Phase Change Material Heat Accumulator for the HEXAFLY Hypersonic Glider

From the launchers to the spacecrafts, various on-board systems have to be maintained within specified temperature limits. Phase Change Materials (PCM) offer the possibility to store thermal energy directly as latent heat of fusion. Among the advantages of a PCM device are the stability of temperature control, the absence of moving parts and a reduced mass. The HEXAFLY-INTERNATIONAL project aims to flight test an experimental vehicle above Mach 7 to verify its potential for a high aerodynamic efficiency during a free-flight. European Major Resarch Centers and Industries are collaborating on this challenge. The presented activity focus on the use of a Phase Change Material device already developed under ESA projects up to TRL 6. Two efficient heat accumulators using PCM will allow avoiding overheating of electronic units such as telemetry & telecommand receivers, transmitters and data acquisition units for the hypersonic flight. The paper presents the complete cycle of design and environmental testing for the two PCM Heat Accumulators selected for the flight. The conclusions will show the benefit of adopting a Phase Change Material Heat Accumulator.