APPLICATION OF 2D NUMERICAL FILTER FOR VELOCITY MEASUREMENT TECHNIQUE IN THE FLOW FIELD OF OCEAN MODELS

摘要

As a important velocity measurement technique, PTV is often used in ocean model experiment. PTV (Particle Tracking Velocimetry) is a non-intrusive optical flow measurement technique which supplies real-time velocity sample throughout 2D plane of the flow field. Using a numerical camera PTV get track of the tracer, some small, buoyant particles, which is scattered throughout the flow area. Analyzing each two consecutive images and performing a serials calculation, the velocity of the flow could be get. In this paper, the 2D numerical filter is applied to process data of PTV flow measurement. The 2D numerical filter permits the low frequency signal and damps or weaken the high ones, so the error flow data is corrected. Taking the example of physical model of Cangzhou Port, it is analyzed that the effect of applying Fourier Transform to PTV flow area. Finally, a set of system is proposed, including 2D numeric filtering and GIS flow area display, to process data automatically and continuously.