Thermal and Energy Management for Hypersonic Cruise Vehicles - Cycle Analysis

© 2015, AIAA American Institute of Aeronautics and Astronautics. All rights reserved. In the frame of the HIKARI project (European 7th Framework Program) dealing with the preliminary design of subsystems for high-speed civilian transport airplanes, potential energy/thermal management cycles are investigated. These aircraft are exposed to very high heat fluxes both on the external surfaces of fuselage and wings as from the inside of the propulsion system. Hence, the management of the thermal condition for the overall system is key as it needs to provide the necessary cooling both for the passenger cabin as for the various on-board equipment. Likewise, these high thermal fluxes, if managed correctly, can also cover the on-board energy needs. In order to assess this thermal and energy management, some thermodynamic cycle studies have been undertaken with the software EcosimPro/ESPSS. Different approaches have been considered on several Mach 5 and Mach 8 concepts. Whatever the concept, it is possible to find a thermodynamic cycle able to cool both the airframe and the on-board equipment as well as to provide the on-board power demands throughout the flight. This highlights that a thermodynamic cycle definition is feasible for a given trajectory. However, when performing a preliminary sizing of the cycle components, elements such as turbomachinery, heat exchangers and tubing can be large and heavy. Hence, the design optimization of a on-board thermal-energy cycle would require a coupling of the thermodynamic cycle analysis with the mass and sizing of the different cycle elements in combination with a trajectory optimization.