人工流场影响下地埋管管群换热的模拟研究
Simulation Study on Heat Transfer of Buried Pipe Banks Under the Influence of Artificial Flow Field

针对地源热泵系统运行时出现的地埋管周围冷热量堆积的问题, 提出了在地埋管管群两侧加抽水井和回灌井来产生人工流场, 从而强化地埋管管群换热效果的方法．通过FEFLOW软件模拟了人工流场影响下地埋管的换热, 对单个地埋管的换热进行了单因素敏感性分析, 模拟了水井数量以及流场切换时间对地埋管管群换热效果的影响．结果表明：在选定工况下, 加入人工流场后地埋管的换热量较无流场时均有较大提高, 其中单个地埋管在流场定期切换与不切换情况下的换热量可较无流场时分别提高54.06% 和69.67% ; 设置有1组水井、2组水井、3组水井的地埋管管群的平均换热量与无人工流场时相比分别提高了9.89% 、21.54% 和33.00% ; 人工流场的切换时间越长, 地埋管管群的换热效果越好, 但随着切换时间的增长, 平均换热量提高的幅度减小．
With the running of ground source heat pumps，the cold or heat accumulates around the buried pipes. As for the problem，a solution that adds pumping well and recharge well on either side of buried pipe banks in order to enhance the heat transfer of buried pipe banks was put forward. FEFLOW software was used to simulate the heat transfer of buried pipe banks under artificial flow condition. Single factor sensitivity analysis for one buried pipe was conducted. For buried pipe banks，numbers and the switching time interval of artificial flow were taken into account. The results show that: with artificial flow，the heat transfer amount always has a larger increase compared with no flow. For single buried pipe，the heat transfer amount improves 54.06% and 69.67% respectively in the conditions of flow direction switching periodically and no flow direction switching. In comparison with no flow，the average heat transfer amount of buried pipe banks improves 9.89% ，21.54% and 33.00% respectively in the conditions of one group of wells，two groups of wells and three groups of wells. The longer the switching time interval of artificial flow，the higher the heat exchange amount，but with the growth of the switching time interval，the growth rate of average heat transfer amount decreases