鉛直ダクト内の気申分散粒子輸送: 第3報——粗大粒子輸送の可視化実験とLagrangeモデルによる達成解析

摘要

To prevent the contamination of paniculate matter in indoor environments, a control of the transmission of particles from outdoors to indoors through ventilators is important. To this end, the overarching objective of this study is to develop a passive method for reducing the amount of entrained particles through the ventilation system. In this research, we focused on a simple vertical ventilation duct and reported the analytical results of particle transportation inside a vertical duct under various boundary conditions.rnIn this study (Part 3), a visualization measurement of the large particle movement inside the vertical duct was conducted and the path lines of large particles were shown. Furthermore, Computational Fluid Dynamic (CFD) simulation with a Lagrangian particle tracking approach was also conducted by considering the particle-air interactions; one way coupling and two way coupling approaches. A difference in the prediction results in particle dispersion fields and particle retaining fraction were confirmed by the one way- and two way coupling approaches.%本研究は，住宅用の鉛直ダクトを対象として，導入外気中に含まれる気申分散粒子系汚染物質の輸送現象を実験，数値解析により明らかにするもので，既報（第1報）ならびに（第2報）ではPIVによる流れ場計測結見CFDの流れ場予測精度の検証，粒径1μmから100μmの微粒子を対象としたLagrangeモデルによるParticle Trackingの実施と鉛直ダクト内の粒系別通過率の解析結果を報告している．本報（第3報）では目視可能な粒径サイズであるミリメータ（mm）スケールの模擬粒子を対象として，鉛直ダクト内での輸送現象を可視化すると共に，実験と対応する条件で数値解析を実施した結果を報告する．