Potential of cross-ventilation channels in an ideal typical apartment building predicted by CFD and multi-zone airflow model

Abstract

Natural ventilation is a passive environmental technology which can improve indoor air quality and cool down the building without consuming energy. However, due to the increasing densities of cities, land prices are constantly increasing. To save building area, apartment houses often use one elevator hall for multiple households (i.e. three-, four-, six-, or eight-households). But when an apartment is on the leeward side, the wind pressure ventilation is low. Therefore, this study proposes establishing a horizontal airflow channel—cross-ventilation channel—in the elevator hall to improve air exchange rate. The paper aim to predict its effect. Computational fluid dynamics (CFD) simulation verified by wind tunnel test, and the multi-zone airflow model are applied to predict the air flow rates in seven cities in China, which represented the five climate zones of China. It is found that the horizontal airflow channel can obviously improve the ventilation capacity of the leeward apartment, especially for south-side apartment. The area ratio of channel-to-ground increases by 1%, and the ventilation rate increases by average 5% in this study. It could be used as an alternative technology for improving natural ventilation in apartment buildings.