擬似粒子追跡法を用いた三次元流場の計測に関する研究

Abstract

A lot of PIV (Particle Image Velocimetry) techniques are proposed to obtain three-dimensional vectors in three-dimensional regions.Generally, in the single aspect PIV method, it is difficult to measure the particle position of the sightline direction in high accuracy. Then, the ideas of the spatial filter were combined with the laser sheet and acquire flow velocity in the sightline direction in handily and high accuracy. The sampling speed of images is related to the accuracy of measurement in this method. In this paper, a new technique is proposed to measure the three-dimensional flow velocities using multi-laser sheets. Particles are tracked as the quasi-particles in the three- dimensional positions. As the each three laser-sheets are prepared to assign positional information of sightline direction, three-dimensional vectors are obtained on multiple sections. Uniform Flow fields are measured to calibrate this method and 3% precision limit is obtained. The nominal-wake of the model-scale ship is measured and compared the velocity distribution with previous 5-hole pitot probe data. Good agreement is obtained between them.