Study on Indoor Air Movement under the Crowding Conditions by Numerical Simulations and PIV Small-scale Experiments

Abstract

In the mechanical ventilation room, human body will block the air flows and change the original airflow organization. In the crowd places, the influence of the crowd may greatly change the indoor air movement and even worsen the environment. So the effect can not be ignored. The paper studied the influence of the human body to the indoor air movement by using the method of Particle Image Velocimetry (PIV) and numerical simulation (CFD). The PIV experiment and numerical simulation contain two conditions. One condition is an empty room and another contains models of human body in the room. The paper compared the result of experiment and numerical simulation. Numerical simulations are demonstrated to be accurate in the two conditions, and the Standard k-ɛ model most accurately predicts the flow in a room contains crowd model. In this study, the numerical simulation and measurements show that the crowds will greatly change the air distribution and the residence time of the flows in the building. Therefore, it is important that crowds be considered in ventilation design.