Abstract: A new regulatory guide has been issued by the Nuclear Regulation Authority of Japan since the last year. According to this guide, electric power companies have to assess the influence of tornadoes on their nuclear power plants for operation. The purpose of this study is to evaluate the likelihood of the occurrence of F3 tornadoes, which are the largest encountered in Japan, and to consider the possibility of the regionalization of the maximum wind speed. Then, mesoscale analysis with a numeri...
英字タイトル:
A study on the regionalization of tornadogenesis for the domestic largest scale of tornado

Abstract: Most of Japanese tornados have been reported near the coast line, where all of Japanese nuclear power plants are located. It is necessary for Japanese electric power companies to assess tornado risks on the plants according to a new regulation in 2013. The new regulatory guide exemplifies a tornado hazard model, which cannot consider the variation of tornado intensity along the path length and consequently produces conservative risk estimates. The guide also recommends the long narrow strip a...
英字タイトル:
Tornado hazard model with the variation effects of tornado intensity along the path length

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...
英字タイトル:
Problems and proposed solution in evaluating tornado-borne missile speed