WIND VELOCITY FIELD ESTIMATION BY RAINDROP TRACKING USING PTV TECHNOLOGY

- DEVELOPMENT OF RAINDROP TRACKING METHOD IN REAL ENVIROMENT-

Abstract

Wind velocity field measurements around buildings are essential for wind-resistant design and wind risk evaluation of buildings. However, current technology to measure wind velocity field around buildings are limited in senses that either it is hard to measure wind speeds at multiple locations simultaneously or wind speed near surface with high resolution. To overcome these difficulties, the group by authors has developed a methodology for wind field estimation based on raindrop tracking using PTV technology. This summary reports the way we conduct raindrop tracking, i.e. steps and measurement jigs. The core idea is, fixing two cameras on a rigid jig, to obtain photos that target calibration board on ground. Then, in actual raindrop tracking, the rigid jig with two cameras is tilted up to target the volume where raindrops are tracked; i.e., wind velocity field is measured. The jigs for this were developed, and it was confirmed in our test laboratory that the images required for PTV analysis can be obtained.