共查询到20条相似文献,搜索用时 578 毫秒
1.
《可再生能源》2021,(8)
文章以平板型集热器作为驱动热源,构建了一套额定制冷功率为17.6 kW的小型太阳能吸收式制冷系统,并基于TRNSYS软件构建了小型太阳能吸收式制冷系统模型,研究了太阳辐射强度、集热器面积和蓄热水箱体积的变化对系统运行性能和制冷功率的影响。模拟结果表明:在系统运行过程中,平板型集热器的工作温度约为90℃,单效吸收式制冷机的驱动温度为72.5~95℃,单效吸收式制冷机的最大制冷效率可以达到0.85,由此可知,当热源温度与驱动温度的匹配度较好时,既能保证单效吸收式制冷机的高效运行,又能减少能源品位的浪费;白天,当小型太阳能吸收式制冷系统运行时,系统的太阳能保证率为57.5%,一次能源节约系数可达到0.25,此时,小型太阳能吸收式制冷系统的制冷性能优于电压缩制冷系统。 相似文献
2.
3.
4.
5.
6.
7.
8.
介绍太阳能集热器和氨水吸收式制冷机的结构、原理和特点,对利用太阳能驱动氨-水吸收式制冷空调的可行性进行分析探讨,阐述研制开发太阳能氨水吸收式制冷空调对节能降耗保护环境的意义. 相似文献
9.
提出一种用于住宅采暖和全年提供生活热水的太阳能辅助CO2热泵供热系统,并将该系统运用于上海地区一座90 m2的示范住宅。其中,真空管集热器阵列的面积为40 m2,CO2热泵压缩机的额定功率为2 k W。通过冬季试验对系统进行性能测试。并在此基础上,运用TRNSYS软件建立系统模型,对包括蓄热水箱容积和工作水箱容积等系统的结构参数进行优化分析。结果表明:在环境温度为4.8℃、机组进出口水温37.9℃和48.6℃的实验工况下,CO2热泵机组的COP可达2.63,CO2热泵单独供热模式的系统性能系数COPS可达2.24;在该文实验工况下,太阳能采暖模式的系统性能系数COPS为14.53;当蓄热水箱和工作水箱的容积分别为0.9 m3和0.7 m3时,系统在整个采暖季的耗电量最小且太阳能的保证率达到65.7%。 相似文献
10.
11.
《Applied Thermal Engineering》2014,62(2):424-432
Large scale heat-driven absorption cooling systems are available in the marketplace for industrial applications but the concept of a solar driven absorption chiller for air-conditioning applications is relatively new. Absorption chillers have a lower efficiency than compression refrigeration systems, when used for small scale applications and this restrains the absorption cooling system from air conditioning applications in residential buildings. The potential of a solar driven ammonia–water absorption chiller for residential air conditioning application is discussed and analyzed in this paper. A thermodynamic model has been developed based on a 10 kW air cooled ammonia–water absorption chiller driven by solar thermal energy. Both energy and exergy analyses have been conducted to evaluate the performance of this residential scale cooling system. The analyses uncovered that the absorber is where the most exergy loss occurs (63%) followed by the generator (13%) and the condenser (11%). Furthermore, the exergy loss of the condenser and absorber greatly increase with temperature, the generator less so, and the exergy loss in the evaporator is the least sensitive to increasing temperature. 相似文献
12.
Contribution to the Study of the Reduction of Energy Consumption through the Exchanger Coupled Conventional Air‐Ground‐Air Conditioner. Application to the Building 下载免费PDF全文
In this study, a new method of using the earth‐air heat exchangers to reduce energy consumption in buildings is discussed. The idea is to couple the EAHE with the condenser of a residential air conditioning system to enhance the effectiveness of the latter. Under the climatic conditions of high temperature in summer (south‐eastern region of Algeria), which can sometimes exceed 50 °C, what makes the heat exchange between the air conditioner and the external environment very difficult in addition to the problem of thermal comfort and the cost of energy consumption. Conducting a simulation by the TRNSYS software that allows to couple the model of the EAHE with the condenser of a residential air conditioner and connect the system with a building. The results show a clear reduction in the energy consumed by this system in connection with the direct use of the air conditioner and increase air conditioning efficiency, coefficient of performance, and energy efficiency rating. In this paper the Hollmuller model was ameliorated and the obtained results are in concord with it. The system is capable of resolving the problem of mal cooling of buildings by air conditioners under critical climate conditions, in addition to lowering the heat output of the condenser, and reducing its effect on the environment. 相似文献
13.
建筑形式对太阳能热利用的影响研究 总被引:1,自引:0,他引:1
以上海地区的住宅建筑为研究对象,通过模拟分析的方法,采用DeST软件计算确定建筑逐时的采暖、空调能耗,研究分析窗墙比对建筑全年采暖能耗、全年空调能耗以及全年采暖、空调总能耗的影响规律,研究分析太阳辐射热增加所导致采暖能耗的降低幅度与外围护结构保温性能两者之间的定量关系。计算结果表示在夏季外窗遮阳和夜间通风的条件下,加大南向窗墙比可增强太阳能的热利用效率,降低建筑全年的采暖、空调总能耗;而外围护结构保温性能的增强则可降低室内向室外散热的程度,相应提高对冬季太阳辐射的热利用程度,从而达到降低采暖能耗的目的。 相似文献
14.
