COOLING SYSTEM FOR LIQUID HYDROGEN UAVS OPERATING IN HIGH-TEMPERATURE ENVIRONMENTS

In the Phase I effort, we are developing a cooling system that integrated into the fuselage of the NEOEx liquid hydrogen fueled Group 2 UAS aircraft. We will investigate using the cooling capacity of the liquid hydrogen stored on-board the aircraft as fuel. The liquid hydrogen requires a heat source to raise the temperature from 25 K saturated vapor to ambient temperature (290 K) prior to being consumed in the fuel cell to make electric power. The fuselage and the external environment would provide the heat source. The design will incorporate cooling of the fuel cell itself as well as any electrical components inside the fuselage for aircraft operations or payloads such as camera boards. Successful testing with liquid hydrogen of the newly designed cooling system inside the aircraft fuselage will enable a Phase II flight demonstration of the system in Arizona with the Arizona State Department of Forestry and Fire Management.The specific technical objectives of the Phase I research effort are as follows:1. Investigate use of cryogenic cooling capacity of liquid hydrogen.2. Design an integrated cooling system that increases the operating temperature of the unmanned aerial vehicle.3. Design a fuselage that will allow increased cooling effects as well as fit the cooling system on-board the aircraft.4. Investigate aircraft performance impact with new cooling system on-board the aircraft.5. Conduct ground tests of the system with cryogenic fluids.