网箱式换热器在某地表水地源热泵系统中的应用研究
Application of cage-type heat exchanger to a surface water-source heat pump system
摘要：
针对地表水温度分层现象，提出了一种可以纵向梯级利用地表水温度的网箱式换热器。以合肥地区浅层地表水为研究对象，测量了一年中不同深度地表水温度的变化情况，分析了网箱式换热器换热管道长度和循环水量对换热效果的影响。实测和模拟分析了换热管道运行对管外水温影响。研究表明：1） 增加管道长度可以增强换热，但到一定长度后则不再强化传热；2） 同一水深下换热效果随着循环水量增加而增强，但流量增大到一定程度时，换热效果反而变差；3） 循环水量相同时，水越深，换热效果越好；4） 越接近水表面，换热器管道之间传热影响越明显，上下层管道之间不应采用等间距。
Abstract：
Aiming at the phenomena of surface water temperature stratification, proposes a cage-type heat exchanger to achieve longitudinal cascade utilization of surface water. Taking the shallow surface water of Hefei area as a research object, measures the yearly changes of water temperature in different depth, and analyses the influences of cage-type heat exchanger’s pipe length and the flow rate of circulating water on the heat transfer effect. Tests and simulates the influence of heat exchange pipe operation on water temperature outside the tube. The results show that: 1) increasing the pipe length can enhance the heat transfer, but to a certain length no longer strengthen the heat transfer; 2) increasing the flow rate of circulating water can enhance the heat transfer in the same depth, but when flow rate increases to a certain extent, it will reduce the heat transfer effect; 3) when the flow rate of circulating water is the same, the deeper the water, the better the heat transfer effect; 4) the more closer to the surface, the more obvious the heat transfer effect between heat exchanger pipes, therefore, equal space between the upper and lower pipes shall not be used.
Keywords:cage-typeheatexchanger,shallowsurfacewater,cascadeutilization,heattransfereffect,ground-sourceheatpump