Using Large Scale Particle Image Velocimetry with Unmanned Aerial Vehicle to Measure Surface Flow Fields

Large Scale Particle Image Velocimetry (LSPIV) is a nonintrusive measurement technology. It requires fewer operators and less time than other intrusive methods. While using the LSPIV methods to measure surface flow fields, a camera is usually installed on a fixed position of river sides to record the flow conditions. However, it leads to image distortion and error of image processing. This study attempts to apply an unmanned aerial vehicle (UAV) with a camera to record the images of the water surface. It is expected to improve the orthogonality of the recording images. The tracing particles of image velocimetry used the ripples and foams on the water surface. Then, the LSPIV was used to analyze the spatially information of flow fields. The results showed the flow velocities determined by the LSPIV was close to the velocities measured by the velocimetry. It was showed that using LSPIV with UAV to measure water surface flow fields is a feasible, accurate and safe flow measuring method. It is expected to apply in future study, such as habitat survey and hydraulic characteristic.