CFD simulation of ducted mechanical ventilation for an underground car park

Abstract

A mechanical ventilation system of an underground car park consisting of four basement levels with a total parking capacity of 835 cars is examined. The purpose of the current study is to undertake a performance-based assessment of the proposed alternative solution and to validate the performance of the proposed ventilation system of the car park by the use of computation fluid dynamics (CFD) at design conditions. Generally, the proposed car park ventilation system design is considered not acceptable and needs to be modified. This is because the average Carbon Monoxide (CO) concentration levels at 1.5 m above floor level throughout most of the car park areas is around 60 ppm or more. Moreover, significant areas of Basement 1 and Basement 4 are higher than the maximum allowed peak CO concentration of 100 ppm. The results have indicated that the current amount of the supplied air system is not sufficient and needs to be increased in order to ventilate the car park and meet the performance requirements.