101110 CRECOS-Concept selection tool for evaluation of thermal insulation concepts

Case example: Concept selection tool for evaluation of thermal insulation concepts Pauli Salminen Department of Engineering Design and Production

Thermal insulation is important for Solid Oxide Fuel Cell systems working at ~800 °C

Stack module

BoP module

• Experimental unit: Size is comparable to passenger car

Thermal insulation is thought to be simple and boring design task… … but it affects to other subsystems and properties in the test unit!

– – – –

System layout Support of components Actuators Instrumentation

And finally it has a great effect on total electrical efficiency of the system!

Four insulation concepts were created

Selection tool systematically analyzes concepts and provides documentation Initial Data

Requirement prioritization

Weightings

Scorings 2

RESULTS+ANALYSIS

24 requirements were chosen for evaluation process • Quantative requirements: – Insulation efficiency – Low insulation surface area – …

• Subjective evaluation of requirements : – Component layout freedom – Serviceability of components – …

Evaluation chart

Three things are critical for results: 1. Selecting requirements

• Group work • Requirements should be given as a positive manner

Three things are critical for results 2. Prioritization matrix and Weightings

Binary evaluation matrix (Paired comparison) +Easy to make +Simple -Binary evaluation is rough -Does not provide much information Analytical Hierarchy Process (AHP) would provide benefits

Three things are critical for results: 3. Evaluation (scoring)

• Group work • Scale!

• Statistical tools?

RANK

Analysis of results is shown in charts

• Visual charts are better than numbers

Conclusions • Concept selection tool supports radical innovations which could otherwise be judged as silly or naive • This tool gives satisfactory results, but could be improved by implementing techniques like Analytical Hierarchy Process

Thank you!