME: ........SALOMOV.......

Topic: “Pore-scale mesoscopic modeling of transport processes in electrodes for high temperature PEM fuel cells”

Course year: ....1.... Tutor(s): ....... prof. P. ASINARI.......

Academic context [ref 1] Jianlu Zhang et al. High temperature PEM fuel cells. Journal of Power Sources 160 (2006) 872–891 [ref 2] Succi, Sauro. The Lattice Boltzmann Equation for Fluid Dynamics and Beyond. Oxford University Press (2001). [ref 3] N. Jeong et al. Estimation of thermal and mass diffusivity in a porous medium of complex structure

using a lattice Boltzmann method. Int. J. of Heat and Mass transport, 51, (2008) 3912.


Research Centre ENEA-Brasimone

Prof. S. Ubertini, Università degli Studi di NAPOLI "Parthenope", Facoltà di INGEGNERIA, Dipartimento di PER LE TECNOLOGIE (within the project COFIN-PRIN 2008 "Microscopic modeling and degradation analysis of the membrane electrode assembly (MEA) in high temperature PEM fuel cells").


The first 6 months of my PhD study was devoted to the study of the transport processes in electrodes for high temperature PEM fuel cells by mesoscopic modeling.

In figure (top) the characteristic microstructure the polymeric electrolyte membrane is presented, taken by using electron microscopy (Research Centre ENEA-Brasimone).

As it is well known the most important relation describing fluid transport through such a structure (porous media) is Darcy’s law:

according to which, the permeability is proportional to the ratio between the flow rate through the porous media and the applied pressure gradient. To be able to apply Darcy’s law one has to make sure the flow is laminar.

On the other hand, permeability depends on porosity and other structural properties such as specific surface area, tortuosity, and shape and orientation of particles in the medium, are demonstrated and compared to those given by other methods, theory and experiment.

The mesoscopic method, namely Lattice Boltzmann method (LB) is used to calculate the permeability by numerically simulating a stationary (time-independent), pressure-driven flow through this media, by imposing a constant pressure at the inlet, and a constant, lower pressure at the outlet. The result of such simulation is presented in the figure (bottom), where stream lines as well as several slice of velocity profiles are plotted (in order to obtain this result I used PALABOS, open source software which is based on Lattice Boltzmann Method). Analytical relationships are then compared with the computational data.

Tomographic image of high temperature

PEM structure (top) and fluid flow (bottom)

in the matrix of pore space simulated with

the Lattice Boltzmann method. Colour bar

indicates the value of velocity.

http://en.wikipedia.org/wiki/Oxford_University_Press

http://en.wikipedia.org/wiki/Oxford_University_Press


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First name: ........Jacopo............................. LAST NAME: ........TONIOLO.......

Topic: .. Energy Monitoring in buildings: benchmark and control improvement..........

Course year: .2... Tutor(s): .Marco Masoero

Academic context

T.Sharp “Energy Benchmarking in Commercial Office Buildings”, 1996

W. Chung, Y. V. Hui, “A Study of Energy Efficiency of Private Office Buildings in Hong Kong”, Energy and Buildings, Pages: 696-701, 2009.

E. Beusker, C. Stoy, S. N. Pollalis, “Estimation model and benchmarks for heating energy consumption of schools and sport facilities in Germany”, Building and Environment, 2011.


Cardiff University, Welsh School of Architecture, prof. Ian Knight and Afroditi Konidari Intesa San Paolo (bank, 5'600 buildings in Italy)

ESAC (control system manufacturer)

Highlights of the research activity The research activity during 2011 was carried out on two main fields. The first was acquire the necessary knowledge about the System Identification methods applied to a building-HVAC system. This aim was accomplished buy develop some Black-Box regression methods and a control system for centralized heating systems. The second field was represented by the iSERV cmb project start up: make contact with owner/operators of HVAC systems to reach the the target of 150 buildings monitored by the end of 2012. The figure below represent a typical profile of electric consumption for an office building, created from hourly data.

Figure 2: carpet plot of global electric consumption in an office building (hourly data)

kW

h

Hour

of

the

day


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First name: Mattia LAST NAME: VENDITTI

Topic: Optimization of the operating strategy of a BAS hybrid diesel powertrain

Course year: 1st Tutor(s): Ezio Spessa

Academic context [ref 1] K. F. Man, K. S. Tang, S. Kwong, Genetic algorithms: concepts and applications, IEEE Trans. Ind. Electron., 43 (5), 1996. [ref 2] Z. Michalewicz, Genetic Algorithms + Data Structures = Evolution Programs. AI Series. Springer-Velag, New York, 1994. [ref 3] M. Ehsani, Y. Gao, S. E. Gay, A. Emadi, Modern Electric, Hybrid Electric, and Fuel Cell Vehicles: Fundamentals, Theory, and Design, CRC Press, 2005


