基于线热源理论预测地埋管出口水温的简化方法
Simplified method for forecasting outlet water temperature based on line heat source theory
摘要:
地源热泵系统出口水温对于判断热泵运行效率及地埋管换热状况有重要意义。参照地源热泵设计规范中推荐的地埋管传热热阻计算公式,基于地埋管传热的线热源理论模型,提出了一种预测逐时地埋管出口水温的简化方法。用数值模拟软件建立了地源热泵系统传热模型,得到了出口水温的逐时变化。结果表明,模拟方法能较好地预测出口水温的变化。分析了机组运行周期、负荷、日运行时间对简化方法预测结果精确度的影响,结果表明简化方法可用于指导地埋管长度计算。
Abstract:
The outlet water temperature of groundsource heat pump system has great significance for determining the pump efficiency and the status of the ground heat exchanger. Based on the technical code for groundsource heat pump system and line heat source theory, proposes a simplified method to predict the hourly outlet water temperature of buried pipe. Establishes a heat tranfer model of the groundsource heat pump system by simulation software, and obtains the hourly variation of outlet water temperature. The result shows that the simulation method can accurately predict the change of outlet water temperature. Analyses the influence of the operation period, load and daily operation time on accuracy of the outlet water temperature prediction by simplified method, and the result shows that the simplified method can be used to calculate the length of buried pipe.
Keywords:line heat source model, buried pipe, simplified method, outlet water temperature, resistance of heat transfer, simulation