Fuel Cell Thermal Management Concepts for Electrified Aircraft Propulsion

Advanced Cooling Technologies, Inc (ACT) proposes to develop a thermosyphon (i.e., passive two-phase heat transfer device) to extract and transfer the waste heat generated by the membranes in the hydrogen fuel cell stack and maintain the in-plane thermal gradients to ≤10 Δ ºC. The proposed thermosyphon has the following advantages: high thermal conductance, light weight, high reliability, easy to fabricate and can be easily integrated with the hydrogen fuel cell stack. In Phase I, ACT will perform a detailed trade study to design a thermosyphon that can extract the waste heat from the membranes. A variable conductance feature will be added to the thermosyphon in order to passively keep the membrane temperature near the optimal range (80°C) regardless of the heat rate amount and heat sink conditions. The proof-of-concept prototype will be fabricated and its thermal performance under different testing conditions and dielectric working fluids will be demonstrated in Phase I. During Phase II, the proposed thermal management system will be integrated with a small-scale fuel cell stack to test the stack thermally and electrically. By the end of the Phase I and II programs, the technology readiness level will mature to a TRL of 4 and 5, respectively.