Oxidation Resistant Heating Elements for High Temperature Wind Tunnels

ABSTRACT: High temperature wind tunnels are needed to replicate the environment vehicles will experience during high Mach Number flight. Of particular interest are sustained airflow temperatures of 2800„aF. To obtain this temperature, improved heating elements and systems are needed. During Phase I, an oxidation resistant, high temperature iridium-based wind tunnel heating element has been developed. Resistive heating experiments showed element surface temperatures greater than 1650„aC (3000„aF) can be obtained with the current architecture. During Phase II, the process parameters and techniques developed in the Phase I effort will be optimized. For the Phase II investigation, Plasma Processes will partner with the University of Alabama at Huntsville to aid in the design and analysis of a complete heating element system and Southern Research Institute to characterize the heating element properties. The modular system will then be delivered to the Air Force for testing with high mass flow rates at Arnold Engineering Development Center. BENEFIT: The development of an oxidation resistant heating element and heating element system will enable testing of engines and critical hypersonic components such as leading edges and nose tips at high Mach Number (5+). This capability will support numerous military applications with in the Department of Defense and other government agencies such as NASA. In addition, this technology is needed for commercial entities in the following sectors: oxidation resistant coatings, defense, material R&D, nuclear power, aerospace, propulsion, automotive, electronics, crystal growth, and medical. Targeted commercial applications include net-shape fabrication of refractory and platinum group metals for rocket nozzles, crucibles, heat pipes, and propulsion subcomponents; and advanced coating systems for x-ray targets, sputtering targets, turbines, rocket engines, and furnace and heater components.