Installation, instrumentation and testing of an exhaust gas heat recuperator for hybrid cycle

This report presents the work done in the frame of a Minor in Energy project in the school of Mechanical Engineering at the Swiss Institute of Technology of Lausanne (EPFL), in order to obtain 10 ECTS credits. It is to install, instrument and test an exhaust gas heat recuperator and to assess its performances. The project fits into the topic of hybrid cycles based on fuel cells and inverted Brayton-Joule cycles. The system is first presented and the instrumentation is detailed. The tests are then described and the results are presented and discussed. The heat exchanger appears to be very large versus the gas flowrate and the flue gases are cooled down to low temperatures. The condensation is an issue and the condensed water collection system is not efficient, leading to problems in doing power estimations. Finally some possible improvements of the system are proposed and described. A smaller heat exchanger is also computed and presented as an example.