Turbo compressor test bench operational · Two gas bottles of helium and neon with their pressure...

Turbo compressor test bench operational

EASITrain-P1-WP4-MS7

EDMS 2042000

Date: 15/02/2019

Grant Agreement 764879 PUBLIC 1 / 15

Grant Agreement No: 764879

EASITrain European Advanced Superconductor Innovation & Training

MILESTONE REPORT (MS7)

TURBO COMPRESSOR TEST BENCH OPERATIONAL

Document identifier: EASITrain-P1-WP4-MS7

EDMS 2042000

Due date: End of Month 17 (March 1st 2019)

Report release date: 15/02/2019

Work package: WP4 (Cryogenics)

Lead beneficiary: USTUTT

Document status: RELEASED (V1.0)

Abstract:

This milestone report concerns the successful establishment of a turbo compressor test rig at the

University Stuttgart (Germany) as a result of a collaborative effort of the University Stuttgart,

University Dresden, CERN and company MAN, all participants in the EASITrain project.

A description of the test rig architecture is first given as well as the objective of the measurement

campaign. The procedure followed to operate the test rig and measure the compressor performance is

described. The model used to predict the test rig behaviour during operation is also briefly shown. The

last section is dedicated to giving an exhaustive list of the components, which are part of the test rig.



EDMS 2042000

Date: 15/02/2019


Copyright notice:

Information provided with this document is subject to the H2020 EASITrain – European Advanced

Superconductivity Innovation and Training grant agreement. This Marie Skłodowska-Curie Action

(MSCA) Innovative Training Network (ITN) receives funding from the European Union’s H2020

Framework Programme under grant agreement no. 764879. Copyright 2017.

Delivery Slip

Name Partner Date

Authored by Maxime Podeur CERN 15/01/19

Edited by Coralie Hunsicker CERN 15/01/19

Reviewed by Johannes Gutleber CERN 04/02/19

Approved by M. Benedikt, A. Ballarino 15/02/19



EDMS 2042000

Date: 15/02/2019


TABLE OF CONTENTS

1. CONTEXT ................................................................................................................................................................ 4

2. TEST RIG DESCRIPTION .................................................................................................................................... 5

2.1. OVERVIEW ......................................................................................................................................................... 5 2.2. TURBO COMPRESSOR .......................................................................................................................................... 7

3. TEST RIG OPERATION ........................................................................................................................................ 8

3.1. MEASUREMENT PROCEDURE .............................................................................................................................. 8 3.1.1. Gas mixture preparation ............................................................................................................................ 8 3.1.2. Test loop filling ........................................................................................................................................... 9 3.1.3. Test loop operation ..................................................................................................................................... 9

3.2. PERFORMANCE PREDICTION ............................................................................................................................. 11

4. BILL OF MATERIALS ........................................................................................................................................ 12

5. ANNEX GLOSSARY ............................................................................................................................................ 15



EDMS 2042000

Date: 15/02/2019


1. CONTEXT

This document reports on the successful achievement of the milestone to establish a turbo compressor

test rig at the University of Stuttgart (Institute of Thermal Turbomachinery and Machinery laboratory,

Pfaffenwaldring 6, 70569 Stuttgart, Germany). The test rig has been designed as a cooperative effort

of early stage researchers ESR 15 (U. Stuttgart) and ESR 11 (TU Dresden) within the EASITrain

project. The materials for the infrastructure are provided in the frame of collaboration agreement FCC-

GOV-CC-0126/EDMS 1843485/KE3854/ATS between the University of Stuttgart and CERN. The

infrastructure is provided by the University of Stuttgart.

Within the framework of the Future Circular Collider study for a new particle collider research

infrastructure, novel methods for cost and energy efficient cryogenic refrigeration are investigated.

While state-of-the-art screw compressors remain a viable option in a standard helium cryogenic cycle,

by ballasting the operating fluid with a heavy gas such as neon, the usage of a multi-stage turbo

compressor becomes realistic. This new approach builds on collaborative research to work on a novel

turbo compressor for light gases between company MAN Energy Solutions and the Institute of

Thermal Turbomachinery and Machinery Laboratory at the University of Stuttgart. The main goal of

this research group is to provide an efficient and economically viable solution for the multi-stage turbo

compressor.

Using neon as a ballast gas, the resulting neon-helium gas mixture remains particularly light. Impellers

used in industrial multi-stage compressor today are not optimised for such light gases. For this reason,

new impellers have to be designed and thus, having a turbo compressor test rig is necessary to measure

their performance in the field and study the advantage and limitation of this operating gas.

