Thermal Analysis of Hypersonic Inlet Flow with Exergy-Based Design Methods

Abstract

This paper presents results of work that has been done in developing use of the Second Law of Thermodynamics and methods such as exergy and thermoeconomics into a system-level analysis and design methodology. The application of these methods to the design of a complete flight vehicle is illustrated by considering an integrated airframe/propulsion system as a device to do work. This shows how system-level consideration of exergy applies to all vehicle systems in consistent terms. For the hypersonic inlet flow problem, it is shown that a thermal energy exchange with the inlet flow could be used to position the inlet shock in the optimum shock-on-lip position for off-nominal flight conditions. The thermal heat exchange analysis has been done for a full range of Mach numbers both higher and lower than nominal. It is shown that there is a potential benefit in terms of reduced exergy destroyed using thermal energy addition than by the shock at higher Mach numbers. The paper then discusses how a device to accomplish this result would have to be integrated into a complete vehicle design.

Keywords

• exergy analysis, thermoeconomics, 2nd Law of Thermodynamics, hypersonic aircraft/vehicles, shock-on-lip positioning, MHD shock control