Non-intrusive Water Surface Velocity Measurement Using Spatial Cross Correlation Technique

Abstract

The limitation with the method of calculating surface water velocity is the direct contact of the velocity measurement tool to the flowing water which results in the mechanical wear and high maintenance cost. This paper describes the flow visualization and surface water velocity measurement technique using the non-intrusive method. This system gives the instantaneous results and is reliable, flexible method which can be applied successfully in many engineering applications. It is a distension of a video imaging technique to measure the velocity using the pattern matching method. The system was indigenously developed with the help of CMOS camera and paper particles which were used as the tracer particles. If video is taken from far distance then ortho-rectification is applied to calculate accurate results. Video was recorded at Bombay airport model, CWPRS, Pune under different environmental conditions. The code is written in MATLAB which includes segmentation, pattern matching and post processing steps.