INVESTIGATION OF AIRFLOW FOR NATURAL VENTILATION IN THE TYPICAL MEDIUM-RISE HOUSING CLUSTER IN SOUTHEASTERN NIGERIA

Abstract

Wind-driven natural ventilation depends on the microclimatic conditions of its environment. In urban streets, it is affected by the ambient wind flow and air temperatures. In this study, field experiments were carried out in selected streets of a typical medium-rise housing cluster in southeastern Nigeria. The study aimed to understand the characteristics of air flow within this housing category, and to better evaluate the potential of natural wind-driven ventilation in this class of settlement. Wind speed and directions in the middle of selected streets were measured continuously. In parallel, the undisturbed climatic conditions above the street canyon were recorded as well. The general conclusion is that inside the streets, the potential of natural ventilation for both single and multi-branch type configurations is reduced, while that of continuous street configuration (without intermediate intersections) provided a higher potential for natural wind-driven ventilation. This is mainly due to the internal interference and reduction of wind speeds inside the street canyons. Generally, universal meteorological information gotten from unobstructed areas in cities are used in the design of buildings; thus, the significance of this study outlines the importance of obtaining microclimatic information in pre-design stages.