Velocity and size measurement of falling particles with fuzzy PTV

Abstract This paper describes a method for simultaneously measuring the velocities and sizes of falling particles. The measurement method consists of two parts. One is the recognition of the particles from a raw image by an image-processing technique in order to obtain the sizes and positions of the particles, and the other is a measurement technique of Particle Tracking Velocimetry based on fuzzy logic for the falling velocities of particles. The method is examined by a numerical experiment with computer-generated images. The result shows that the present method can be applied on-line for real-time processing of practical measurements.