常温注水井对含水层热贯通的影响机理分析

Mechanism Analysis of Heat-transfixion Influenced by Normal Temperature Water Injection Well in Groundwater Source Heat Pump

为探究常温注水井对水源热泵热贯通现象的影响,利用FlowHeat1.0软件模拟了3组情景下含水层渗流场、温度场时空分布特征,并分析了常温注水井对含水层热贯通的影响机理和抽水井水温变化规律。结果表明,常温注水井通过减小回灌井、常温注水井之间的水力坡度和延长地下水渗透途径的方式达到缓解热贯通的效果;回灌井、常温注水井流量比相同时,常温注水井在抽灌井连线的位置对含水层热贯通的影响小;抽灌量不变时,常温注水井与回灌井的流量比越大,常温注水井缓解热贯通的效果越明显;在有利地下水回灌的水源热泵系统中,布设常温注水井能有效地降低含水层热贯通程度。

The characteristics of seepage field and temperature field of groundwater source heat pump system at three scenarios were simulated by FlowHeat1.0. Meanwhile the heat transfixion mechanism and characteristics of temperature variation in pumping wells caused by normal temperature water injection well were analyzed. The results show that the normal temperature water injection well has great impact on the heat transfixion, which was based on reducing the hydraulic gradient between recharge and normal temperature injection well as well as prolonging the seepage path. When the flow ratio between recharge well and normal temperature injection well is the same, the position of the normal temperature injection well which located on the long axis has less influence on the heat transfixion. When the pumping rate keeps a constant, the larger flow ratio between normal temperature injection well and recharge well, the more obvious effect has been gotten for normal temperature injection well to relax heat transfixion pressure. Consequently, the normal temperature water injection well would relax heat transfixion pressure as long as the recharging condition was allowed in the groundwater source heat pump system.