ミストスプレイを用いた火山灰除去装置の開発

（２）：数値流体計算を用いた火山灰の運動とスプレイによる除去率の評価

抄録

The aim of this study is to understand the precise cross sections of collision processes between spray water drop and volcanic ash and also investigate the validity of water spray for the ash removal. We reproduce the accurate cross sections by considering six major collision processes and carried out a simple two-dimensional simulation for roughly estimating the survival rate of volcanic ashes. Firstly, we confirmed that the effective cross section is almost identical to two hard sphere core collisions if the size of volcanic ash is larger than 10μm. Secondly, we found that the ash removal via water spray shows remarkable high efficiency, i.e. the removal rates are more than 80%. The simulation will be further more improved and enabled to compare with mockup-tests of a new volcanic ash removal system which has currently been developed by TEPCO.