NASA aero-science ground test facilities, including transonic, supersonic and hypersonic wind tunnels, provide critical data and fundamental insight required to understand complex phenomena and support the advancement of computational tools for modeling and simulation.In these facilities, real-time, high-repetition-rate (10 kHz–1 MHz) 2D or 3D measurement techniques are needed to track the high-speed turbulence dynamics. Current state-of-the-art measurement capabilities in harsh wind tunnelenvironments are effective but limited to sample rates of 10 hertz, which is insufficient to track the dynamic of the turbulent reacting and non-reacting flows. This proposal offers an integrated package of truly cutting-edge, high-repetition-rate (up to 1 MHz rate), narrow-linewidth, burst-mode Optical Parametric Oscillator (OPO) system for multi-species laser induced fluorescence (LIF) detection in NASA ground test facilities.The concepts and ideas proposed are ranging from proof-of-principles demonstration of novel methodologies using a pulse-burst laser pumped OPO system for multi-parameter measurements (density, temperature, species concentration, and flow visualization, etc.) in realistic tunnel conditions. The proposed high-repetition-rate OPO-based LIF technique which is suitable for 2D and 3D measurements is a state-of-the-art technique for analysis of unsteady and turbulent flows.
The proposed high-speed OPO-based LIF technique is suitable for most wind tunnel facilities for multi-parameter flow measurements, including NASA 31” Mach 10 facility, 20” Mach 6 facility, 15” Mach 6 facility, 8 foot high temperature tunnel, Arc Heated Scramjet Test Facility (AHSTF), National Transonic Facility (NTF), 0.3-meter Transonic Cryogenic Tunnel (TCT), and NASA HYPULSE Mach 5-25 Shock Tunnel.
High-speed OPO system could be widely applied in many R&D areas, such as gas turbine engines, hypersonic scramjets, hypersonic vehicles, aerospace capsules, and unmanned flights which are important to national security and defense. The other potential market includes industrial aeronautical companies, such as Boeing, Lockheed Martin, GE, Pratt-Whitney, and other industrial aerospace interests.