2024 Volume 44 Issue 169 Pages 19-22
The background oriented schlieren (BOS) technique can measure the pressure field of a measurement target by using only a background image and a camera, thus can easily achieve non-contact visualization and quantitative measurement. Based on our previous studies, we introduced three applications of the BOS: visualization of transparent objects in fluid, visualization of exhaled breath, and pressure field measurement of underwater shock waves. BOS can visualize objects with small density differences (exhaled breath) by increasing the measurement sensitivity through increasing the distance between the object and the background image. For pressure field measurement, we proposed a BOS with a novel constructed 3D reconstruction, i.e. VT-BOS. VT-BOS has a accuracy that is nearly independent of spatial resolution and a computational cost of 1/10,000 of conventional BOS. In the future, VT-BOS can be expected to a pressure field measurement method in substitute of contact measurement methods such as hydrophone.
