Predicting Airflow in Naturally-ventilated Generic Houses

Abstract

This article reports the results of continuing research into the impact of the opening orientation andopening size on the natural ventilation of generic detached houses. The CFD simulation of 72 ventilation casesis generalized from actual houses surveyed in the suburban areas of Bangkok. It is discovered that largeropening in general allows higher indoor air velocities than smaller opening. In most cases, the Venturi effectproves to be efficient in terms of indoor air velocities up to approximately 1:1.5 proportion of inlet to outletopening area. In terms of air distribution, it is found that the opening size and the ratio of inlet to outlet openingarea do not have much impact on the uniformity in small square rooms. In large rectangular rooms, the Venturieffect improves the uniformity in two- and three-sided ventilation cases. In cross ventilation cases, however, theuniformity depends on the opening size. The results lead to the prediction of airflow and comfort which isdemonstrated by an example of application on an actual building.