Http:// WP 3: Thermal System Strictly Confidential 1 Workpackage 3: Thermal System Project Meeting, May 11, 2006

http://www.nonmet.mat.ethz.ch/research/onebatWP 3: Thermal SystemStrictly Confidential 1

Workpackage 3: Thermal System

Project Meeting, May 11, 2006

P. Müller, A. Bolleter, M. Roos, A. Bernard

NTBINTERSTAATLICHE HOCHSCHULEFÜR TECHNIK BUCHS

NMW


Outline

▪ Overview Work Package and Concept

▪ Thermal Demonstrator and measured Temperature Distribution

▪ Comparison with Simulation

▪ Modified Concept

▪ New Power Ranges

▪ Next Steps and Summary


Overview Workpackage 3

Thermal System

concept, fabrication &measurement

concept, simulation

NMW

NTBINTERSTAATLICHE HOCHSCHULEFÜR TECHNIK BUCHS

design, simulation, measurement design, fabricationdesign, fabrication

CathodeElectrolyte

Anode

Air

Fuel

Reformer

Heat exchangerPost

combustion


Project Management

Thermal System

Fuel Cell

Gas Processing

WP 3: Year 1 Milestones

• performance 200 mW/cm2 @ 550°C• external electrical connections

• thermal insulation concept with Tinside 550°C, Toutside 50°C, <10 cm3

• structures for validation critical points• thermal system demonstrator with simulated 2 W heat source

• butane conversion rate > 90%• post-combustor with gas oxidation

> 98%

• battery expert• industrial partner


Main Achievements

Simulation validated with Thermal Demonstrator.


Overview Concept and Simulation

Thickness of Stack [mm]

Sta

ck t

em

pe

ratu

re [

°C]

Stack

Heat Exchanger

Insulation

Stack Heat Exchanger

Insulation

Thickness heat exchanger (Mica) [mm]

Sta

ck R

ad

ius

[mm

]

Distribution Heat Flow


Demonstrator with Resistance Heat SourceFoturan Dummy-Stack

MICA

Insulation Element

Contact Heater


Measured Temperature distribution

Insulation thickness: Microtherm 6 mmConstant Heating Power: 2 W

350°C

40°C

7 min for constant temperature

Stack temperature 350 °C and 40°C in surrounding area


Temperatures with different Insulations

Aerogel 10 mm, Mica 70 µm

Microtherm 21 mm, Mica 50 µm

Microtherm 6 mm , Mica 50 µm [°C]

Thicker insulation does not change the stack temperature

With transparent Aerogel lower stack temperature

40

43

38

30

23

35

295

369

349

Constant Heating Power: 2 W


Simulation of Demonstrator: Temperature Distribution 1

Microtherm thickness 6 mm with radiation and MICA 0.5 W/mK

Microtherm thickness 6 mm no radiation and MICA 0.5 W/mK

395 °C 750 °C

40°C 40°C


Simulation of Demonstrator: Temperature Distribution 2

Microtherm thickness 6 mm with radiation and MICA 0.5 W/mK

Microtherm thickness 6 mm with radiation and MICA 4 W/mK

364 °C395 °C

40°C 40°C


Comparing Demonstrator with Concept

Difference of demonstrator to thermal concept- Channel height- Radiation in concept along channel not considered- Gas flow in the channels (Manufacturing)

Conclusion- Measurement correlates with simulation (demonstrator)- Thermal conductivity of mica has influence on stack temperature- Radiation along channel has strong influence on stack temperature

Modification of concept needed

Demonstrator Thermal Concept µSOFC


Modification of Concept

Advantages:- Fabrication, mica no bonding needed- Reduced thermal strain- Reduced thermal radiation

Disadvantages:- Heat exchanger performance lower- Pressure drop higher

Stack

Fuel Supply

MICA Heat Exchanger Air

Temperature Distribution

550°C 220°C

40°C

First result, research going on


New Power-Range

Basic Scaling Properties (first design approach)

• Stack structure is modular

• Stacking of units is “Milli”-scopic (=conventional technology)

• Thermal System not scalable: Adaptation of concept necessary

• Thermal Management comparably simpler (surface to power ratio)

Main Issues to be solved

• Adapted concepts of insulation for each power range

• Fabrication: concept of “modular” system (planar technology)

• Layout and Manufacturing of gas and air channels, electric connection


Validation of Milestones and Deliverables

• WP 3.2 Fabrication Concept of Thermal System

Month 6: test structures for validation of critical points of the concept (T

diff. 500°C) (NTB)

Month 12: thermal system design demonstrator with simulated heat sources

(dummy stack, reformer, post-combustor) (NTB)

• WP 3.1 Thermal System Design

Month 3: thermal insulation concept (Tinside = 550°C, Toutside = 50°C) (ZHW)

Month 12: system integration concept incl. thermal management concept heat

exchanger design compatible with GPU designs and micro-fabrication (ZHW)

Deliverables:

Month 3: design from ZHW NTB for fabrication

Deliverables:

Month 6: first samples of GPU from NTB LTNT for testing

Specification to be revised

Specification to be revised


Summary

▪ Thermal Demonstrator shows 350 °C with 2 W

▪ Consistent between Simulation and Measurement

▪ Modification and Adaptation of Thermal Concept

▪ First Approach for New Power Ranges

▪ Revision of Specification needed (Reformer)

▪ Initiation of new Work Package System Development


Next steps (Year 2)

WP 4.1

• System Concept development

WP 4.2

• Concept First order packaging

• Concept Second order packaging

WP 3.1

• Proof of modified Concept

• Concept adaptation to new power range

• Integration of reformer and PC into hot module

WP 3.2

• Validation of adapted concept

Thermal Management

System Development

NMWNTB


Next steps (Year 3 / 4)NMW

NTB

WP 3.1

• Transient simulation of thermal system

• Analyze system design for thermal stress

• Increase the level of detail in the thermal mode

Thermal Management

System Development

WP 4.1

• System Control definition

• System Design development

WP 4.2

• Manufacturing strategy development

• Build up a System Demonstrator


Questions ?

Simulation validated with Thermal Demonstrator.

Documents

Http:// WP 3: Thermal System Strictly Confidential 1 Workpackage 3: Thermal System Project Meeting, May 11, 2006