飛散物の動的空力特性の直接計測システムの試作

Abstract

Damages to houses in strong wind, e.g. typhoon or tornado, are caused by flying debrisin most cases. The configuration of flying debris such as branches of tree, pebbles, piecesof broken structures and so on is categorized as a "bluff body". Therefore, prediction offlying motion of bluff body is important to evaluate the impact of flying debris for thewind resistant design of claddings and the reduction of damage to houses.This study aims to develop a system to measure the motion of bluff body and to clarifyaerodynamic characteristics of flying debris. Some units of micro-computer, three axisaccelerometer, pressure sensors, A/D converter, Wi-Fi adaptor and small battery wereassembled as a stand-alone probe to measure the motions and wind forces on a flyingbody. The measuring probe was built in a rectangular shaped test body. The test body wasdropped in a test region with no wind. The pressure and the acceleration on the test bodywere measured, while capturing the motion of the body by taking movies with videocameras and conducting image analysis.