建环毕业外文翻译(共14页).doc

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1、精选优质文档-倾情为你奉上 毕业设计（论文）译文题目名称：太阳能空调的近期动态学院名称：能源与环境学院班 级：学 号：学生姓名： 指导教师： 2011年 03 月18日专心-专注-专业太阳能空调的近期动态摘要本文介绍了一些最近欧洲和国际项目的有关太阳能空调的概述（A / C）。该文第一部分显示的结果来自于最近欧洲完成的一项有关10千瓦（约3吨）小的带有地板采暖和制冷系统的原型太阳能辅助吸收热泵的研究和生产。第二部分回顾了一项有关节能潜力和成本绩效的欧洲项目目前的动向来执行欧洲的比较研究和国家的RD以及证实了太阳能空调的成效，来促进其未来的增长和市场一体化和确定未来的需要。第三部分回顾了由国际能

2、源机构（国际能源署）支持的建筑物太阳能辅助空调项目目前的动向。引言能源消耗在商业和民用建筑中约占欧洲40的能源预算（欧共体2000年）。这是为了满足建筑物的供暖，空调，灯光，以及其他电器用具和设备的能源需求。总的来说，在南欧的大型空调建筑物当中供冷占主要地位。常规使用的制冷设备带来了加重电力负荷和增加电能消耗的一些缺点，并且由于制冷剂的使用和发电导致了环境问题。南欧国家的夏季是炎热和潮湿的天气。在过去的几十年当中，由于生活条件，室内居住环境和工作条件的改善，常规空调的销售飞速增加。据市希腊商务部市场调查的结果显示，在希腊每年的5月至8月期间约占空调销售额的95，并且约达20万台（主要是小型分体

3、式热泵）每年。在夏季空调的使用导致了用电高峰，并且定期导致了维持整个国家电力系统稳定的如雅典等大城市大面积的电力短缺。例如，最近发生的事件是在2000年7月初14:00时的热浪，其负荷高峰达到8250兆瓦（28.109英热单位/小时）。在西班牙（佩雷拉等人，1995年），空调对电能的需求超过10万千瓦（34.109英热单位/小时）。其实，在南欧国家的中小型市场，在夏季电力需求峰值的增长和空调销售的增长之间有一个完善的连接。事实上，在夏季冷量需求的高峰和太阳能能源的高可用性相关联，并且为能够与冷却技（即吸收和干燥剂冷却）相匹配的太阳能热技术的开发提供了一个机会。单效和双效的吸收式制冷系统已被证实

4、并且销售技术和生产厂商主要分布在美国和日本。大型的单效机组的COP值大概在0.7到0.8之间。为了提高性能，可采用双效吸收式制冷机组，其COP值接近1.0。在美国和日本目前的研究集中于三，四效系统，它在改进制冷系统时COP值达到1.7到2.2（李和谢里夫1999年;毛额男子等 1995年），呈现出了引人注目的潜力，甚至达到热效率等于目前这些最好的电制冷机。近年来创新蒸气吸收式循环和工作液已经被广泛研究，如吴记录和埃姆斯（2000年）。 一个吸收式热泵法（AHP）可同时用于加热和冷却生产并且能够进行热经营，其通常以热水或蒸汽作为能源来源。基本的吸收式制冷剂是在大约1777年形成的。冷却是通过吸收

5、机组进行的。在基本的（单效）吸收式制冷循环中，仍处于低压状态的制冷剂蒸汽转化为液体相（溶液）。制冷剂蒸汽被第二种液体吸收（吸收剂），从而使转换成为可能。吸收过称的进行是由于互溶的物质有能够相混合的倾向，并且由于制冷剂和吸收剂分子之间有相似的性质。这种能量源于热凝结，感热和稀释热。该制冷剂和吸收剂溶液在液泵中加压并且通过发电机使制冷剂和吸收剂分离（用再生蒸馏过程），最终通过热交换器进行换热。与热泵相匹配的吸收式制冷剂通常是水溴化锂或氨水。溴化锂制冷剂的优点包括高安全性，高波动率，高亲和力，高稳定性，高潜热（多根等人。1995年; Machielsen 1990年Alefeld和齐格勒1985;格

6、罗斯曼和Perez -布兰科1982年）。吸收式热泵原料的选择来源广泛，包括太阳能加热热水，煤气直接燃烧，废热，热电联产热，等等，其温度通常高于171 C。吸收制冷循环是在发电机中开始的，其工作起来像一个机组（见暖通空调2002年， 41章）。所提供的热使制冷剂蒸发，使其与水脱离流向吸收装置。由于热效应所产生的压力推动热的制冷剂蒸汽流向空气冷凝器或水冷凝器，在冷凝器中由于压力的作用使其冷却或液化。液态的制冷剂流向蒸发器，在蒸发器中水中所包含的热量从空调区域中被除去。这些热量导致液态的制冷剂蒸发并且制冷剂蒸汽流向吸收装置。在吸收装置中，制冷剂蒸气和从发生器中回来的溶液相接触，并且制冷剂和溶液的混

