【作者】 余鑫；

【导师】 王如竹； 翟晓强；

【作者基本信息】 上海交通大学 ， 制冷与低温工程， 2011， 博士

【摘要】 利用浅层地热能与热泵技术相结合形成的为建筑物供暖、制冷的地源热泵空调系统是可再生能源利用的有效方式。地源热泵空调系统目前主要应用在普通舒适性空调中,但对室内环境需要常年提供恒温恒湿空调的系统,地源热泵在这类系统中的应用研究还鲜有报道。这类系统对空调需求稳定、能源消耗较大。本文针对恒温恒湿空调的特点以及夏热冬冷地区的气候特点,深入研究了竖直埋管地源热泵恒温恒湿空调系统。主要内容包括:(1)为研究竖直埋管地源热泵空调系统在恒温恒湿环境中的运行特性,建立竖直埋管地源热泵恒温恒湿空调系统理论分析模型,对地源热泵空调系统的运行性能、地下埋管换热器与土壤的换热量和钻孔周围土壤温度分布进行预测。(2)为了对竖直埋管地源热泵恒温恒湿空调系统进行实验研究以及对理论模型进行验证,以上海地区某档案馆建筑为对象,构建竖直埋管地源热泵恒温恒湿空调实验系统。建筑面积8000m~2。系统主要包括地下埋管换热器、两台额定制冷量为594kW的热回收型地源热泵机组以及再热采用冷凝热回收的恒温恒湿机组。其中地下埋管换热器包括80m深、直径160mm的钻井280个,每个钻井内布置DN32单U型管。制冷工况运行时,采用冷凝热回收技术,将一部分冷凝热用于恒温恒湿机组内空气的再热,这样不仅减少了向土壤排放的热量,而且用冷凝热代替了常用的电加热来再热空气,节省了这部分的电能。(3)对系统进行理论预测,预测得出上海地区全年地下埋管换热器向土壤散热量为2630GJ,从土壤中吸热为2114.7GJ,热不平衡率为19.6%。在初始温度为18℃时,运行一年后距钻孔周围土壤温度上升为18.76℃。(4)对地源热泵恒温恒湿空调系统进行全年实验研究。得出冬季典型工况下,热泵机组制热COP达到5.2;夏季典型工况下,机组制冷COP达到5.1。连续运行一年,室内温湿度控制在规定范围内,满足国家规范要求。地源热泵空调系统在一年的运行时间内土壤温度上升了0.7℃左右,冷凝热回收对缓解土壤热堆积的贡献是68.14%。(5)利用理论分析模型,结合实验研究,对系统长时间运行性能进行预测,找到合理的运行控制策略。结果表明随埋管间距的增加,土壤温度上升变慢,有利于系统稳定运行,建议上海地区竖直埋管地源热泵恒温恒湿空调系统选择埋管间距4m~5m,埋管深度80m~100m。系统连续运行15年后,采用热回收技术时土壤温度上升幅度比不采用热回收时降低66.98%;室内设定20℃时,土壤温度上升2.80℃,而如果室内设定为22℃,则仅上升1.03℃,土壤温度上升幅度降低63.21%。(6)地域性分析表明,北京地区采用冷凝热回收技术可以解决土壤热不平衡问题;成都地区需要在热回收技术的基础上提高室内设定温度为22℃才可以解决土壤热不平衡问题;沈阳地区可以通过降低室内设定温度为18℃来解决土壤热不平衡问题。更多还原

【Abstract】 The ground source heat pump (GSHP) system, which combines the shadow geothermal and the heat pump to serve buildings with heat and cold energy, is an effective method for sustainable energy application. The application of GSHP system mainly covered in conventional buildings. However, few investigation is carried out for GSHP system applying in some buildings, which require the indoor enviroment to keep constant. The energy cost of air-conditioning is large in these buildings. Based on the special of constant temperature and humidity air-conditioning system and climate of hot summer and cold winter zone, the vertical-pipe ground source heat pump constant temperature and humidity air-conditioning system was analyzed. The main work are summarized as follow:(1) For analyzing the performance of the GSHP constant temperature and humidity air- conditioning system, the mathematical model was built.(2) The constant temperature and humidity air-conditioning system in the archives building in Shanghai covers an area of 8000m~2. The system consisted of ground heat exchanger, two heat pumps with heat recovery and AHU (air handling unit). The ground heat exchanger consisted of 280 vertical boreholes with the depth of 80 m. The distance between the boreholes is 4 m. The diameter of the borehole is 160 mm. There is a single PE U-tube with the outer diameter of 32 mm in each borehole. When operated in cooling mode, part of heat from condenser was used to reheat the air in AHUs, which would reduce the heat rejected to the soil.(3) The performance of the system, the heat exchange of the ground heat exchanger and soil, and the temperature distribution of soil are predicted by mathematical model of the constant temperature and humidity GSHP system. It is shown that the total heat rejected to soil is a year is 2630GJ while the heat absorbed from soil is 2114.7GJ in Shanghai. The unblance rate is 19.6%.(4) Experiments of all-year operating modes are carried out. Under the typical winter weather condition of Shanghai, the average COP was 5.2. For the typical summer weather condition, the average COP was 5.1. During the whole year, the indoor environment met the“Archives Design Code”issued by China national archives. The temperature of soil increased 0.7℃after one year operation. The contribution rate of heat recovery to the heat unbalance was 68.14%.(5) The long-term performance of the system is predicted with the mathematical mode combined the experimental data. It is shown that the soil temperature increases slower with the distance of the borehole increases, which is helpful for the system operates stably. The borehole distance and deepness are suggested to be 4m-5m and 80m-100m respectively in Shanghai. After 15 years operation, the increment of soil temperature with hear recovery was 66.98% lower than without heat recovery. After 15 years operation, the soil temperature increases 2.80℃with indoor set temperature 20℃while 1.03℃with indoor set temperature 22℃, the increment of soil temperature was reduced by 63.21%.(6) The region analysis showed that the thermal unbalance of soil could by solved by heat recovery in Beijing; Beside the hear recovery, the indoor set temperature should be increased to 22℃to solved the thermal unbalance in Chengdu; In Shenyang, the thermal unbalance could be solved by reducing the indoor set temperature to 18℃.更多还原