静穏環境下における立位人体周囲の汚染質濃度分布に関するCFD解析 : 数値サーマルマネキンに関する研究 (その2)

抄録

The rising stream around a human body due to metabolic heat can carry contaminants from the floor level to the human breathing region. Thus, the quality of the breathing air greatly depends on the concentration distribution in the lower part of the room and the characteristics of the local air motion around the body. In this paper, a modeled human body (Computational Thermal Manikin) is placed in a room, which is air-conditioned with a displacement ventilation system. Flow and temperature fields around the manikin are analyzed by CFD (Computational Fluid Dynamics) using a low-Reynolds-number type k-ε model. Based on the predicted flow field, the age of supply air and the residual life time of air in the room are also numerically calculated. Three cases on prediction of the contaminant concentration distribution are carried out under different positions of contaminant generation. The quality of the breathing air is assessed, using the newly defined index, indicating the effective entrainment ratio of the lower region air to the breathing air. The CFD analysis results agree well with previous experimental data.