THE EFFECTS OF VARIOUS OPENING SIZES AND CONFIGURATIONS TO AIR FLOW DISPERSION AND VELOCITY IN CROSS-VENTILATED BUILDING

Abstract

The application of natural cross-ventilation in buildings located in the area where the wind speed is low is such a challenge. In hot and humid climate, sufficient air velocity is necessary in providing thermal comfort. Hence, this study intends to investigate the possibility of enhancing the indoor air velocity and flow distribution by employing the Venturi effect at the openings. Two research methods were applied namely field measurement and numerical simulation. The field measurement was executed at a single zone cross-ventilated building. Its purpose is to validate the numerical simulation steps and procedures. Meanwhile, investigations of the air velocity and flow distribution were conducted using ANSYS FLUENT CFD software. The findings indicate that the Venturi effect did occur at the openings. Providing a confined area at the inlet may enhance the Venturi effect, thus increasing the indoor air velocity. Based on the investigated scenario, it is found that the highest indoor air velocity of 0.2 m/s was achieved for the 75 % opening size with 1.5 m projection. This value indicated enhancement as the outdoor air velocity near the inlet was around 0.14 m/s only. The findings also indicate that the indoor air flow distribution of high air velocity focused more at the area of flow path between the inlet and outlet. The findings can be as guidance in enhancing the natural cross-ventilation in buildings especially that are located at the area where the wind speed is low. Nevertheless, the findings are limited to low-rise building with such opening configuration. Further study needs to be executed to determine the effects to other opening configurations and building heights.