BRIST – fuel cell, integration and system test

It has simultaneously been shown that, besides power, the working principle of the fuel cell is suitable for further uses on board. The water produced can be fed into the service water reservoir; the used low-oxygen air can be deployed to reduce the oxygen level in fuel tanks or in the cargo hold (inertisation); and waste heat can be used to avoid the build-up of ice.

The project consortium comprised, on the one hand, of companies that each are leaders in their respective fields. On the other hand, research institutions were also involved, which not only helped to raise understanding of the technology itself, but also to create new impulses, methods and ideas. The course of the project confirmed the correctness of this approach as it was repeatedly the case that original methods and approaches needed to be adapted. The high complexity of a multifunctional system is attributable to the fact the requirements are contradictory, in part. For example, a high level of surplus air (stoichiometry) is advantageous for specification-compliant electrical performance and dynamics, while for the aforementioned inertisation function a low level of air is beneficial as only in this way can the oxygen content in the respective areas be significantly reduced.

In order to gain both experience with the behaviour of such systems and also be in the position to test components, the Fuel Cell Test Centre (FCTC) was established in Hamburg. Besides the flexibility of integrating new components, e.g. water separators from AOA or power electronics from EADS-IW, the system behaviour under flight conditions was to be tested. The tank simulator was designed in such a way that the pressure conditions of an aircraft tank at cruising altitude could be replicated using a vacuum pump. Laboratory tests showed reactions between the fuel cell and the fuel tank inerting system (FTIS), which could, however, be minimised through a more suitable design of the overall system. By the end of the project, a laboratory setup was in operation that could independently reproduce the relevant aspects of a flight and thereby simulate the intended operations in an aircraft.

The BRIST project delivered new insights to all involved parties and developed knowledge for the deployment of fuel cell systems in aircraft. This has put the project partners in the position to advance industrialisation and develop new products. Future market introduction will bring about new jobs and the advancement of technology will strengthen the market position.