GM Powertrain Europe

Highlights of the research activity A parallel-hybrid diesel powertrain with high-voltage belt alternator starter (BAS) was modeled in GT-Drive environment. The model implements all the BAS features, such as regenerative braking, Stop&Start strategy, load point shift and electric power assistance to the thermal engine. The hybrid operating strategy optimization was carried out in Matlab environment. The optimal power-split between the thermal engine and the electric machine is worked out by means of two innovative tools (benchmark optimizer and real-time optimizer) to minimize the fuel consumption, the NOx emissions and the combustion noise. A statistical solver, based on Genetic Algorithm techniques, was adopted to handle both the highly non-linear and non-continuous objective function and the huge number of variables (time-grid independence). The fuel consumption analysis was set up along the NEDC and real world representative driving patterns such as the Artemis cycles. The simulation along the NEDC showed how different optimization procedures (the working mode of the electric machine) lead to different battery state-of-charge profiles but do not introduce appreciable variations of the fuel consumption and do not affect the ICE temperature evolution. The optimization process along the Artemis cycles, instead, suggested to adopt the electric machine to shift the ICE load points toward the optimal operating line corresponding to the maximum efficiency. The NOx and combustion noise oriented optimizations were run only along the NEDC. The benchmark optimizer remarked how an intensive adoption of the MGU as generator to shift the ICE load points toward the minimum BSNOx is the key factor to drastically decrease the NOx emissions up to 50%. This result suggested to properly define the loss corresponding to the NOx emissions in the real-time optimizer. As the reduction of the NOx emissions can be an order of magnitude greater than the FC benefits, a PHEV architecture with an on-board diesel engine and BAS should more likely to be addressed to optimize the pollutant emissions. The HOS was also targeted to reduce the local combustion noise peaks during low speed transients. Different types of calibration were built to test the effectiveness of the method during the most critical phases. The real-time optimizer was built in order to minimize integral objectives (fuel consumption and NOx emissions) and maximize local improvements as well (combustion noise peaks).

Powertrain Layout of a Belt Alternator

Starter

EM

Inverter Battery

ICE Gearbox

Mechanical path

Electrical path


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First name: DAVIDE SIMONE LAST NAME: VEZZA

Topic: Experimental investigation of different after-treatment technologies for the reduction of pollutant emissions from automotive Diesel engines.

Course year: 3 Tutor: Prof. Federico Millo

Academic context [ref 1] Pischinger, S., Körfer, T., Wiartalla, A., Schnitzler, J., Tomazic, D., Tatur, M., “Combined Particulate

Matter and NOx Aftertreatment Systems for Stringent Emission Standards”, SAE World Congress & Exhibition, April 2007, Detroit, MI (USA), DOI: 10.4271/2007-01-1128.

[ref 2] Johnson, T.V., “Diesel Emissions in Review”, SAE 2011 World Congress & Exhibition, April 2011,

Detroit, MI (USA), DOI: 10.4271/2011-01-0304.

[ref 3] Khair, M., Millo, F., “Diesel Exhaust Aftertreatment 2000-2007”, SAE International, 2008.


General Motors Powertrain Europe

Highlights of the research activity Currently, two consolidated aftertreatment technologies are available for the reduction of NOx emissions from diesel engines: Urea SCR (Selective Catalytic Reduction) systems and LNT (Lean NOx Trap) systems. Urea SCR technology, which has been widely used for many years at stationary sources, is becoming nowadays an attractive alternative also for light-duty diesel applications. However, SCR systems are much more effective in NOx reduction efficiency at high load operating conditions than light load condition, characterized by lower exhaust gas temperatures. One possible solution to improve the low temperature behavior, is the use of newly developed Advanced Diesel Oxidation Catalysts (A-DOC) which are capable to store NOx at low exhaust temperatures (typical of urban driving conditions) when SCR efficiency is low, and to release the stored NOx at higher temperatures (i.e. during extra-urban driving conditions) where the urea injected is effectively forming ammonia for the subsequent NOx conversion. The characterization of these newer DOC formulations is performed exposing the A-DOC to emissions coming from a modern Euro 5, 2.0 L displacement turbocharged Common Rail DI Diesel engine for a typical European passenger car, while driving NEDC cycles; the engine features a DOC and a DPF in close-coupled position, hosted into an on purpose designed dismountable canning, thus allowing an easy switch between different components. Catalysts were tested both in fresh and hydrothermally aged conditions in order to have a better understanding relative to robustness and durability of these newer catalyst. NOx storage capability was found to be impressively high for a fresh A-DOC, while significantly decreased after aging, thus leading to a final DPF-out NOx cumulated emissions figure which equals the engine-out value for the aged A-DOC.

