首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
首先,对直接膨胀式地源热泵的性能进行了理论分析.与常规地源热泵相比,直接膨胀式地源热泵的地埋管换热器热阻更小,在制冷工况下具有更低的冷凝温度,在制热工况下具有更高的蒸发温度,因此它具有更高的性能系数.直接膨胀式地源热泵系统无需二次换热回路和循环水泵,因此具有更高的系统性能系数.然后,根据实测数据对直接膨胀式地源热泵实验系统的性能进行了分析.该实验系统建立在中国湘潭,其U形垂直地埋管换热器置于水井之中,地埋管换热器的长度为42m,外径为12.7mm.测试结果表明,在制热工况下此直接膨胀式地源热泵系统的性能系数最大值为5.95,平均值为4.72.  相似文献   

2.
为进一步提高太阳能利用效率和太阳能辅助空气源热泵供热系统的性能,提出了一种新型太阳能空气源热泵供热系统,并研究了该供热系统的性能和特性.基于自行设计的10kW空气源热泵,建立了供热系统的数学模型,通过模拟得出了不同环境温度和出水温度下供热系统的运行特性和性能规律.结果表明:基于新型太阳能辅助空气源热泵供热系统,热泵的性能得到较大的提高.当环境温度为7℃时,空气源热泵的COP最大可增加26%.这为进一步研究新型太阳能辅助空气源热泵供热系统在供暖季节的性能奠定了基础.  相似文献   

3.
《家用空气源热泵辅助型太阳能热水系统技术条件》中对整机综合制热性能系数(COP)试验的平均环境温度和全天太阳能辐照量给出了一定变化范围,为研究这一变化对整机综合COP的影响,将整机的性能试验分两个阶段进行,其中太阳能热水系统加热段在户外进行,空气源热泵加热段在环境温度可控的环境试验室进行。试验表明在标准规定的变化范围内,平均环境温度的变化及全天辐照量的变化对空气源热泵辅助太阳能热水系统整机综合COP有较大影响.其中因平均环境温度的变化及全天辐照量的变化对太阳能热水系统性能影响而引起整机综合COP的变化较小.而因平均环境温度的变化对空气源热泵性能的影响而引起整机综合COP的变化最大可达40%左右。据此对该标准的试验方法、试验条件提出了修改建议。  相似文献   

4.
太阳能供热采暖系统是指将太阳能转换成热能,供给建筑物冬季采暖和全年其他用热的系统。本研究提出了太阳能-空气源复合热源热泵系统,采用辅助加热炉为辅助热源和采用辅助热泵为辅助热源,系统由集热模块、控制模块、采暖模块组成,采用防过热选择性吸收涂层的集热器和防过热旁路散热器,解决了系统过热问题;同时对空气源热泵、辅助加热设备与太阳能集热器结合系统的运行性能进行了研究,优化了系统运行控制策略。  相似文献   

5.
A mathematical optimization model was set up for a ground-solar combined system based on in-situ experimental results,in which the solar collector was combined serially with a ground-coupled heat pump(GCHP).The universal optimal equations were solved by the constrained variable metric method considering both the performance and economics.Then the model was applied to a specific case concerning an actual solar assisted GCHP system for space heating.The results indicated a system coefficient of performance(COP)of 3.9 for the optimal method under the seriaI heating mode,and 3.2 for the conventional one.In addition,the optimum solution also showed advantages in energy and cost saving.1eading to a 16.7%improvement in the heat pump performance at 17.2%less energy consumption and 11.8%lower annual cost,respectively.  相似文献   

6.
分析福州地区典型气象年数据,表明该地区全年太阳辐射量和日照时数较大,太阳能和空气能资源较为优越。综合考虑入射太阳光余弦效应、太阳辐照量和热水负荷的变化,3种不同方法分别计算得到集热器最佳倾角,并比较分析倾角精确度及对应辅助加热量,最大限度地提高系统太阳能利用率,为实际太阳能热泵系统应用提供可靠理论支持。  相似文献   

7.
Theoretical and experimental analysis of a new refrigerant mixture BY-3 was conducted based on a single-stage vapor compression refrigeration system. The water-water heat pump system used BY-3 to produce hot water when the low temperature was 20 ℃. The following results were obtained: the highest temperature at the condenser outlet reached about 85 ℃; when the difference between the water temperatures at the condenser outlet and the evaporator inlet was less than 40 ℃, the coefficient of performance (COP) was larger than 4; when the difference reached 55 ℃, the COP still kept 3; the discharge temperature of BY-3 was lower than 100 ℃, and the refrigerant vapor pressure kept lower than 1.8 MPa. When the water temperature at the condenser outlet reached over 85 ℃, nearly a 5 ℃ superheating temperature was maintained.  相似文献   

8.
Sewage source heat pump unit operates under partial load most of the time, and study on the law of coefficient of performance (COP) of the unit varying with load ratio can provide basis for the heat pump units running in high efficiency. A mathematical model determining COP, evaporation temperature and condensation temperature of a single unit was proposed. Under the condition of uniform load distribution, the model was established according to different ways of bearing partial load with the same type multiple units but different parallel operation models, and the operation characteristics of units were analyzed as well. Results show that the single screw water-source heat pump can maintain high COP only at 60%—100% load ratio, COP decreases sharply with the decrease of load ratio, and the units with parallel operation are controlled by the load ratio of a single unit according to the reduction of total load which can keep the average COP at high level within a wide load range.  相似文献   