The achieved milestone consists of a comprehensive architecture and design of the test rig, the ordered

components and the established setup that serves throughout the EASITRain project and beyond for

the design and in-field validation of a novel turbo compressor. At this point in time the test rig does

not yet include a novel turbo compressor. The design of a first prototype of the novel turbo compressor

has been finished. The manufacturing is ongoing. A second impeller is currently being designed and

as a result of an academia/industry co-innovation process. This will lead to the design of a new multi-

stage turbo compressor for energy efficient cryogenic refrigeration.



EDMS 2042000

Date: 15/02/2019


2. TEST RIG DESCRIPTION

2.1. OVERVIEW

The figure below shows the test rig P&ID including the different components as well as the

measurement and control connection.

Figure 1: Test rig P&ID

Two areas of the test rig can be distinguished:

In the upper left of the scheme, the gas mixture is prepared, stored and its properties are

analysed. This part of the test rig includes:

Two gas bottles of helium and neon with their pressure reducing valves

A buffer tank used to store and prepare the gas mixture

A gas analyser to measure precisely the proportion of the two gases in the gas mixture

A pump to drive the flow from the buffer tank towards the gas analyser and back to the

buffer tank as well as to remove part or all the gas from the test loop and store it into

the buffer tank

Pressure and temperature sensors required for the gas mixture preparation



EDMS 2042000

Date: 15/02/2019


Valves needed for the preparation of the gas mixture as well as to isolate this part of

the test rig from the test loop itself.

The remaining components are part of the so-called test loop, where the turbo compressor

performance is tested. Thus, it includes:

The turbo compressor (in a first step, a compressor designed by USTUTT is used to

bring the test rig in operation and gather experience. In a second step, the test rig will

be used to test and validate novel developments. The test rig is needed to perform this

multi-step development process);

An after cooler reduces the compressor outlet temperature and maintains the desired

compressor inlet temperature. This after cooler is connected to the facility water supply

as well as to a throttle valve used to regulate the water volume flow going through the

heat exchanger;

A Venturi flow meter enabling the evaluation of the gas mass flow rate inside the test

loop;

A flow settling tank connected to the buffer tank and used to facilitate the mixing of

gas from or towards the buffer tank as well as to prepare the flow before entering the

compressor. This becomes possible by reducing the flow velocity and thus removing

potential flow instabilities generated from the upstream bends and the mixing flows;

Pressure and temperature sensors to measure the flow thermodynamic properties in

different position of the test loop as well as to estimate the gas mass flow rate going

through the Venturi flow meter;

Two throttle valves to regulate the compressor inlet pressure;

Two manual valves used respectively to vacuum the test loop or the entire test rig and

to flood the test loop with air when operation is required on it while the gas mixture is

safely stored in the buffer tank.

A detailed list of the test rig components is given in section 4.



EDMS 2042000

Date: 15/02/2019


2.2. TURBO COMPRESSOR

The heart of the test loop is a turbo compressor. The operating gas being light, an ultra-high-speed

motor is required to obtain a significant pressure increase through the compressor stage. An extensive

market research concluded that the only viable option fulfilling the requirements in terms of size and

rotational speed today is met by a product offered by FISCHER. Figure 2 shows a picture of this

device.

Figure 2: Turbo compressor EMTC-120K

The EMTC-120K reaches rotational speeds up to 120,000 RPM with a rated input power of 17 kW.

In total, three different impeller designs will be mounted and tested on the rig. The first impeller has

been designed with the objective of having a first efficient and robust design capable of exploring a

wide range of gas mixtures and uses the entire operating range provided by the motor. The latter will

be particularly useful to determine a correlation on the effect of changing the gas mixture on the

compressor performance. This correlation will then be needed to scale the compressor up to the real

size application. Hence, the first compressor will serve as an exploratory design. The 3D geometry of

the latter and its performance are shown on the figure below:

Figure 3: Impeller geometry (on the left) and compressor performance map (on the right)



EDMS 2042000

Date: 15/02/2019


The second design currently being investigated will be developed in cooperation with MAN Energy

Solutions so that all the condition and limitation imposed by their multi-stage machine, i.e. the so

called HOFIMTM, are taken into account. Hence, once a suitable geometry will have been designed for

this machine, the impeller will be scaled down, mounted on the test rig and its performance tested. The

performance of the real size machine will then be obtained based on a correction of these measurements

using the correlation previously mentioned.

3. TEST RIG OPERATION

3.1. MEASUREMENT PROCEDURE

The following section is dedicated to the description of how the test rig is operated and how the

performance of the compressor is measured.

