地下长距离管廊跨防火分区通风换热数值模拟研究
Numerical simulation on ventilation and heat transfer of long-distance underground municipal tunnels across fire-prevention divisions
摘要:
针对工程应用中常出现的综合管廊通风区间大于防火区间的不匹配问题,本文研究了管廊中防火门对管廊内通风降温的影响及防火门处气流的运动规律。采用CFD方法建立了管廊综合舱和电力舱的数值模型,研究了全年3个典型季节(冬季、夏季、过渡季)管廊运行温度沿长度方向的变化规律。研究发现:通风区间跨防火分区的通风换热方式是可行的;在不跨防火分区的夏季送风工况中,综合舱需要4 h-1的换气次数来实现降温效果,电力舱需要6 h-1的换气次数;在跨防火分区工况中,设置防火门可以加强防火门后的局部换热,减小通风换气次数。
Abstract:
In view of the mismatch that the ventilation section of the comprehensive municipal tunnels is larger than the fire-protection section in engineering applications, the influence of the fire doors on the ventilation cooling in the underground municipal tunnel and the airflow movement law at the fire doors are studied. The CFD method is used to establish the numerical models of the municipal tunnel and the cable tunnel. The operating temperature changes along the length of the underground municipal tunnel during the three typical seasons (winter, summer, transition season) of the whole year are studied. It is concluded that the ventilation and heat transfer mode of the ventilation section across the fire-prevention division is feasible. In the summer condition without across the fire-prevention division, the municipal tunnel needs 4 h-1 air change rates to achieve the cooling effect, and the cable tunnel needs 6 h-1 air change rates. In the condition across the fire-prevention division, setting the fire door can strengthen the local heat transfer behind the fire door and reduce the air change rates.
Keywords:undergroundmunicipaltunnel;fire-preventiondivision;ventilationandheattransfer;ventilationsection;firedoor;airchangerate