The effect of the wind speed velocity on the stack pressure in medium-rise buildings in cold region of China

This paper presents the numerical simulation results of the stack effect in medium-rise buildings in Harbin, a typical city in the severe cold region of China. The simulation was carried out using the multizone ventilation model COMIS. The effect of the wind speed velocity and the temperature of the stairwell on the pressure difference curves shape have been investigated. The pressure difference between the stairwell and the outside shows a linear variation with the height. However, the wind speed velocity may have a strong effect on the pressure difference. The results of the simulation show that at high wind speed velocity the curve of the pressure difference is not linear in shape. It has been also shown that the air total change cannot be provided by only infiltration due to leakage particularly for such air-tight residential building in windy cold climate. Therefore, mechanical ventilation is required to compensate for the lack of it. A quantitative evaluation of IAQ based on the total volatile organic compounds (TVOCs) concentration has been done. The effect of the wind speed velocity and the temperature of the stairwell on the VOTCs concentration at each floor have been also presented.