Using System Simulation to Manage Increasing Thermal Loads on Aircraft Fuel Systems

Today's modern military fighter jets are like “a flying thermos bottle” according to Steve Iden, AFRL Invent Program Manager ^[1]. Many engineers have been saddled with trying to put the thermal loading constraints of these fighter jets on ice. This places increasing demands on utilizing the fuel system as a heat sink to dissipate thermal loads coming from onboard electronics, oil and hydraulic systems, avionics bay cooling, and weapons modules. Engineers today are looking to simulation to help tackle these design challenges, and they have more power than ever with simulating fuel systems to evaluate feasible system designs with given requirements on thermal power loading, fuel capacity, and tank geometry. With a given set of key performance metrics and limits on a design, the design space can be quickly explored to find optimum metrics such as flight mission duration or required component sizing to meet thermal load requirements.