The results of the application of an exergy-based method to highly dynamic, integrated hypersonic vehicle concepts are presented. Conventional aircraft systems and sub-systems traditionally are designed relying heavily on rules of thumb, individual experience, and rather simple, non-integrated tradeoff analyses, which are highly dependent on the evolutionary nature of vehicle development. In contrast, hypersonic vehicles may contain new sub-systems and revolutionary concepts for which there is no existing database to support an evolutionary synthesis/design approach. Thus, a simple tradeoff analysis becomes virtually impossible, particularly in light of the highly integrated, non-linear relationship between hypersonic vehicle sub-systems and the complexity of the missions involved. Therefore, the departure from existing databases and experience levels requires an integrated approach and a common metric for the synthesis/design of hypersonic vehicles to achieve an optimal synthesis/design. To that end, an exergy-based mission integrated methodology is introduced and compared to traditional measures (including a non-integrated approach) by applying these to the synthesis/design and operational optimization of a hypersonic vehicle configuration comprised of an airframe and a propulsion sub-system (consisting of inlet, combustor, and nozzle components). Results of these optimizations are presented and include a quantification of all vehicle losses in terms of exergy lost or destroyed, providing a common metric for the vehicle designer to identify where the largest improvements in vehicle performance can be made. Furthermore, via a number of parametric studies, the impacts of the design and operational decision variables on exergy destruction are discussed.
Numerical analysis and experimental research of the rubber boot of the joint drive vehicle