In order to investigate the alternate operation characteristics of a solar-ground source heat pump system(SGSHPS),various alternate operation modes are put forward and defined.A two-dimensional mathematical model wi...In order to investigate the alternate operation characteristics of a solar-ground source heat pump system(SGSHPS),various alternate operation modes are put forward and defined.A two-dimensional mathematical model with freezing/melting phase changes is developed for the heat transfer analysis of the soil.Based on the numerical solution of the model,the variation trends of underground soil temperature of the SGSHPS operated in various alternate operation modes are discussed.The results indicate that,for the day-night and short-time interval alternate operation modes without solar energy,the operation time fraction of a solar heat source should be confined to from 50% to 58% when operated in an alternate period of 24 h.Meanwhile,the disadvantages of a natural resumption of soil temperature can be overcome effectively by solar energy filling,and an optimal operation effect can be achieved by integrating the mode of solar energy filling with other alternate modes.In addition,the accuracy of the presented model is verified by the experimental data of borehole wall temperatures.The conclusions can provide a reference for the optimization operation of the SGSHPS.展开更多
为探索多能互补的清洁能源供暖技术,满足北京市村镇分散式建筑清洁供暖需求,在北京农村地区建设太阳能-地源热泵复合式系统,进行太阳能补热热泵供暖实验,并利用COMSOL软件开展地温场热均衡模拟研究。结果表明:相较单一地源热泵系统,太...为探索多能互补的清洁能源供暖技术,满足北京市村镇分散式建筑清洁供暖需求,在北京农村地区建设太阳能-地源热泵复合式系统,进行太阳能补热热泵供暖实验,并利用COMSOL软件开展地温场热均衡模拟研究。结果表明:相较单一地源热泵系统,太阳能补热热泵供暖方案下,地源侧出水温度提升23%,系统制热能效比(Coefficient of Performance,COP)和机组COP分别提升19%、25%;系统运行10 a,地源热泵系统单季节运行方案下总的取热量要多于间歇期自然恢复量,地温场总均衡为-8.91×10^(9)kJ;单一地源热泵方式运行和太阳能补热方式运行在双季节情况下总的取热量小于总的排热量,地温场总均衡分别为4.220×10^(9)、1.084×10^(10)kJ。因此,双季节运行方案对地温场不会产生负均衡,反而会对地温场有一定的热量补充。地源热泵系统运行中加入太阳能补热,对地温场的影响更小,可显著提升系统和机组效率,该模式适用于北京农村地区特别是供暖需求较大的建筑。展开更多
基金The National Key Technology R&D Program of Chinaduring the 11th Five-Year Plan Period(No.2008BAJ12B04)China Postdoctoral Science Foundation(No.20090461050)+1 种基金the Project of Researchand Development of Ministry of Housing and Urban-Rural Development ofChina(No.2008-K1-26)the New Century Talent Project of Yangzhou University for Excellent Young Backbone Teacher(2008)
文摘In order to investigate the alternate operation characteristics of a solar-ground source heat pump system(SGSHPS),various alternate operation modes are put forward and defined.A two-dimensional mathematical model with freezing/melting phase changes is developed for the heat transfer analysis of the soil.Based on the numerical solution of the model,the variation trends of underground soil temperature of the SGSHPS operated in various alternate operation modes are discussed.The results indicate that,for the day-night and short-time interval alternate operation modes without solar energy,the operation time fraction of a solar heat source should be confined to from 50% to 58% when operated in an alternate period of 24 h.Meanwhile,the disadvantages of a natural resumption of soil temperature can be overcome effectively by solar energy filling,and an optimal operation effect can be achieved by integrating the mode of solar energy filling with other alternate modes.In addition,the accuracy of the presented model is verified by the experimental data of borehole wall temperatures.The conclusions can provide a reference for the optimization operation of the SGSHPS.
文摘为探索多能互补的清洁能源供暖技术,满足北京市村镇分散式建筑清洁供暖需求,在北京农村地区建设太阳能-地源热泵复合式系统,进行太阳能补热热泵供暖实验,并利用COMSOL软件开展地温场热均衡模拟研究。结果表明:相较单一地源热泵系统,太阳能补热热泵供暖方案下,地源侧出水温度提升23%,系统制热能效比(Coefficient of Performance,COP)和机组COP分别提升19%、25%;系统运行10 a,地源热泵系统单季节运行方案下总的取热量要多于间歇期自然恢复量,地温场总均衡为-8.91×10^(9)kJ;单一地源热泵方式运行和太阳能补热方式运行在双季节情况下总的取热量小于总的排热量,地温场总均衡分别为4.220×10^(9)、1.084×10^(10)kJ。因此,双季节运行方案对地温场不会产生负均衡,反而会对地温场有一定的热量补充。地源热泵系统运行中加入太阳能补热,对地温场的影响更小,可显著提升系统和机组效率,该模式适用于北京农村地区特别是供暖需求较大的建筑。