Numerical Simulation On Underground Garage Ventilation System

In recent years, inductive ventilation system has been widely used for its space-saving, easy installation, high efficiency and energy saving. But its design and ventilation method is lack of mature theoretic sustainment. On this basis, the underground car park used inductive ventilation system is simulated, which the velocity and concentration distributions were drew.First, this paper measured the velocity of a single inducement fan. After repeating simulations, comparing with the tested results, the correct mathematical model and boundary conditions were finally obtained, which verified the reliability of the simulation work. As the different factors of impact on the ventilation efficiency, we established small-space modes to simulate the inducement fan in the design of the optimal layout,such as nozzle inclination angle, inducing fan horizontal and vertical spacing, inducing fan layout plan and so on. In addition, the transient field on the distribution of CO concentration was simulated, by analyzing the concentration distribution, the age of air and flow line distribution, which vividly shows the process of entire distribution.Furthermore, different plan in the design of inductive ventilation system for an underground car park in the city of Wuhan were used to simulate, and analysis of the difference between CO concentration field. By comparing the ventilation efficiency in the situations of on and off for inducement fans, the results show that the concentration distribution of CO is more uniform when turning on inducement fans, and the ductless inductive ventilation system plays a good role of dilution.