High-resolution PIV for characterization of the inflow to a cavity flameholder

A methodology for the implementation of high-resolution, two-component, two-dimensional particle image velocimetry (PIV) in a high-speed, high-enthalpy flow is presented and demonstrated. The objective is to resolve the finer scales of combusting flows at high subsonic Mach numbers for accurate boundary conditions quantification for direct numerical simulations. A three-pronged approach consists of finding a near-optimum setup specific to the experiment, enhancing the raw signal with a novel filter for high-speed flows based on a logarithmic transform, and quantifying uncertainties. The methodology effectiveness is demonstrated with synthetic PIV, real PIV, and comparison with numerical simulations.