基于线热源理论的垂直U型埋管换热器传热模型的研究

基于经典常热流线热源理论,通过引入叠加原理、阶跃负荷及孔洞热阻思想将其发展为能够适用于变热流埋管换热与地源热泵系统模拟的变热流线热源模型,并与改进的经实验与理论验证的圆柱源理论模型进行了比较与分析。结果表明:所发展的变热流线热源模型能够有效地模拟地下埋管的换热过程,可作为地下垂直U埋管换热过程的计算模型,为地源热泵地下埋管换热器的设计计算及地源热泵系统的模拟提供了一种新的简单而又实用的计算方法。

STUDY ON HEAT TRANSFER MODEL OF VERTICAL U-TUBE GROUND HEAT EXCHANGERS BASED ON LINE HEAT SOURCE THEORY

Based on the line heat source theory of classic constant heat flux,the variable heat flux line source model was developed to simulate the heat transfer of ground heat exchanger and the operation performance of GSHPS operated in variable heat flux by quoting the idea of superposition principal,step load and borehole resistance.The validation of the updated line source model was undertaken by analysis and comparison with the improved cylindrical source model.The results indicated that the developed variable heat flux line source model can simulate the heat transfer process of ground heat exchanger effectively and can be used as an effective calculation model for vertical U-tube buried coil.The developed variable heat flux line source model provide a new type of simple and useful calculation method for the design of ground heat exchanger and the simulation of ground source heat pump system.