Research On Underground Car Park Mechanical Ventilation System

At present, most underground car parks have been building in basements of the high-rise or the multi-storey buildings in order to solve the problems of car storage and scarce urban land. Vehicle activities when starting or stopping result in the emission of a number of harmful substances. Among them the carbon monoxide (CO) which affects human beings most severely is the main one. The enclosed nature in the underground garages makes the contaminants emitted from cars being difficult to diffuse. So the mechanical ventilation systems are installed in almost all underground garages. The purpose of ventilation in the underground garage is to dilute the contaminants emitted from cars to indoor criterion of carbon monoxide concentration limit. In order to ensure the good air quality and save energy in garage, we need to determine reasonable forms of ventilation and air distribution. There are two kinds of mechanical ventilation systems, they are no-duct inductive ventilation system and duct ventilation system.The paper bases on computational fluid dynamics theory and software FLUENT as the operational platform, numerical simulation analysis of the air distribution and contaminant density field of the ventilation of an underground garage is made to improve indoor air quality of underground garage. We can know the effect and characteristics of these two types of ventilation systems through the simulation and conclude that no-duct inductive ventilation system is much better than duct ventilation system.Meanwhile, this paper studies technique economic of mechanical ventilation system in an underground garage. In case of the same hardware of an underground garage, compare technique economic of no-duct inductive ventilation system to technique economic of duct ventilation system, dark mathematics is calculation tool. Make theoretical analysis on mathematical model, objects judged, weigh, the degree belonging to and so on, and calculate matrix. The results studied show that no-duct inductive ventilation system is superior to duct ventilation system in technique economic.