Test Results for a 20 kW Two-Phase Pumped Cooling System with and without Accumulator

In the EU funded BRAVA project, technologies for a Fuel Cell based Power Generation System for aviation are being developed. One of these technologies is the cooling system for the fuel cells. In this paper, the test results for a demonstrator for a novel two-phase pumped cooling system with 20 kW cooling capacity are presented. This system uses the evaporation of liquid methanol to remove waste heat from the heat sources. Several concepts have been tested with this demonstrator, including the ‘no accumulator’ concept. This concept offers a large mass reduction compared to a conventional system with accumulator, not only because of the absent mass of the accumulator, but also because the amount of fluid in the system is much smaller. This paper also discusses the applicability of the concept to space application, e.g. the use of ammonia instead of methanol, and the microgravity environment.