Analysis of liquid hydrogen power systems for near space unmanned aerial vehicles

Abstract

For near space unmanned aerial vehicles(NSUAVs), efficient power type is the key to support their long flights. It is considered that the "airborne liquid hydrogen storage + hydrogen fuel cell" scheme is in line with the trend of NSUAVs' greater endurance and larger payloads. In allusion to this scheme, the technology status of hydrogen supply processes, airborne hydrogen tanks, air supply processes and water/heat management for fuel cells are summarized in this paper. Technical analysis and summaries are carried out on hydrogen delivery methods, structures and materials of airborne hydrogen tanks, as well as the influences of low pressure environment on the suction performance of air compressors and heat dissipation performance of fuel cells. The development direction of relevant technologies is also discussed, providing reference for later studies.

Keywords

• near space
• unmanned aerial vehicles
• liquid hydrogen
• hydrogen supply process
• hydrogen tank
• hydrogen fuel cell