闭环地源热泵系统建模

目前国内对地源热泵的研究多集中在地热换热器的传热模型理论研究方面,而对地源热泵系统整体性能的研究则局限于实验测试,因此迫切需要建立一个地源热泵的系统模型来进行系统的优化设计和系统性能预测.采用理论解析方法建立了竖直U型埋管地热换热器的准三维模型,该模型考虑了两支管间的热短路问题,比现有模型更接近于实际工程.采用确定性模型法建立了热泵机组的模型,然后通过能量和质量守衡方程式建立了系统动态耦合模型.利用该模型即可预测在不同的地热换热器配置情况下,地源热泵系统的各项性能.试验表明,该系统模型预测结果与实测值吻合的较好.

The modeling of ground-coupled heat pump systems

At present,study on ground-coupled heat pump systems is heat transfer model of geothermal heat exchangers and system performance measurement in China.It is essential to establish a system model to optimize the design of geothermal heat exchangers and predict system performance.A quasi-three-dimensional model for vertical U tube has been developed in this article,which analyzes the impact of thermal "short-circuit",or thermal interference,between the U-tube legs on the performance of the ground exchanger,and is fairly closer to the case of practical engineering.The heat pump unit model has been set up with detailed deterministic approach.The dynamic system model is coupled with geothermal heat exchanger model and heat pump unit model,which is based on the conservation of mass and energy.The system performance can be predicted according to this model in the different layout of geothermal heat exchanger.Ideal agreement between the predicted and experimental results is obtained.