T2Well单井地下水源热泵水-热耦合数值模拟研究

SIMULATION FORWATER-HEAT COUPLING PROCESS OF SINGLE WELL GROUND SOURCE HEAT PUMP SYSTEMS IMPLEMENTED BY T2WELL

以北京地区实际井参数刻画的单井地下水源热泵为研究对象,利用T2Well模拟器对单井系统地源热泵运行过程进行全面模拟,并对主要参数进行敏感性分析,探究对单井系统生产井温度、热突破时间的影响。距离井筒相同位置不同深度的点,埋深越大受回灌水温度的影响越小。每个运行周期结束时,温度场分布都能得到一定程度的恢复(同一周期内初始温度场相比)。水平方向渗透率同垂向渗透率的比值越大,越有利于回灌水在含水层中的运移,可有效保证热泵系统的取热温差。初步预计一个单井水源热泵系统能满足北京地区约1.5万m^2面积建筑的供暖需求,约1.6万m^2面积建筑制冷需求。

Single well groundwater source heat pump(SWGSHP)described by a practical engineering case in Beijing is the object of this study.Water-heat coupling simulation is developed by T2Well simulator in this study.The sensitivity analysis of key parameters was carried out to explore the influence on temperature distribution and thermal breakthrough time.With the same distance to the well,the larger the buried depth is,the smaller the impact of recharging water temperature is.When an operation period is finished,temperature distribution can be restored partly to its initial state(for the same period).The bigger the value of kx/ky,the easier the re-inject water flow can transfer horizontally in the aquifer,which effectively guarantee the temperature difference of heating and cooling.It is preliminarily estimated that a SWGSHP systemcan meet heating demand of a building with area of about 15000 km^2 and cooling demand of a building with area of about 16000 km^2 in Beijing,China.