外文翻译--太阳能空调系统综述_有太阳能空调吗

翻译原文 A Review on Solar Powered Air Conditioning System Ravi Gugulothu, Naga Sarada Somanchi, Hima Bindu Banoth and Kishan Banothu Abstract The twenty first century is rapidly becoming the perfect energy storm, modern society is faced with volatile energy prices and growing environmental concerns as well as energy supply and security issues. One of the greatest challenges facing mankind in the twenty first century is energy. Fossil fuels such as coal, petroleum and natural gas have been the main energy resources for everything vital for human society. The burning of fossil fuels has caused and is causing damage to the environment of earth. By 2050 the demand for energy could double or even triple as the global population grows and developing countries expand their economies. This has already raised concerns over potential supply difficulties, depletion of energy resources and expediting environmental impacts like ozone layer depletion, global warming and climate change etc. The most abundant energy resource available to human society is solar energy. The utilization of solar energy is as old as human history. Among various types of renewable energy resources, solar energy is the least utilized. Air conditioning is essential for maintaining thermal comfort in indoor environments, particularly for hot and humid climates. Today, air conditioning comprising cooling and dehumidification has become a necessity in commercial and residential buildings and industrial processes. During the summer, the demand for electricity greatly increases because of the extensive use of air-conditioning systems. This is a source of major problems in the country’s electricity supply and contributes to an increase of CO2 emissions causing the environmental pollution and global warming. On the other hand, vapour compression air conditioning systems have impacts on stratospheric ozone depletion because of the chlorofluorocarbons (CFC) and the hydro fluorocarbon (HCFC) refrigerants. The use of solar energy to drive cooling cycles is attractive since the cooling load is roughly in phase with solar energy availability. To cool with solar thermal energy, one solution is to use an absorption chillier using water and lithium bromide solution. Solar air conditioning systems help to minimize fossil fuel energy use. Among the evolving energy efficient air conditioning technologies are liquid desiccant air conditioning (LDAC) systems, which have showed promising performance during the past decades and are believed to be a strong competitor with the widely used conventional air conditioning systems (CAC). Desiccant evaporation cooling technology is environmental friendly and can be used to condition the indoor environment of buildings. Unlike conventional air conditioning systems, the desiccant air conditioning systems can be driven by low grade heat sources such as solar energy and industrial waste heat. In this study, a focus is made on reduction in Air Conditioning capacity, fuel savings and emission reductions attainable through the use of solar energy. Keywords:SolarEnergy, Desiccant Air ConditioningSystem, Humidification and. Dehumidification, Conventional Air Conditioning; 1. Introduction As a kind of renewable energy, solar energy is paid more and more attention in the world. Solar system can be classified into two categories; those are thermal systems which convert solar energy to thermal energy and photovoltaic systems which convert solar energy to electrical energy. However, more solar radiation which falling on photovoltaic cells is not converted to electricity, but either reflected or converted to thermal energy. This method leads to a drop of electricity conversion efficiency due to an increase in the photovoltaic cells working temperature. In the past century, scientific community has devoted much effort to procure energy sustainability of housing in two main directions; those are reducing external energy supply and using renewable energy for the remaining. In both ways, solar resources are gaining popularity because they increase energy independence and sustainability at the same time offering nearly zero impact to the environment. The modern comfort living conditions are achieved at the cost of vast energy resources. Global warming and ozone depletion and the escalating costs of fossil fuels over the last few years to the design and control of building energy systems. Solar energy is abundant and clean, it is meaningful to substitute solar energy for conventional energy. Solar energy therefore has an important role to play in the building energy systems. The increasing scarcity and cost of fossil fuels and incentives to reduce greenhouse gas emissions have led to a growing interest in solar energy. Solar energy is widely affordable and has the capability to meet household demand over the year. Unfortunately, its intermittency and variability with weather conditions, time and seasons lead to a mismatch between heating demand and solar energy availability. Air conditioning systems are installed in buildings to provide the occupants with healthy and productive environments. Considerable amount of energy is consumed in the operation of the widely used energy inefficient conventional air conditioning systems, which leads to several environmental problems that are related to energy production such as air pollution, global warming and acid precipitation. From recent studies, those buildings are responsible for the consumption of around 40% of the primary energy consumption and the emission of nearly 33% of the green house gases in the world. An air conditioning system consists of components and equipment arranged in sequential order to heat or cool, humidify or dehumidify, clean and purify, attenuate objectionable equipment noise, transport the conditioned outdoor air and recirculate air to the conditioned space and control and maintain an indoor or enclosed environment at optimum energy use. Most of the air conditioning systems perform the following functions: a.Provide the cooling and heating energy required b.Condition the supply air, heat or cool, humidify or dehumidify, clean and purify and attenuate any objectionable noise produced by these systems c.Distribute the conditioned air, containing sufficient outdoor air, to the conditioned space. d.Control and maintain the indoor environmental parameters such as temperature, humidity, cleanliness, air movement, sound level and pressure differential between the conditioned space and surrounding within predetermined limits. 