跨季节地埋管储热性能模拟及分析

Simulation and Analysis of Performance of Seasonal Borehole Thermal Energy Storage

地埋管储热(BTES)是解决太阳能间歇性、季节性等问题的有效手段之一。本文以串联连接的地埋管群为研究对象,基于解析解和数值解的混合解,建立地埋管群储热模型,并验证了模型的有效性。系统连续运行5年,储热体平均温度逐渐在一个稳定的范围内变化,注热量和取热量逐渐趋于稳定。以影响系数IC为指标进行敏感性分析,模拟钻孔间距、钻孔深度、土壤导热系数及土壤体积热容四个参数对BTES效率的影响。结果表明,钻孔间距和土壤导热系数是影响BTES效率的最主要参数。在稳定工况下,钻孔间距的IC值在0.02~0.44范围内,土壤导热系数的IC值在0.2~0.23范围内。

Borehole thermal energy storage(BTES) is one of the effective ways to solve the intermittent and seasonal problems of solar energy. The borehole group in series way is taken as the research object Based on the mixed solution of analytical solution and numerical solution, the corresponding mathematical model is established and its validity is verified. The system has been running continuously for 5 years, the average temperature of the heat storage volume gradually changes within a stable range, and the heat injection and heat extraction have gradually stabilized.The Influence Coefficient(IC) is used as an indicator for sensitivity analysis to simulate the impact of borehole spacing, borehole depth, soil thermal conductivity and volumetric heat capacity on the efficiency of BTES. The results show that the hole spacing and soil thermal conductivity are the most important parameters affecting the efficiency of BTES. The IC value of the borehole spacing is in the range of 0.02~0.44, and the IC value of the soil thermal conductivity is in the range of 0.2~0.23 in stable conditions.