应用于地铁隧道毛细管换热器的管间距分析

Analysis on tube spacing of capillary heat exchanger installed in subway tunnel wall

地铁隧道毛细管换热器是将毛细管网敷设于地铁隧道岩壁,作为热泵系统的前端换热器.采用CFD仿真软件,建立物理模型,分析不同管间距下地铁隧道毛细管换热器的冬夏季换热特性,结合系统调节及运行情况,得出适用于地铁隧道毛细管换热器最佳管间距.经分析,毛细管管间距与管内水流速共同影响毛细管水流量,从而影响毛细管的换热量.当管间距为20-30mm,流速控制在0.04-0.08m/s时可以在保证毛细管换热器换热量的基础上,降低系统总阻力,方便系统调节运行.

In subway tunnel, capillary tubes network heat exchanger is a capillary network laying on a subway tunnel wall, as the front of the heat exchanger in heat pump system.Heat transfer characteristics of the capillary tube in diffident tube spacing are analyzed in summer and winter conditions by CFD. The best tube spacing of capillary heat exchanger can be obtained by analyzing system layout and running conditions. Through the analysis, the water flow in capillary tubes is decided by tube spacing and flow velocity, which influences capillary tubes heat exchange capacity. When the tube spacing is about 20-30 mm, and velocity is about 0. 04-0. 08 m/s can guarantee on the basis of the capillary tube heat exchanger heat, effectively reduce system resistance, convenience adjusting and system running.