外墙保温技术对空调负荷的影响 总被引:8,自引:0,他引:8
采用建筑热环境模拟工具DeST对同一住宅建筑进行模拟计算,分析了不同气候地区外墙保温形式及保温层厚度对空调负荷的影响,并讨论了空调运行模式及自然通风模式的影响,可为不同气候地区的住宅建筑外墙隔热保温设计提供依据。 相似文献
15.
16.
Solar energy is an alternative energy source for cooling systems where electricity is demand or expensive. Many solar assisted cooling systems have been installed in different countries for domestic purpose. Many researches are going on to achieve economical and efficient thermal systems when compared with conventional systems. This paper reviews the past efforts of solar assisted-single effect vapour absorption cooling system using LiBr–H2O mixture for residential buildings. Solar assisted single-effect absorption cooling systems were capable of working in the driving temperature range of 70–100 °C. In this system LiBr–H2O are the major working pairs and has a higher COP than any other working fluids. Besides the review of the past theoretical and experimental investigations of solar single effect absorption cooling systems, some new ideas were introduced to minimize the capital and operational cost, to reduce heat loss from generator and thus to increase COP to get effective cooling. 相似文献
17.
Numerical simulation and performance assessment of a low capacity solar assisted absorption heat pump coupled with a sub-floor system 总被引:4,自引:1,他引:4
A prototype low capacity (10 kW) single stage Li–Br absorption heat pump (AHP), suitable for residential and small building applications has been developed as a collaborative result between various European research institutes and industries. The primary heat source for the AHP is supplied from flat plate solar collectors and the hot/chilled water from the unit is delivered to a floor heating/cooling system. In this paper we present the simulation results and an overview of the performance assessment of the complete system. The calculations were performed for two building types (high and low thermal mass), three climatic conditions, with different types of solar collectors and hot water storage tank sizes and different control systems for the operation of the installation. The simulations were performed using the thermal simulation code TRNSYS. The estimated energy savings against a conventional cooling system using a compression type heat pump was found to be in the range of 20–27%. 相似文献
18.
在环境温度和太阳辐射动态变化的情况下,对制冷量为5 kW的风冷式太阳能吸收式制冷机的性能进行了模拟,得出了集热器出口水温和热水储槽温度随时间变化的规律曲线以及在此规律的影响下吸收式制冷机的性能曲线.模拟结果表明风冷式太阳能吸收式制冷机在理论上是切实可行的,但是环境温度的变化以及风冷系统的散热能力对系统性能有较大的影响,环境温度的升高会使需要风冷降温的冷凝器、吸收器温度升高,从而提高了发生温度的要求,这不利于太阳能的利用和系统的制冷.为此需要强化冷凝器和吸收器的散热效果,来降低境温度对系统的不利影响. 相似文献
19.
Ali R. El‐Ghalban 《国际能源研究杂志》2002,26(9):825-835
The concept of solar cooling is appealing because the cooling load is in phase with the intensity of solar energy. Many system arrangements or cycles are employed to achieve solar cooling, such as Absorption, desiccant or Rankine‐vapour compression systems. The technical feasibility of driving an absorption‐cooling unit by a low‐temperature heat source (such as solar energy using a simple flat‐plate collector) for air‐conditioning applications is investigated in this work. This study aims to design and construct a prototype for an intermittent absorption refrigeration system and to examine its implementation. The operating characteristics of the considered unit are extensively investigated. In order to accomplish this strategy, the prototype was integrated in a test rig designed for this purpose and equipped with the necessary measuring instruments to determine the required operating criteria of the unit. The energy added or extracted to or from the different unit components is calculated and the system performance is analysed. The C.O.P of the unit is found to be 19% which is 2% lower than the designed value, which could be regarded as an encouraging result for more studies in this field. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
20.
In this paper, a solar hybrid desiccant air conditioning system, which combines the technologies of two-stage desiccant cooling (TSDC) and air-source vapor compression air-conditioning (VAC) together, has been configured, experimentally investigated and theoretically analyzed. The system mainly includes a TSDC unit with design cooling capacity for 10 kW, an air-source VAC unit with 20 kW in nominal cooling capacity, a flat plate solar collector array for 90 m2, a hot water storage tank and a cooling tower. Performance model of the system has been created in TRNSYS simulation studio. The objective of this paper is to report the test result of the solar hybrid air conditioning system and evaluate the energy saving potential, thereby providing useful data for practical application. Experimental results show that, under typical weather condition, the solar driven desiccant cooling unit can achieve an average cooling capacity of 10.9 kW, which contributes 35.7% of the cooling capacity provided by the hybrid system. Corresponding average thermal COP is over 1.0, electric COP is up to 11.48. Under Beijing (temperate), Shanghai (humid) and Hong Kong (extreme humid) weather conditions, the solar TSDC unit can remove about 57%, 69% and 55% of the seasonal moisture load, thereby reducing electric power consumption by about 31%, 34% and 22%, respectively. These suggest that the solar hybrid system is feasible for a wide range of operating conditions. 相似文献