Real Time GT-POWER Simulation for Emission Prediction … · Real Time GT-POWER Simulation for...
Transcript of Real Time GT-POWER Simulation for Emission Prediction … · Real Time GT-POWER Simulation for...
Real Time GT-POWER Simulation for Emission Prediction for Engine Verification
Elias Johansson, Volvo GTT Gothenburg
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Request: More robust engine emission verification Tool: ”Virtual Test Rig” for Transient Cycle Emission Simulations using Engine/EATS/vEMS-model with live SiL control
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Presentation Agenda
System overview and description
Model development process
Correlation of model to real system behaviour
Cycle simulation results
Delivery for certification process of Volvo EuVI engine
Questions
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Simulation System Overview
Application and live monitoring
of EMS in ATI Vision Operating control in engineSIL
vEMS (compiled EMS) + DST vEMS software + DST
Simulation strategy
GT-Power RT Engine model
Volvo EATS model
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Simulation System Overview
GT-Power RT Engine model
Volvo EATS model vEMS (compiled EMS) + DST vEMS software + DST
Simulation strategy
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Simulation System Overview Operating control in engineSIL
vEMS
Engine model
EATS model (DOC+DPF+SCR
with urea buffer)
Actuators
Sensors
Control
Demand
Actuators
Sensors
Drive cycle and Environment
Road cycle/Engine test
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Simulation System Overview Operating control in engineSIL
vEMS
Engine model
EATS model (DOC+DPF+SCR
with urea buffer)
Actuators
Sensors
Control
Demand
Actuators
Sensors
Drive cycle and Environment
Matlab
Logging signals
Road cycle/Engine test
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Simulation System Overview Operating control in engineSIL
vEMS
Engine model
EATS model (DOC+DPF+SCR
with urea buffer)
Actuators
Sensors
Control
Demand
Actuators
Sensors
Drive cycle and Environment
Matlab
Compare to test data
Calculate Fuel Consumption,
WBW NOx etc.
Road cycle/Engine test
Matlab
Logging signals
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Processing of Simulation and Results
Matlab script for:
Running pre-specified simulations
Storing/writing of sampled data (to Excel)
Easy plotting/comparison of results
Calculating WBW-NOx and other parameters
Matlab
System requirements for finished coupled and evaluated model
PC with one Matlab/Simulink license
Simulation speed on 2.4GHz PC ~ 4 times faster than RT
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Model Development Process
Detailed engine model calibrated
to HW engine in 35 SS points
DOE of 8000 experiments
with 8 input parameters
Transient calibration
of MV (RT) model
Wall Temp Solver, Turbo inertia
Filtering NN outputs
Actuator delays
RT model coupled to vEMS
and EATS models in Simulink
∆T=
100°C
70s 300s
System evaluation in
Vision
Mode coordinators
Nox sensors
Urea dosing/buffering
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Engine Model
MV cylinder with neural networks trained from detailed model with
injection, combustion and NOx model. Cylinder trained within large
ranges of dependent parameters.
Eng rpm, Boost T, Boost P, Exh P, Fuel mass, SOI, Fuel P, EGR-fraction
predictive in wide range of engine running conditions
Physical properties retained from detailed GT-Power model (flow and
temperatures solved through the whole system). Turbo and EGR
circuit outside of MV-dependency
Faster than RealTime (~4times)
Physical interpretation of transients through thermal masses (transient
wall temp solver) in intake and exhaust system
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Engine Model
Turbo and EGR circuit modeled externally - same MV cylinder can
be combined with different Boosting and EGR systems
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Engine Model – Calibration process
Detailed model
Calibrated to Steady State test data for EuVI engine
MV-model
Refined calibration to test data (pulsating flow steady flow)
Dynamic ”lag” calibration of NN engine parameters and actuators
”Fast” temp sensor measurment for calibration of engine ExhMan temp
Transient calibration to measured cycle data and on-road PEMS
- Thermal mass, inertias, sensor slowliness
(Crucial for good prediction of SCR NOx conversion )
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Calibration Results of EuVI MV model
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Calibration Results of Eu6 MV model
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Closed Loop Model Interaction
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Closed Loop Model Interaction
T T T NOx NOx 𝒎 Urea
T exh
𝐦 exh
dP
EO Nox
EO O2frac
𝒎 HC
Engine
sensors
Engine
Actuators
vEMS
SOI
Inj P
Mfuel
EGR Valve
Exh Valve
ITV
WG
Pboost
Tboost
Texh
Pexh
Eng rpm
Eng Torque
Turbo rpm
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Model Transient Calibration
Correlation of ” real gas temperature” in exhaust through comparison
to transient cycle measured with fast Temp sensor
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Thermal mass
tuned
Without
Thermal mass
measured simulated
Model Transient Calibration
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Correlation of ” real gas temperature” in exhaust through
comparison to WHTC cycle with fast Temp sensor
Validation of temperature sensors and SCR functionality
through comparison to long road cycle with Urea and NOx
measurement
Model Transient Validation
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Model Transient Validation (ExhTemps and NOx conv.) Exhaust Temp
sensor value
SCR Temp
sensor value
NOx Eng out
NOx Syst out
Urea inj mf
DPF Temp
sensor value
measured simulated
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Model Transient Validation
Steady State correlation (to measured data)
Within 2% of flow, temperatures and pressures
Transient correlation (to measured data)
1.1% BSFC over ISC (4h road) cycle
4.2% Engine out NOx over ISC cycle
8.1% System out NOx over ISC cycle
2.9% Urea consumption over ISC cycle
<30% SO NOx over WHTC, WHSC and WNTE cycles (incl low temp/high alt.
conditions )
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Correlation of ” real gas temperature” in exhaust through
comparison to transinet cycle with fast Temp sensor
Validation of temperature sensors and SCR functionality
through comparison to long road cycle with Urea dosing
and NOx measurment
Model Transient Validation
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Drive Cycle
Environment ( Ambient Pressure, Temperature)
Software / Dataset
We can now run predictive simulations of any:
Transient behaviour of temperatures in exhaust system are correlated with
respect to thermal mass
NOx conversion is validated from different cycles and running conditions
Model Transient Validation
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Useful Areas
Evaluation of new software and control strategies, heat modes etc
Early calibration work, extended EMS engine model etc.
Prediction of fuel (and urea) consumption and NOx emissions
Cycle simulations at warm/cold temperatures and high altitude
Robustness study on sensor/actuator variance (system level)
Regeneration strategies, ageing/poisoning of EATS
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Database Simulation for EuVI Certification
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
Euro VI Emission Requirements
World Harmonised Steady State & Transient Cycles
(WHSC & WHTC)
Off-cycle emissions (OCE)
- World Harmonised Not-to-Exceed (WNTE) test
In Service Conformity (ISC)
- 4h road cycle incl. 15min stop
- Max WBW NOx requirement
All Certification cycles in test rig and on road was complemented
with simulated cycles at high altitude + warm and cold temperatures
In total ~200 cycles for 1 EuroVI engine concept were simulated
Volvo GTT, GOT Elias Johansson, System Analysis & Simulations
2012-11-05
The End
Thank You for Your kind attention!
Questions?