Measurements of Micro Backward Facing Step Flows with a Single Camera Micro 3D-PTV

Abstract

A micro 3D-PTV system is constructed using single camera system. Two viewing holes have been installed just behind the object lens of the microscopic system to construct a stereoscopic viewing. The system consists of one high-definition camera (1028 x 1024 pixel, 500fps), an Ar-ion laser, a plate of two-viewing holes and the host computer. A hybrid genetic algorithm (GA) has been used to find out the same image pairs. In the genetic algorithm, crossover operation, mutation operation and reproduction operation were introduced while changing the percentile values of these three values for finding the most optimal pairing conditions. An epipolar concept has been adopted to eliminate spurious candidates that cannot be regarded as the same particle pairs. The measurement errors in camera calibration for X, Y and Z coordinates were 0.083μm, 0.045μm and 0.083μm, respectively. The constructed measurement system has been used for measuring a micro backward facing step channel (H x h x W: 36μm x 70μm x 3000μm). Reynolds