竜巻飛来物速度評価法の課題とその解決策
Problems and proposed solution in evaluating tornado-borne missile speed
著者:
江口 譲 Yuzuru EGUCHI 杉本 聡一郎 Soichiro SUGIMOTO 服部 康男 Yasuo HATTORI 平口 博丸 Hiromaru HIRAKUCHI
発刊日:
公開日:
Design speedFujita modelLiftoffNumerical simulationStandardTornado missile
概要
Abstract: Large variation was found among the design values of tornado missile speed shown in current stan dards and guides in Japan and U.S. It was also found that the design missile speed indicated in the Guide issued by the Nuclear Regulation Authority of Japan is the most restrictive among them. The primary reason is due to the evaluation method where all the objects are unconditionally assumed to be placed in air as gh as 40 m, even if the object should be on the ground. In order to solve this problem, the authors have a dopted the tornado engineering model DBT-77 proposed by Dr.Fujita as a wind field model, and developed a n umerical analysis code TONBOS with adding an object liftoff model. The effectiveness of the numerical anal ysis code was demonstrated by simulating liftoff and flight of a truck struck by an F3 tornado in Saroma.
