太阳能—地源热泵复合系统的模拟优化

发布时间：2018-02-04 14:37

本文关键词： 地源热泵交替蓄热冷热负荷不平衡 TRNSYS　出处：《山东建筑大学》2013年硕士论文　论文类型：学位论文

【摘要】：本文以实验为基础对螺杆地源热泵机组理论模型中的多变指数进行了修正,建立了螺杆地源热泵机组的灰箱模型,编写了以此灰箱模型为基础的螺杆地源热泵机组FORTRAN模拟程序。模拟了R22为制冷剂螺杆地源热泵机组的运行特性。分析夏季制冷、冬季制热两种运行工况下不同蒸发器入口水温、冷凝器入口水温及压缩机输气量对机组的制冷量、制热量、压缩机功耗及COP的影响。通过对热泵机组的模拟获得不同输气量条件下热泵机组随蒸发器入口水温和冷凝器入口水温变化的运行数据,以此数据为基础,结合地源热泵机组的实际控制方式在TRNSYS环境中搭建热泵机组模拟模块,此方法避免了热泵机组程序的重复计算加快了模拟速度,同时比简单的满负荷的启停控制策略增加了模拟精度,更加符合热泵机组的实际运行状况。使系统小步长的长时间模拟更加准确快速。对利用太阳能在5月1日到10月1日期间为地源热器蓄热的方法进行了模拟,验证了利用太阳能资源比较丰富的时间进行蓄热的可行性。确定了不同集热器面积下的太阳能蓄热水泵的流量的计算方法。提出了太阳能交替蓄热-地源热泵系统,以沈阳地区某建筑为具体研究对象,建立包括太阳能集热器、地源热泵机组、地源换热器、控制系统、气象参数、水泵和建筑负荷在内的复合系统的TRNSYS动态模型。对常规地源热泵系统和不同集热器面积的太阳能交替蓄热-地源热泵系统进行了长达9年的模拟。对常规地源热泵和不同面积太阳能集热器面积的太阳能交替蓄热-地源热泵系统的瞬时制热能力、制冷能力、制热能耗、制冷能耗进行了模拟,并进行了逐年积分,对于制热能力不足的系统引入冬季制热辅助热源(燃煤锅炉),把耗电折合成燃煤,得出了不同系统的综合能耗、能效、燃煤量,CO2、SO2、NO2的排放量。沈阳地区存在冷热负荷不平衡的问题,如果采用常规方式的地源热泵系统,这种冷热负荷的不平衡将造成地温均值的下降,从而引起冬季地源热泵机组的保护性停机,无法满足用户的冬季供热需求,而采用太阳能冬季补热的形式由于沈阳地区冬季太阳能集热效果差,需要较大集热器面积和集热效果更好的真空管热管集热器,极大的提高了初投资。而利用太阳能资源丰富的时间进行蓄热可以使用价格相对较低的平板型太阳能集热器即可达到较好的集热效果。得出了太阳能交替蓄热-地源热泵系统可以在不使用冬季辅助热源的情况下,实现地下温度场的动态稳定,既能改善地源热泵冬季供热能力不足又不会引起夏季制冷能力的下降,在所研究的建筑中平板型太阳能集热器面积达到400m2时,太阳能交替蓄热-地源热泵系统既可以为用户提供满足舒适度要求的冷热量,又具有较高的能效比和环境效益,是最优配置。
[Abstract]:On the basis of experiments, the variable exponents in the theoretical model of the screw ground source heat pump unit are modified, and the grey box model of the screw ground source heat pump unit is established. The FORTRAN simulation program of screw ground source heat pump unit based on the grey box model was compiled. The operating characteristics of the screw ground source heat pump unit R22 as refrigerant were simulated and the summer refrigeration was analyzed. The effects of inlet water temperature of evaporator, inlet water temperature of condenser and compressor gas delivery on the refrigerating capacity, heating capacity, compressor power consumption and COP of the unit under two operating conditions of heating in winter. Through the simulation of the heat pump unit, the operating data of the heat pump unit with the inlet water temperature of the evaporator and the inlet water temperature of the condenser are obtained under the condition of different air delivery rate, which is based on the data. Combined with the actual control mode of ground source heat pump unit, the simulation module of heat pump unit is built in TRNSYS environment. This method avoids the repeated calculation of heat pump unit program and accelerates the simulation speed. At the same time, compared with the simple full load start and stop control strategy, the simulation accuracy is increased, which is more in line with the actual operating condition of the heat pump unit, and makes the long time simulation of the system with small step size more accurate and fast. The method of using solar energy to store heat from May 1st to October 1st is simulated. The feasibility of using abundant solar energy resources to store heat is verified, and the calculation method of flow rate of solar energy regenerative pump under different collector area is determined. A solar alternately regeneration-ground source heat pump system is proposed. Taking a building in Shenyang area as a specific research object, the solar collector, ground source heat pump unit, ground source heat exchanger, control system and meteorological parameters are established. The TRNSYS dynamic model of the composite system including water pump and building load has been simulated for 9 years for conventional ground source heat pump system and solar alternate heat storage and ground source heat pump system with different collector area. The instantaneous heating capacity, refrigeration capacity, heating energy consumption and refrigeration energy consumption of conventional ground source heat pump and solar energy collector with different area are simulated. And year by year integral, for the system with insufficient heating capacity to introduce the winter heating auxiliary heat source (coal-fired boiler, power consumption into coal-fired, the comprehensive energy consumption of different systems, energy efficiency, coal-burning amount of CO _ 2. Emission of so _ 2o _ 2. There is the problem of unbalanced cold and heat load in Shenyang area. If the conventional ground source heat pump system is adopted, the imbalance of the heat and cold load will cause the decrease of the mean value of the ground temperature. Therefore, the protective shutdown of ground-source heat pump units in winter can not meet the heating needs of users in winter, but the solar energy heating in winter is not good because of the poor effect of solar energy collection in Shenyang in winter. The vacuum tube heat pipe collector with larger collector area and better collector effect is needed. The initial investment is greatly increased, and the use of solar energy rich time for heat storage can use relatively low price flat solar collector to achieve a better heat collection effect. It is concluded that the dynamic stability of underground temperature field can be realized without the use of auxiliary heat source in winter in the solar alternately regenerative ground-source heat pump system. It can not only improve the lack of heating capacity of ground-source heat pump in winter but also can not cause the decrease of cooling capacity in summer. When the area of flat solar collector reaches 400 m2 in the buildings studied. The alternative solar energy accumulation-ground source heat pump system can not only provide users with the cooling heat to meet the requirements of comfort, but also have a higher energy efficiency ratio and environmental benefit, so it is the best configuration.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU831

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