3.1.1. Gas mixture preparation

The gas mixture is prepared in the buffer tank next to the test loop. Before preparing the gas mixture,

the mass of gas required inside the test loop has to be calculated and based on this estimate, a suitable

mass of gas has to be prepared inside the buffer tank. This mass of gas directly translates into a final

pressure for a given temperature.

Then, depending on the objective gas mixture, an intermediary pressure for the first gas to be added

can be calculated. The set pressure on the pressure reducing valve of the first gas bottle is progressively

increased towards this target intermediary pressure. The butter tank temperature and pressure given on

the control panel, have to be monitored closely. Once the intermediary pressure is reached, shut off

valves for the first gas bottle are closed and the set pressure on the second gas bottle is increased

towards the final pressure. Shut off valves of the second gas bottle are then closed.



EDMS 2042000

Date: 15/02/2019


Figure 4: Control panel for the gas mixture preparation

Once the desired pressure is obtained, the mole fraction of both gases can be measured using the gas

analyser. To do so, the manual valve separating the pump and the gas analyser is opened. Gas can then

circulate through the gas analyser and the mole fraction of helium in the mixture is then given on the

control panel. If the gas mixture does not correspond exactly to the desired composition, then the latter

can be fine-tuned by progressively adding one of the two gases until the desired gas mixture is reached.

3.1.2. Test loop filling

Once the gas mixture has been prepared, the set pressure of the pressure reducing valve separating the

buffer tank and the test loop is then increased to the desired pressure corresponding to the mass of gas

needed to run the test loop. This mass of gas is evaluated in advance depending on the gas mixture and

the compressor condition of operation at the first speed line of the compressor map. The shut off valve

placed downstream of this valve can then be opened to let the gas flow inside the test loop. Once the

pressure is reached, this shut off valve is then closed.

3.1.3. Test loop operation

The test loop can now be operated. The two shut off valves separating the test loop and the buffer tank

are thus closed. The motor is then switched on and its rotational speed progressively increased towards

the first rotational speed directly from the control panel shown on figure 6. In parallel, the temperature

downstream of the heat exchanger is reduced to match the target compressor inlet temperature by

automatically adjusting the water throttle position. Moreover, the two gas throttle valves are used to

adjust the compressor inlet pressure in order to end up close to the choke region of the compressor

map.



EDMS 2042000

Date: 15/02/2019


Each speed line of the compressor map is then covered first by reducing the compressor inlet pressure

with the help of the throttles and a second time by reducing the amount of gas inside the test loop. Gas

can be easily removed from the test loop by simply opening the electro-pneumatic operated shut off

valve placed between the test loop and the pump driving the flow towards the buffer tank. The

evolution of the compressor inlet pressure and the mass of gas for respectively the first and second run

on the same speed lines are given on figure 5.

Figure 5: Gas mass (on the left) and compressor inlet pressure (on the right) variation for different speed lines

The operating point position on the compressor map can be followed on the control panel, where the

mass flow is given as a reduced quantity in order to remove the effect of the compressor inlet pressure

and mass of gas.

Figure 6: Control panel for the test loop operation



EDMS 2042000

Date: 15/02/2019


3.2. PERFORMANCE PREDICTION

A Simulink model has been developed to predict the flow properties in different parts of the test loop

depending on the compressor operating point. Part of this block model is shown on the figure below:

Figure 7: Simulink model used for the prediction of gas properties inside the test loop

Hence, based on the compressor performance map and by estimating the pressure drops in the different

parts of the test loop, the pressure and flow velocity can be estimated as shown below.

Figure 8: Gas pressure (on the left) and flow velocity (on the right) evolution in the test loop

This model is particularly useful to predict the test rig behaviour when operated. Therefore, the large

variation of flow properties that the sensors and valves will see during the test rig operation can be

easily predicted and used when sizing the different components. Finally, this model will be fine-tuned

with the measurements data.

0 1 2 3 4 5 6

Length [m]

1

1.05

1.1

1.15

P [P

a]

105

Compressor

Pipe

Bend

HE

Venturi

Tee

Throttle

Conv/Div

Flow conditioner

0 1 2 3 4 5 6

Length [m]

0

5

10

15

20

25

C [

m/S

]

