Advanced thermal solutions provider Thermacore has announced that its heat pipe assembly recently completed testing at the NASA Ames Arc Jet Complex operating at very high temperatures in a hypersonic leading edge simulation, making it the first rigid embedded heat pipe module to operate successfully at those conditions.
The demonstration confirms that the embedded heat-pipe design is a reusable alternative to traditional consumable ablative heat shield materials employed on hypersonic leading edge applications, says the company.
“The recently completed testing demonstrates that the Thermacore wing leading edge module has achieved technology readiness level six (TRL 6),” John H. Rosenfeld, senior engineer at Thermacore, said. “This solution is now a real consideration for system and subsystem development for wings and engine inlets on hypersonic aircraft as well as thermal protection systems (TPS) for atmospheric entry, decent and landing of spacecraft.”
Developed in conjunction with the Lockheed Martin Company, the tested Thermacore module used six embedded heat pipes. Under independent tests, two units were operated in an arc jet plasma field at environments representing hypersonic conditions. The results were the same for both units; thereby, demonstrating repeatability and reliability of the thermal protection system.
The magnitude and capacity of the test at large sample sizes successfully simulated high-altitude atmospheric flight conditions — a capability that makes the Ames Arc Jet Complex unique. In the arc jet chamber, the Thermacore heat pipe assembly was exposed to gases heated and expanded to very high temperatures and supersonic/hypersonic speeds by a continuous electrical arc between two sets of electrodes. The gases—typically atmospheric air—pass through a nozzle aimed at the test sample in a vacuum. The flowing gases produce a reasonable approximation of the surface temperature and pressure and the gas enthalpy found in high velocity, supersonic flow—in this case, simulating high heat flux conditions at speeds from Mach 5 up to Mach 20.
Completing the Ames Arc Jet test regimen indicates the Thermacore module is ready for prototyping in an operational environment for spacecraft and hypersonic vehicles, according to the company. The arc jet data validates thermal models, heat shield design and performance characteristics.
