金融街地下交通工程通风系统流动特性分析

采用计算流体力学的方法,对金融街地下交通工程通风系统的流场特性进行了数值分析,研究了各分系统流场的均匀特性、各通风管道内部流场细节和各分系统可靠性.结果表明:排风系统各风口的风速很不均匀,且高速风口处形成明显的气幕效应和旋涡区;在风道内形成明显的低速区.在送风系统中,各风口的风速基本均匀,风机的风压可满足要求;但在风道内也存在了明显的低速区或旋涡区.需要对该通风系统进行等风量设计,并对系统的内部气流组织进行改进设计,以提高通风系统的可靠性并降低能耗.

NUMERICAL SIMULATION INTO FLOW FIELDS OF VENTILATION SYSTEM IN FINANCIAL STREET UNDERGROUND TRANSPORT SYSTEM

Numerical analyses are conducted on internal flow fields of the ventilation system for China Financial Street underground transport system using computational fluid dynamics (CFD) method. The flow field uniformities of the sub-systems, flow details inside the vent-pipes and reliabilities of individual sub-systems are investigated. The results show that: velocities of air flow at vents, in air- exhausting sub-system, are far from uniform. The air-curtain phenomena are observed obviously near the vents, which lead to the vortices region behind the vents and low velocity regions. In air-supplying sub-systems, velocities of air flow at vents are nearly uniform and the pressure of the fans could satisfy the design requirement; however, obvious low velocity regions and vortices regions still exist in the vent-pipes. To improve the reliability and reduce the energy consumption of the ventilation system, redesign using equal-flowrate method needs to be conducted, and the internal flow structure needs to re-organized and improved as well.