Compressor

Pipe

Bend

HE

Venturi

Tee

Throttle

Conv/Div

Flow conditioner



EDMS 2042000

Date: 15/02/2019


4. BILL OF MATERIALS

N° Component Company Reference Qty

1 Vacuum pump ITSM - 1

8 Diaphragm pump Leybold DIVAC 0.8LT 1

2 After cooler API - 1

3 Temperature control system ITSM - 1

4 Turbo compressor + motor + inverter Fischer EMTC-120K 1

9 Cryostat LAUDA MC 1200 1

Table 1: Compressor, pumps, heat exchanger


7-1 Pressure reducing valves gas bottles Air Liquide HBS 200-3-3,5 2

7-2 Manual shut off valves Pfeiffer PF D31 033 4

7-3 Operated shut off valves Pfeiffer PF D38 24 2

7-4 Safety valves Goetze Armaturen

428tGFO-15-f/f-15/15 FKM 1

7-7 Pressure reducing valve Swagelok KPR1DFC412A20000 1

Table 2: Valves


7-5-1 Gas throttle DN16 Idealvacuum P108390 1

7-5-2 Gas throttle DN50 Idealvacuum P108185 1

7-6 Water throttle ITSM - 1

Table 3: Throttles


5 Frame Etb eus - 1

6-1-1 PN6 DN16 SS1.4301 3810mm Etb eus - 1

6-1-2 PN6 DN50 SS1.4301 5314mm Etb eus - 1

6-1-3 PN6 DN63 SS1.4301 334mm Etb eus - 1

6-1-4 PN6 DN100 SS1.4301 300mm Etb eus - 1

6-1-5 Tee PN6 DN16 SS1.4301 Etb eus - 7

6-1-6 Bend PN6 DN16 SS1.4301 Etb eus - 21

6-1-7 Bend PN6 DN50 SS1.4301 Etb eus - 5

6-1-8 Expender/Reducer DN100 to DN50 Etb eus - 2

6-2 Buffer tank 61L Etb eus - 1

6-3 Pressure ring Etb eus - 4

6-4 Venturi flow meter Etb eus - 1

Table 4: Pipes



EDMS 2042000

Date: 15/02/2019



10-1-1 Flange short DN16 NOVOTEK 1532 19

10-1-2 Flange long DN16 NOVOTEK 1521 1

10-1-3 Flange short DN50 NOVOTEK 1537 1

10-2 Clamp NOVOTEK 1301 35

10-3-1 O-ring DN16 NOVOTEK 1092 25

10-3-2 O-ring DN50 NOVOTEK 1095 10

10-4 Adapter VCR KF NOVOTEK 1831-14 4

Table 5: Vacuum flanges


13-1-1 Absolute pressure transducer Siemens 7MF1565-5BD00-1CA1 2

13-1-2 Absolute pressure transducer Siemens 7MF4233-1GA00-2AA6 4

13-1-3 Differential pressure transducer Siemens 7MF4433-1EA02-2AA6 1

13-3 Gas analyser SRS BGA244HP 1

13-4-1 Thermocouples Roessel STE-1KE-1.0-150 2

13-4-2 RTD PT1000 4 wires Roessel WB-3.0-1 Pt-AA-150 7

Table 7: Sensors


13-4-3 Sensor fixation Swagelok -6M0-1-2RP 9

13-2-1 Probe total pressure ITSM - 2

13-2-2 Probe total temperature ITSM - 2

Table 8: Additional components for sensors


14-2-1 DAS Delphin EK200 1

Table 9: Data acquisition system


14-1-1 CPU 1214C Siemens 6ES7214-1AG40-0BX0 1

14-1-2 Analog out Siemens 6ES7232-4HD32-0XB0 1

14-1-3 Module CANOpen HMS CM CANOpen 1

14-1-4 Power supply Siemens 6EP1332-1SH71 1

14-1-5 Analog input TC Siemens 6ES7231-5QF32-0XB0 1

14-1-6 Communication RS232 Siemens 6ES7241-1AH32-0XB0 2

Table 10: PLC



EDMS 2042000

Date: 15/02/2019



16-1 Helium 4.6, 50L, 200bar Air Liquide 6ES7214-1AG40-0BX0 1

16-2 Neon 4.0, 50L, 200bar Air Liquide 6ES7232-4HD32-0XB0 1

Table 11: Gas



EDMS 2042000

Date: 15/02/2019


5. ANNEX GLOSSARY

SI units and formatting according to standard ISO 80000-1 on quantities and units are used throughout

this document where applicable.

FCC Future Circular Collider

FCC-ee Electron-positron Collider within the Future Circular Collider study

FCC-hh Hadron Collider within the Future Circular Collider study

HL-LHC High Luminosity – Large Hadron Collider

LHC Large Hadron Collider

Turbo compressor test bench operational · Two gas bottles of helium and neon with their pressure...

Documents

Transcript of Turbo compressor test bench operational · Two gas bottles of helium and neon with their pressure...