Cakir B.O., Lavagnoli S., Saracoglu B.H. & Fureby C.; 2024, “Sensitivity and Resolution Response of Optical Flow based Background Oriented Schlieren to Speckle Patterns”, Meas. Sci. Tech., 35, 075201. doi: 10.1088/1361-6501/ad30bd.
Abstract: The degraded resolution and sensitivity characteristics of background-oriented schlieren (BOS) can be recovered by utilizing an optical flow (OF)-based image processing scheme. However, the background patterns conventionally employed in BOS setups suit the needs of the cross-correlation approach, whereas OF is based on a completely different mathematical background. Thus, in order to characterize the resolution and sensitivity response of OF-based BOS to the background generation configurations, a parametric study is performed. First, a synthetic assessment based on an analytical solution of a one-dimensional shock tube problem is conducted. Then, a numerical assessment utilizing direct numerical simulation data of density-driven turbulence is performed. Finally, the applicability of the documented conclusions in realistic scenarios
