著者

江口 譲 杉本 聡一郎 服部 康男 平口 博丸

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.81, no.823, pp.14-00478-14-00478, 2015 (Released:2015-03-25)

参考文献数

15

被引用文献数

1

---

Explanation is given about a rational method to evaluate tornado-borne missile speed, flight distance and flight height to be used for safety design of a nuclear power plant. In the method, the authors employed Fujita's DBT-77 model as a tornado wind model to take the near-ground tornado wind profile into account. A liftoff model of an object on the ground was developed by conservatively modeling the lift force due to ground effect. The wind field model and the liftoff model have been compiled together with a conventional flight model into a computer code, named TONBOS. In this study, especially, the code is verified for one- and two-dimensional free-fall problems as well as a case of 1957 Dallas tornado wind field model, whose solutions are theoretically or numerically known. Finally, the code is validated by typical car behaviors characterized by tornado wind speeds of the enhanced Fujita scale, as well as by an actual event where a truck was blown away by a tornado which struck a part of the town of Saroma, Hokkaido in November, 2006.

著者

江口 譲 杉本 聡一郎 服部 康男 平口 博丸

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

pp.14-00478, (Released:2015-02-04)

参考文献数

15

被引用文献数

1

---

Explanation is given about a rational method to evaluate tornado-borne missile speed, flight distance and flight height to be used for safety design of a nuclear power plant. In the method, the authors employed Fujita's DBT-77 model as a tornado wind model to take the near-ground tornado wind profile into account. A liftoff model of an object on the ground was developed by conservatively modeling the lift force due to ground effect. The wind field model and the liftoff model have been compiled together with a conventional flight model into a computer code, named TONBOS. In this study, especially, the code is verified for one- and two-dimensional free-fall problems as well as a case of 1957 Dallas tornado wind field model, whose solutions are theoretically or numerically known. Finally, the code is validated by typical car behaviors characterized by tornado wind speeds of the enhanced Fujita scale, as well as by an actual event where a truck was blown away by a tornado which struck a part of the town of Saroma, Hokkaido in November, 2006.

著者

須藤 仁 服部 康男 中尾 圭佑

出版者

一般社団法人 日本風工学会

雑誌

風工学シンポジウム論文集 第23回 風工学シンポジウム論文集

巻号頁・発行日

pp.469, 2014 (Released:2015-03-10)

---

空間的に発達する乱流をLESで計算するための流入境界条件の設定方法として,リニアフォーシングに着目し,リニアフォーシングにおいて乱流長さスケールを規定する方法を考案した.等方乱流を対象としたLESの結果から,本リニアフォーシング法のLESへの適用性,乱流長さスケールを規定する方法の有効性を評価した.その結果,全散逸率に対するサブグリッドスケール散逸率の比が0.6より小さくなる格子条件下において,リニアフォーシングで生成されるべき等方乱流の基本的な性質を再現できた.また,本リニアフォーシング法で導入される時間平均長さの設定により,パワースペクトルの低波数域を変化させ,乱流の長さスケールを調整できることが示された.