高寒地区中深层地源热泵系统运行表现分析
Operation performance analysis of middle-deep ground-source heat pump systems in high cold area
摘要:
对青海省共和县中深层地源热泵集中供暖系统实际运行情况展开了研究。通过室内外温度、取水与回灌水温度、供回水温度、能耗和性能系数等数据,综合分析了供热系统实际运行表现。研究结果表明,地热水出水温度存在0.078 ℃/d的衰减率,为维持地热动态平衡,取水上限流量为80 m3/h。此外,天气转暖过程中室外平均温度5 ℃可看作热泵机组启停节点,关闭地源热泵机组仅靠板式换热器换热,能使系统综合性能系数最大升至8.7,系统能耗降幅达42.9%。本文可为地热供暖系统优化运行及能效提升提供参考。
Abstract:
A study is conducted on the actual operation of the middle-deep ground-source heat pump centralized heating system in Gonghe county,Qinghai province.The actual operation performance of the heating system is comprehensively analysed through data such as indoor and outdoor temperatures,extraction and reinjection water temperatures,supply and return water temperatures,energy consumption,and coefficient of performance.The research results show that there is a decay rate of 0.078 ℃/d for the geothermal water outlet temperature.To maintain the geothermal dynamic balance,the upper limit flow rate of water extraction is 80 m3/h.In addition,when the weather warms up,an outdoor average temperature of 5 ℃ can be regarded as the start-stop node of the heat pump unit.Closing the ground-source heat pump unit and relying only on the plate heat exchanger for heat transfer can maximize the comprehensive coefficient of performance of the system to 8.7,and the system energy consumption can be reduced by 42.9%.This paper can provide a reference for the optimized operation and efficiency improvement of geothermal heating systems.
Keywords:middle-deep ground-source heat pump; high cold area; geothermal water; centralized heating; plate heat exchanger; coefficient of performance(COP)