Laser Ignition of Large Scale Combustion Air Heaters

The AEDC Aero Propulsion Test Unit (APTU) facility completed successful operation at Mach 6 and Mach 7 direct connect tunnel conditions utilizing a prototype Mach 5 free-jet configured Combustion Air Heater (CAH) injection system developed by CFD Research Corporation. These results and upgrades proposed here were presented at the 2018 Hypersonic Technology & Systems Conference. This effort will fully leverage prior SBIR deliverables to further improve test section flow quality throughout the entire APTU Mach 3-7 free-jet or direct connect tunnel operational range. The following efforts will be completed in order to achieve TRL 9 operational status of swirl stabilized CAH injection system technology within future APTU test operations: 1. Optimization of swirl stabilized injection within all APTU tunnel (Mach 3-7) configurations; 2. Upgrade of the isobutane simplex injection system to maximize atomization performance and minimize discharge temperature spread; 3. Demonstration within nominal APTU test operations; 4. Optimization of APTU operational protocols; and 5. High fidelity facility simulation demonstration. Follow-on transfer of this comprehensive APTU facility modeling and simulation approach to the APTU customer base will facilitate improved test article instrumentation implementation, extend test event run times and increase data acquisition and reduction fidelity.