7、合液通过热交换器的另一部分来完成把进入水溶液中的制冷剂吸收回来。处理之后的溶液被压入发生器，以此进行连续的制冷操作。太阳能辅助冷却系统通常和与热驱动冷却设备相连接的太阳热能收集器相耦合。它们包括4个（图1）主要组成部分，即：太阳能储存系统，其中可能包括一个热缓冲储存；冷却装置；空气调节系统；及辅助子系统。辅助子系统在原则上整个系统可能在不同的地方相综合。图1 太阳能辅助空调系统的各个组成部分 系统布局整个系统的布局如图2它包括：（1）太阳能系统（收集器和储存罐），（2）辅助加热器;（3）吸收式热泵;（4）楼层的加热/冷却系统（5）控制器。 图2 与太阳能辅助吸收热泵相耦合的地板加热/冷却系统的

8、布局 对于整个系统的仿真，有关地板采暖/制冷系统的控制基于户外/室内的空气温度，以保持建筑物内部的温度在热舒适区（25-26 C或77至79 F）之间。每个时间段，冷冻水都提供与建筑物逐时冷负荷相适应的供水温度。当室内空气温度高于25（77 F）时，将给地面系统提供冷冻水。水流量和室内温度是相关联的，以免地板上有凝结水析出（即地面温度不能低于室内空气的露点温度低）。地板冷却系统的热交换系数在试验中用一个函数的几个参数来衡量（即供水温度，室外温度，水流量，地板材料，空气更新率）。测量值的平均值为7.1瓦/（平方米.K）或1.25仟卡/（平方英尺.）（奥利森等,2000年）。附加试验也用于研究不同

9、负载情况下的地板冷却系统，包括突然增加的室外温度和湿度，以及室内负载的增加。根据研究结果显示，这个系统能够成功避免冷凝问题的出现。 技术，市场方面和环境效益冻水以一项有关市场上现有的太阳能辅助空调设备的调查致力于在以吸收和吸收冷及转轮和制度为重点的方面达成一个现成的概述。一项有关已完成的和正在进行的国家研究和开发新组件的调查正在进行当中。其目的是为太阳能辅助空调系统找到可行的有前途的新方法。一个涉及能源，金融，和环境组织的对于整个系统运行状况的共同认定的方法已经产生，并且将在设计的初期阶段为不同系统的选择提供一个简单的方法。这项工作的主要目的是为建筑师，建筑工程师和规划师，设施管理人员，及有兴

10、趣的业主提供一个注册的“太阳能冷却手册”。太阳能辅助冷却示范工程在10个国家一共有14示范系统将进行调查，其中包括8个新工厂和6个现有的装置。其目标是：（1）在实际项目中用太阳能辅助冷却系统获得实际经验（2）得出仿真系统的验证性数据（3）研究设计和控制方面系统的适应性（四）得出太阳能辅助冷却系统整个运行工况中的真实数据（5）支持市场引进的技术。数据监测工作将在不同层面进行。首要的是基于整个系统评估下的每日能源平衡的全球性的检测。第二是基于研究单个组件的运行工况下所有重要参数一分钟的平均值的详细的检测活动。调试和七个示范项目的监测工作在4个国家中已经开始进行了。国际能源机构25项工作的主要成果将

11、是：（1）太阳能辅助空调手册（包括对元件和系统的描述，操作和控制的问题，设计准则），（2）有关太阳能辅助空调示范项目的书籍（包括技术设计和性能数据）（3）基于计算机的设计工具。结论最近完成的SOLHEATCOOL研究项目已经证明，无论是通过实验还是模拟，一个提供地板采暖/冷却系统的10千瓦（约3吨）小的太阳能辅助单级吸收式热泵的可行性已经被证实。在测试过程中，试运行的热泵达到的冷量为6至10千瓦（2至3吨），性能系数COP达到了0.7。在此设备商品化之前必须对设备进行进一步的改善。与传统的冷却装置使用的压缩类型热泵相比，估计能源节约范围在20和27之间。根据不同的地域，使用太阳能收集器来驱动热

12、泵的简单的投资回收期估计约为5-9年，而传统的冷却装置使用的压缩式热泵整个系统的投资回收期为6.5至14年。灵敏度的模拟结果分析表明：很难为最佳系统设计界定出一个单一的答案。原因就在于其依赖于一系列重要的参数，其中相当数量体现了一个精心设计方案的必要性。在系统开发中的额外优势中冬季取暖可提高其经济可行性。此外为了促进市场一体化和减少在建筑物中使用太阳能辅助空调的能耗，RD活动是必要的。在最近的两个项目中，意大利外贸保险服务和国际能源机构的工作，预计将有助于确定研发重点，并提供实用用户指南，工具和技术指引，以鼓励这些技术的未来应用前景。太阳能空调在能源节约方面有强大潜力。特别是南欧和地中海地区，