9.
作者研究发的太阳能-空气双源热泵热水系统,将太阳能热泵与水蓄热结合,根据用户的需要和室外气象条件的变化,具有单独太阳能制热水、单独空气源制热水、制热水兼制冷、单独制冷、供暖等多种功能,可以节约能源,减少环境污染,是绿色建筑值得推广的一项技术。该系统运行稳定,能效比高,不但可以作为一项新技术在实际工程上推广,而且能够进行科研实验,又可供学生进行系统的测试、调试,作为教学仪器使用。  相似文献   

10.
文章针对节能减排的当前形势,通过对在扬州某建筑中的土壤源热泵经济性及节能性进行的分析,提出了地源热泵使用的可行性。  相似文献   

11.
分析了换热器对集热器效率的影响,确定了换热器对集热器的削弱因子;提出了二次换热平板型太阳热水系统的能量方程。对自然循环二次换热平板型太阳热水系统系统的热性能进行了测试与分析,测试表明,自然循环二次换热平板型太阳热水器的平均日效率低于普通平板型太阳热水器,但高于真空管太阳热水器。  相似文献   

12.
本文针对唐山市某示范工程中应用的太阳能-空气源热泵-锅炉供热联合使用技术进行阐述,分析了三者联合运行的技术可行性,强调了可再生能源综合利用的必要性。  相似文献   

13.
为适应学科发展和培养创新人才的需要,设计了一套热管式太阳能与地源热泵耦合系统。详细介绍了系统的基本组成、特点和原理。该系统功能全面、开放性强,能满足创新探索型实验教学的需要,为大学生创新训练计划、研究生培养和教师课题研究等提供高水平研究平台。  相似文献   

14.
An air source heat pump system (ASHPS) used in an office building is set up and studied experimentally. Its operating performance in winter is evaluated based on test data and a comparative discussion is given on the effect of climate conditions and heating load ratio on the operation behavior. Then heating capacity variation caused by evaporator frosting is analyzed as well. Finally, the defrosting parameters and the technical feasibility are studied for a constant heating demand. The experimental results indicate that both the outlet water temperature drop and the system COP should be taken into account when setting defrosting parameters, and ASHPS is a viable technology for space heating and hot-water production in winter in Tianjin, which can maintain the room temperature above 19 ℃ when the outdoor temperature is -2 ℃.  相似文献   

15.
中建立太阳能驱劝的埃里克森热机系统的一般循环模型,探讨回热损失的内不可逆性因素对其循环效率和集热器最佳工作温度的影响,导出系统的最大效率和太阳能集热器的最佳工作温度,所得的结论对此类循环的研究提供新的理论依据。  相似文献   

16.
热泵热水器是一种新型的供热设备,是一种可替代锅炉的供暖设备和热水装置。它通过制冷剂温差吸热和压缩机压缩制热后,与水换热,从而提高了热效率并且能较充分利用能源。热泵热水器必须拥有完善而可靠的控制系统。热泵热水器的控制系统由触摸屏与PLC构成。根据对热泵热水器工作原理、系统控制要求及硬件环境设计了触摸屏界面及PLC控制程序。  相似文献   

17.
为深入了解HFC125跨临界循环热泵热水器的运行特性,设计和建造了一个直流变频热泵热水器实验装置,对HFC125跨临界循环热泵热水器性能进行了实验研究,发现压缩机运行在95Hz时系统存在一个COP峰值.然后以95Hz为例,研究了系统COP与压缩机频率、冷凝压力、蒸发压力、冷却水温升、压缩机排气温度等参数的关系,并与R410A亚临界循环系统性能进行了比较.结果表明:系统存在一最优频率,此时系统有较好的COP值,系统COP随冷凝压力和压比的降低呈上升趋势,而蒸发压力基本恒定;当冷却水温升超过47.5℃时,COP迅速下降.相对R410A亚临界循环,HFC125跨临界循环系统COP显著提升,提高幅度平均在12%以上.  相似文献   

18.
It is promising to simultaneously develop multiple products through the combined utilization of sea-water by solar chimney technology. A small scale experimental system was set up. The collector temperature, the seawater temperature, and the temperature and humidity of the airflow under the collector were measured. Thermal network analysis of the system was carried out. The results show that the airflow is nearly saturated at the entrance of the chimney, and the mean dry-bulb and wet-bulb temperatures of the airflow have increased by 8.4℃ and 9.6℃ respectively. The radiation heat transfer between the collector and the sky is the biggest heat loss in the system, which is up to 29.1% on average of the solar energy. However, the water evaporation heat is about 23.6% on average of the solar energy. To reduce the heat loss and enhance the water evaporation, it is necessary to reduce the emissivity and thermal conductivity of the collector and increase the evaporation areas.  相似文献   

19.
为建立空气源热泵热水器COP随室外环境温度和水箱温度变化的动态模型,先测定了某一空气源热泵热水器随环境温度和水温变化的COP,引入了卡诺因子,得出了COP的拟合公式,并与测试数据进行了对比,对比表明COP的拟合公式精确度较高,能够满足实际工程应用需要。同时.为使该拟合公式对不同性能的空气源热泵热水器具有普适性,在上述公式的基础上引入COP修正系数,得出了适合不同性能空气源热泵热水器COP的拟合公式.经实验对比.表明该公式也能较好的满足实际工程应用需要。  相似文献   

20.
本文介绍了大连长兴岛高尔夫球场会所的水源热泵系统设计,分析了水源热泵系统在夏季、过渡季、冬季的应用,并计算了各个季节水源热泵的cop值,并定性分析了其它空调、采暖的冷热源方式,得出结论,水源热泵系统是节能、环保、安全的冷热源形式,利用了可再生能源,值得推广.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号