Figure - Dismountable canning hosting the A-

DOC.


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First name: THEODOROS LAST NAME: VLACHOS

Topic: Experimental investigation on performance and emissions of an automotive Diesel Engine fuelled with biofuels

Course year: 2nd Tutor: Prof. Federico MILLO

Academic context Abdul-Khalek I. S., Kittelson D. B., Graskow B. R., and Wei Q.: “Diesel Exhaust Particle Size: Measurement

Issues and Trends”, SAE Technical Paper 980525, 1998. Guido C., Beatrice C., Di Iorio S., Fraioli V., Di Blasio G., Vassallo A. and Ciaravino C.: “Alternative Diesel

Fuels Effects on Combustion and Emissions of an Euro5 Automotive Diesel Engine”, SAE Technical Paper 2010-01-0472, 2010.

De Filippo A., “Particle Size and Number Emissions from Modern Light-Duty Diesel Vehicles”, SAE Technical Paper 2011-01-0632, 2011.


General Motors Powertrain Europe (GMPTE)

Highlights of the research activity In recent years biofuels have attracted considerable attention as renewable and able to reduce oil dependency and greenhouse emissions. Recent European directives introduced a new target for the European Union (EU) member states concerning the share of energy from renewable sources in all forms of transport; in particular a target of at least 10% of the final energy consumption in transport should be achieved by 2020. Today, biodiesel is the biofuel most commonly used in Europe, covering approximately 80% of the biofuel market. Since the biodiesel usage appears to be particularly challenging in small displacement engines, due to the high risks of lube dilution caused by cylinder liner fuel jet impingement occurring during post-injections used for DPF regeneration and due to the increased risk of injector nozzle coking in small diameter nozzle holes, a more exhaustive evaluation of biodiesel usage effects on small displacement modern diesel engine is needed. Therefore, the aim of this research activity, still in progress, is to evaluate the effects of using blended (30% vol.) biodiesel, obtained from Rapeseed Methyl Ester (RME) and renewable diesel fuel sourced by Hydrotreated Vegetable Oil (HVO), in a last generation small displacement passenger car diesel. The impact of a biofuel blend usage, in terms of performance and emissions, is studied at both full and part load operating conditions.


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First name: .....Yingying................................... LAST NAME: ......YANG..............................

Topic: ....Solar energy as a renewable resource for cooling..............................

Course year: .... 3rd Year.... Tutor(s): .....G. V. Fracastoro.......

Academic context [ref 1] C. A. Gueymard, D. R. Myers, Evaluation of conventional and high-performance routine solar radiation measurements for improved solar resource, climatological trends, and radiative modeling, Solar Energy, Volume 83, Issue 2, February 2009, Pages 171-185. [ref 2] F. Calise, M. Dentice d’Accadia, A. Palombo, Transient analysis and energy optimization of solar heating and cooling systems in various configurations, Solar Energy, Volume 84, Issue 3, March 2010, Pages 432-449. [ref 3] U. Eicker, D. Schneider, J. Schumacher, T. S. Ge, Y. J. Dai, Operational experiences with solar air collector driven desiccant cooling systems, Applied Energy, Volume 87, Issue 12, December 2010, Pages 3735-3747.


ECOJOULE: Helios-HP project

FRIGORIFERI BAVA: Helios-HP project

IPLA (Istituto per le Piante da Legno e l’Ambiente): PUEEL Project

Highlights of the research activity 1. Measurements of solar beam normal irradiance and solar global horizontal irradiance all through

2010; comparison of measured data and clear-sky model; calculation of atmospheric turbidity factors for clear-sky days and comparison with 1975-76 data.

2. Sensitivity analysis of solar cooling systems with various configurations (collector area and type, storage volume, load, location) with software Polysun.

3. Field data analysis of solar collector systems at various sites in Piemonte and solar cooling system in IPLA; preliminary design of solar cooling test rig for the Helios-HP project.

4. Main conclusions: The ASHRAE clear-sky model mostly fits the solar beam normal irradiance while the solar diffuse radiation factor ‘C’ is simpler since the C varies all through a day; The turbidity factors are lower in 2010 during winter time due to usage of cleaner fuels and district heating while during summer they increase due to heavier traffic; solar cooling system simulations show that solar factor increases as the solar collectors’ areas are larger while it decreases as volume sizes of storage tank are bigger.

5. Publication in 2011: Fracastoro G. V., Yang Y. Y., Coppa G., Simonetti M., Atmospheric turbidity measurements in Torino: A comparison between 1975 and 2010, ISES Solar World Congress 2011.

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Comparison of Turbidity Factors between 1975-6 and 2010 in Turin

EENNEERRGGEETTIICCSS PPhhDD PPRROOGGRRAAMM … · Areva NP Inc. - Paris Highlights of the research...

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