13、太阳能辅助冷却系统可节约40至50（或0.02欧元每千瓦小时的最有前途的技术）的初级能源，并在15年或更短的时间范围内就能够得到投资回报。Recent Activities on Solar Air ConditioningABSTRACT This paper presents an overview of some recent European and international projects on solar air conditioning (A/C). The first part reviews the results from a recently completed Eu

14、ropean research project on the study and manufacturing of a small 10 kW (about 3 ton) prototype solar-assisted absorption heat pump coupled with a floor heating and cooling system. The second part reviews the current activities in a European project to perform a comparative study of European and nat

15、ional R&D and demonstration activities on solar A/C, in terms of energy-saving potential and cost performance, to promote their future growth and market integration and to identify future needs. The third part reviews the current activities in a project supported by the International Energy Agency (

16、IEA) on solar-assisted air conditioning of buildings. INTRODUCTION Energy consumption in commercial and residential buildings represents approximately 40% of Europes energy budget (EC 2000). This is allocated for satisfying the buildings energy needs for heating, air conditioning, lighting, and the

17、other electrical appliances and equipment. For southern Europe and for large air-conditioned buildings in general, cooling is of primary concern. The use of conventional cooling equipment has introduced several drawbacks, including peak electric loads and increased electrical energy consumption, and

18、 has caused environmental problems resulting from the use of refrigerants and electric power generation. Southern European countries exhibit hot and humid weather conditions in summer. Sales of conventional air-conditioning units have been growing fast over the last couple of decades as a result of

19、an increase of living standards and the need for improved indoor living and working conditions. According to market surveys by the Hellenic Ministry of Commerce, about 95% of air-conditioning sales in Greece occur in the period of May-August and reach about 200,000 units (primarily small split-type

20、heat pumps) every year. The use of air-conditioning units in summer causes peak electric loads that periodically result in power shortages in large areas of metropolitan cities, such as Athens, in order to maintain the stability of the national power system. For example, the most recent event was du

21、ring the heat wave at the beginning of July 2000 at 14:00, when the peak load reached 8250 MW (28.109 Btu/h). In Spain (Pereira et al. 1995), the power demand for air conditioning exceeds 10 GW (34.109 Btu/h). Actually, in south European countries, there is a well-established connection between the

22、growth of peak power electricity demand in summer and the growth of air-conditioning sales in the small-and medium-sized market. The fact that peak cooling demand in the summer is associated with high solar energy availability offers an opportunity to exploit solar thermal technologies that can matc

23、h cooling technologies (i.e., absorption and desiccant cooling). Single-and double-effect absorption cooling systems are proven and marketable technologies and are primarily manufactured in the United States and Japan. Typical COPs for large single-effect machines are 0.7 to 0.8. For improved perfor

24、mance, double-effect absorption systems are currently available, with typical operating COPs close to 1.0. Current research in the U.S. and Japan concentrates on three- and four-effect systems, which present an attractive potential for improved cooling performance, with a COP of 1.7 to 2.2 (Lee and

25、Sherif 1999; Gross-man et al. 1995) and even reach thermal efficiencies equal to those of the best currently available electrical chillers. Innovative vapor absorption cycles and working fluids have been extensively researched in recent years, as documented in Wu and Eames (2000). An absorption heat

26、 pump (AHP) can be used for both heating and cooling production and it is heat operated,typically using hot water or steam as the energy source. The fundamentals of absorption refrigeration were formulated in about 1777. Cooling is produced by the absorption unit. In the basic (single-effect) absorp

27、tion cycle, low-pressure refrigerant vapor is converted to a liquid phase (solution) while still at low pressure. Conversion is made possible by the vapor being absorbed by a secondary fluidthe absorbent. Absorption proceeds because of the mixing tendency of miscible substances and because of an aff

28、inity between absorbent and refrigerant molecules. This energy arises from the heat of condensation, sensible heat, and heat of dilution. The refrigerant-absorbent solution is pressurized in the solution pump and conveyed by a heat exchanger to the generator where refrigerant and absorbent are separ

29、ated (regenerated by a distillation process). The refrigerant-absorbent pair used with an AHP is usually water-lithium bromide or ammonia-water. Advantages of the water-lithium bromide pair include high safety, high volatility ratio, high affinity, high stability, and high latent heat (Dorgan et al.

