严寒地区空气-地源热泵耦合系统性能研究

Research on Performance of Air-Ground Source Heat Pump Coupling System in Severe Cold Region

提出一种结合相变蓄热地板的空气-地源热泵系统,为严寒地区机场辅助用房提供室内环境保障,满足供热、供冷和供生活热水的需求,采用数值模拟的方法研究其供暖期性能。相变蓄热地板能够对室内温度起到较好的调节作用,当室外温度为-25~-5℃时,有相变蓄热地板的室内温度在16.9~19.3℃范围内波动,满足人体舒适度的要求,对比无相变蓄热地板的室内温度,有相变蓄热地板的室内温差减小44%左右。室外温度对空气源热泵制热性能系数影响较大,制热性能系数随着室外温度降低而降低。在室外温度为-15℃时,空气源热泵的制热性能系数在2.3以上。随着室外温度降低,地源热泵的制热性能系数增加,室外温度低于-25℃时,地源热泵制热性能系数能够保持在4.4以上。供回水温差对地源热泵的制热性能系数影响较大,对空气源热泵的制热性能系数影响较小。当空气源热泵和地源热泵的启停切换温度为室外日平均温度-15℃时,整个供暖期热泵系统的平均制热性能系数最高达到4.2,最低为2.4,平均值为3.28。在保证土壤热平衡的前提下,通过调整空气源热泵和地源热泵的运行时间,优化了系统经济性和节能性。

An air-ground source heat pump system combined with phase-change heat storage floor is proposed to provide indoor environmental guarantee for airport auxiliary buildings in severe cold region and meet the needs of heating,cooling and domestic hot water supply.The heating performance of the system is studied by numerical simulation.The phase-change heat storage floor can play a better role in regulating indoor temperature.When the outdoor temperature is-25 to-5℃,the indoor temperature with phase-change heat storage floor fluctuates within the range of 16.9 to 19.3℃,meeting the requirements for human comfort.Compared to the indoor temperature without phase-change heat storage floor,the indoor temperature difference with phase-change heat storage floor decreases by about 44%.Outdoor temperature has a great influence on the heating coefficient of performance of air-source heat pump,and the heating coefficient of performance decreases with the decrease of outdoor temperature.When the outdoor temperature is-15℃,the heating coefficient of performance of the air source heat pump is above 2.3.As the outdoor temperature decreases,the heating coefficient of performance of the ground-source heat pump increases.When the outdoor temperature is lower than-25℃,the heating coefficient of performance of the ground-source heat pump can be kept above 4.4.The temperature difference between the supply and return water has a greater impact on the heating coefficient of performance of the ground-source heat pump,but has less impact on the heating coefficient of performance of the air-source heat pump.When the start-stop switching temperature of the air-source heat pump and ground-source heat pump is the outdoor daily average temperature of-15℃,the average heating performance coefficient of the heat pump system during the entire heating period reaches a maximum of 4.2,a minimum of 2.4,and an average of 3.28.On the premise of ensuring the soil heat balance,the system economy and energy saving are optimized by adjusting the running time of the air source heat pump and the ground source heat pump.