High-Repetition-Rate, Narrow-Linewidth Burst-Mode Optical Parametric Oscillator for High-Speed Flow and Combustion Diagnostics

NASAnbsp;aero-science ground test facilities, including transonic, supersonic and hypersonic wind tunnels,nbsp;provide critical data and fundamental insight required to understand complex phenomena and support the advancement of computational tools for modeling and simulation.nbsp;In these facilities, real-time, high-repetition-rate (10 kHzndash;1 MHz) 2D or 3D measurement techniques are needed to track the high-speed turbulence dynamics.nbsp;nbsp;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.nbsp;This proposalnbsp;offers an integrated package of truly cutting-edge,nbsp;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.nbsp;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.)nbsp;in realistic tunnel conditions. The proposed high-repetition-rate OPO-based LIF technique which is suitable for 2D and 3D multi-parameter measurements is a state-of-the-art technique for analysis of unsteady and turbulent flows.nbsp;