Heat, vapor, and CO2 transportation caused by airflow in high-rise residential buildings

Abstract

Vertical and horizontal airflow occurs in high-rise buildings caused by wind pressure and temperature differences (thermal buoyancy), and heat, water vapor, and contaminants are transported along the air movement in high-rise buildings. To characterize transportation of the heat, water vapor, and contaminants with the airflow in a high-rise building, long-term measurements were taken in a high-rise residential building in Seoul, Korea, during the winter season. The analyzed building has 31 floors above ground and 5 floors underground and the height is approximately 110 m. The temperature, water vapor, and CO2 levels were measured at the elevator hall of the 7th floor, 13th floor, and 29th floor of the analyzed building.The measurement results indicated that the concentrations of heat, humidity, and contaminants (CO2) on the upper floors were all high compared to the lower floors because the outdoor air flows into the lower floors, moves upward through vertical shafts, such as the elevator core and staircases, and flows into the upper floors. This is due to the movement of heat, water vapor, and contaminants along the vertical air movement in high-rise buildings. In addition, the concentrations of heat, humidity, and CO2 in the high-rise residential building were the highest at the neutral pressure level (NPL, 13th floor) of the analyzed building. This is attributed to the poor ventilation performance at the NPL in high-rise buildings. As a result, the people who live on upper floors could be exposed to higher temperatures, humidity, and contaminants compared to those living on the lower floors in high-rise residential buildings.