30、 1995; Machielsen 1990; Alefeld and Ziegler 1985; Grossman and Perez-Blanco 1982). Absorption heat pumps offer fuel choice flexibility, including solar-heated hot water, direct gas firing, waste heat, cogeneration heat, etc., usually at a temperature higher than 171C. The absorption cooling cycle be

31、gins in the generator, which works like a precolator (see ASHRAE 2002, chapter 41). The supplied heat vaporizes the refrigerant, leaving behind a weak solution in water, which flows to the absorber. Pressure, generated by heating, pushes the hot refrigerant vapor to an air-or water-cooled condenser,

32、 where it is cooled and liquefies under pressure. The liquid refrigerant flows to the evaporator, where it cools water containing heat removed from the conditioned space. This heat causes the refrigerant liquid to vaporize and the vapor then flows to the absorber. In the absorber, the refrigerant va

33、por is contacted with weak solution returning from the generator, and the refrigerant/weak solution mixture is passed through another section of the cooled heat exchanger to complete the absorption of the refrigerant back into solution in water. The strong solution is then pumped back to the generat

34、or, thus giving continuous chilling operation. Solar-assisted cooling systems are usually coupled to solar thermal collectors connected to thermal-driven cooling devices. They consist of four main components (Figure 1), namely: the solar system, which may include a heat buffer storage; cooling devic

35、e; air-conditioning system; and auxiliary subsystem. The auxiliary subsystem may, in principle, be integrated at different places in the overall system. Figure 1 Variety of systems for solar-assisted air conditioning. System Layout The overall system layout is illustrated in Figure 2 and includes: (

36、1) the solar system (collectors and storage tank); (2) an auxiliary heater; (3) the absorption heat pump; (4) a floor heating/cooling system; and (5) controllers. Figure 2 System layout of the floor heating/cooling system coupled to a solar-assisted absorption heat pump. For the simulations of the e

37、ntire system, the control of the floor heating/cooling system was based on the outdoor/indoor air temperatures, in order to keep the building within the thermal comfort zone (25-26C or 77-79F). For each hourly time step, the chilled water supply temperature was regulated to meet the buildings coolin

38、g load. The chilled water was supplied to the floor system when the indoor air temperature is higher than 25C (77F). The water flow rate and temperature were regulated in order to avoid floor condensation (the floor temperature cannot be lower than the dew point temperature). The heat exchange coeff

39、icient of the floor cooling system was experimentally measured as a function of several parameters (i.e., water supply temperature, outside temperature, water flow, floor covering material, and air renewal rate). The average measured value was 7.1 W/(m2 . K) or 1.25 Btu/ (ft2 .F) (Olesen et al. 2000

40、). Additional experiments were also used to study the behavior of a floor cooling system under different load scenarios, including fast increase in outdoor air temperature and humidity and sudden increase in internal loads. According to the results, the proposed system demonstrated that it can succe

41、ssfully react to avoid condensation problems. Technology,Market Aspects and Environmental BenefitsA survey of market available equipment for solar-assisted air conditioning aims to achieve an overview of readily available components, with an emphasis on absorption and adsorption chillers, and desicc

42、ant wheels and systems. A survey of completed and ongoing national research and development work on new components is also in progress. The aim is to identify promising new approaches that are feasible for solar-assisted A/C systems. A common agreed method to assess overall system performance relate

43、d to energy, financial, and environmental issues has been derived and will be incorporated in the design tool to provide an easy method for comparing different system options during the predesign phase. The main outputs of this work will be incorporated in a “Solar Cooling Handbook” that will be pre

44、pared for architects, building engineers and planners, facility managers, and interested building owners. Solar-Assisted Cooling Demonstration Projects A total of 14 demonstration systems in 10 countries will be investigated, including 8 new plants and 6 existing installations. The objectives are: (

45、1) to achieve practical experience with solar-assisted cooling in real projects and with this (2) to yield data for the validation of the simulation tools, (3) to study the suitability of the design and control concepts, (4) to obtain reliable results about the overall performance of solar-assisted

46、cooling, and (5) to support market introduction of the technology. Data monitoring will be performed at different levels. The first one will be a global monitoring, based on daily energy balances that allows overall system assessment. The second one will be a detailed monitoring campaign, based on o

47、ne-minute averages of all important parameters, that allows study of the performance of single components. Commissioning and monitoring of seven demonstration projects in four countries have already started. The main deliverables of the IEA Task 25 work will be: (1) a handbook for solar-assisted air

48、 conditioning (including component and system description, operation and control issues, design guidelines); (2) a book on solar-assisted air-conditioning demonstration projects (including technical design and performance data); (3) computer-based design tools. CONCLUSIONS The recently completed SOLHEATCOOL research project has demonstrated, both by experiments and simulations, the feasibility of a solar-assisted small 10 kW (about 3 ton) single-stage absorption heat pump that supplies a floor heating/cooling system. During testing, the prototype AHP achieved a cooling power