严寒地区太阳能土壤源热泵土壤温度场特性

Soil temperature field characteristics of solar energy assisted by ground source heat pump in severe cold area

为了解决严寒地区地源热泵长期运行所引起的土壤温度逐年降低问题,建立了太阳能全年补热的土壤源热泵系统模型.结合某办公建筑土壤源热泵项目,建立了2口120 m深U形垂直埋管试验井,进行热响应试验,得出制热工况与制冷工况的土壤导热系数与热扩散系数分别为1.883 W·(m·K)^(-1)和7.608×10^(-7)m^2·s^(-1);制冷工况的导热系数与热扩散系数分别为1.758 W·(m·K)^(-1)和9.203×10^(-7)m^2·s^(-1).利用TRNSYS软件平台模拟了土壤温度场变化,结果表明:热泵运行10年的土壤温度降为5.17℃,获得了供暖、供冷、过渡季节的太阳能联合土壤源热泵系统的土壤温度的恢复情况.

To solve the problem of soil temperature reducing year by year due to long-term operation of ground source heat pump in severe cold area,combined with a ground source heat pump project of office building,a model of ground source heat pump was established to integrate with continuously yearly solar supplement heat. Two vertical U-tube test wells with 120 m depth were built to carry out thermal response test. Thermal conductivity and thermal diffusivity heating conditions were respectively 1. 883 W ·（ m·K）^（-1）and 7. 608 × 10^（-7）m^2·s^（- 1）,and refrigeration thermal conductivity and thermal diffusivity conditions were respectively 1. 758 W ·（ m·K）^（-1）and 9. 203 × 10^（- 7）m^2·s^（- 1）. The soil temperature field was simulated by TRNSYS. The results show that the soil temperature drop is 5. 17 ℃ after 10 years operation of ground source heat pump,and the soil temperature restoration characteristics of solar-assisted ground source heat pump system are obtained in supply heating season,supply cooling season and transition season.