1.1. Applications of air conditioning system a.Institutional buildings, such as schools, colleges, universities, libraries, hospitals and nursing homes, museums, indoor stadiums, cinema theatres..…etc. b.Commercial buildings, such as offices, stores and shopping centres, supermarkets,department stores, restaurants and others. c.Residential buildings, including hotels, motels, single family and multifamily low rise buildings of three or fewer stories above grade d.Manufacturing buildings, which manufacture and store products for examples medicines e.The transportation sectors like Automobiles, aircraft, railroad cars, buses and cruising ships.... etc Air conditioning systems are mainly for the occupant’s health and comfort. They are often called comfort air conditioning systems. 1.2. Principle of air conditioning system Figure 1 shows the window mounted air conditioning system. The cabinet is divided into indoor and outdoor compartments which are separated by insulated wall to reduce the heat transfer. The DX coil and indoor fan are in the indoor compartment. The outdoor compartment contains the compressors, condensers, outdoor fan, capillary tube and fan motor. The fan motor often has a double ended shaft which drives both fans at a time. Fig. 1. Window mounted air conditioning Return air from the conditioned space flows through a coarse air filter and is cooled and dehumidified in a DX coil and then enters the inlet of the indoor fan. In a room air conditioner, the indoor fan is a forward curved centrifugal fan. The conditioned air is pressurised in the impeller and forced through the air passage that leads to the supply grille. The conditioned air is then supplied to the conditioned space to offset the space cooling load. Outdoor air is extracted by the propeller fan and forced through the condensing coils, in which hot gaseous refrigerant is condensed to liquid refrigerant. During condensation, condensing heat is released to the outside through the cooling air. A portion of outdoor ventilation air is extracted by the indoor fan and mixed with the return air. The opening of the outdoor ventilation air intake is adjustable. Scientists and engineers are trying to develop more efficient air conditioning systems that are capable of achieving good indoor air quality with low energy consumption rates and air pollution emissions. Among the evolving energy efficient air conditioning technologies are liquid desiccant air conditioning (LDAC) systems, which have showed promising performance during the past decades and are believed to be a strong competitor with the widely used conventional air conditioning systems (CAC). The air handling in air conditioning systems was moist because of the dehumidification process in summer, so bacteria were easily propagated and developed. In addition, the air humidity in moist central air conditioning systems is seldom controlled. This causes people to feel uncomfortable in such air conditioning rooms. Solar energy driven liquid desiccant cooling air conditioning systems (LDCS) can improve indoor air quality and reduce electrical energy consumption and have been regarded highly by researchers and engineers in recent years. The desiccant based air conditioning system comes to be one of the prospective alternatives for the traditional vapour compression air conditioning systems. 1.3. Literature review  Ahmed H Abdel Salam and Carey J Simonson (2014) proposed a membrane liquid desiccant air conditioning (M-LDAC) system modelled using the TRNSYS building energy simulation software. The four air conditioning systems investigated in this study are evaluated from technical, environmental and economic points of views. They found that, the energy consumption of the systems with an ERV increases as the exhaust airflow decreases. Energy consumptions of the CAC-ERV increases by 11% and M-LDAC-ERV increases by 6% when Rexhaust decreases from 1 to 0.6. When M- LDAC system is used CO2 emissions decrease by 19% compared to CAC system and CO2 reduction goes to 31 % when ERV used at Rexhaust equal to unity in the M-LDAC system. It was found that the electrical, thermal and total COPs of the M-LDAC system are 3.45, 1.95 and 0.68 respectively. In their simulation results, the M-LDAC system is a promising system from technical environmental and economic point of views. More energy savings can be achieved through the integration of an energy recovery ventilator, a solar thermal system or a heat pump with the proposed M-LDAC system. Balghouthi M et al (2008) did computer model and simulations using the TRNSYS and EES programs with meteorological data. The system optimized for a typical building of 150 m2 area consists of a water lithium bromide absorption chiller of a capacity of 11 kW, a 30 m2 flat plate collector area tilted 35° from the horizontal and 800 1 hot water storage tank. The simulation results show that, absorption solar air conditioning systems are suitable under Tunisian conditions. Elsherbini A L and Maheshwari G P (2010) they found that the theoretical increase in the coefficient of performance (COP) due to shading is within 2.5%, this small improvement in ideal efficiency decreases at higher ambient temperatures, when enhancements to efficiency are more needed. The actual efficiency improvement due to shading is not expected to exceed 1% and the daily energy savings will be lower. Guo J and Shen H G (2009) studied a lumped method combined with dynamic model and investigated the performance and solar fraction of a solar ejector refrigeration system (SERS) using R134a. They found that, during the office working time, i.e. 9:00 a.m. to 5:00 p.m. the average COP and the average solar fraction of the system were 0.48 and 0.82 when the operating conditions are: generator temperature is 85°C and evaporator temperature is 8°C and condenser temperature varying with ambient temperature. This system can save up to 80% of electrical energy when compared with traditional compressor based air conditioning. Ha Q P and Vakiloroaya V (2014) studied the performance enhancement and energy efficiency improvement of a new hybrid solar assisted air conditioning system. A single stage vapour compression solar air conditioner consists of six major components; a compressor, a condenser, an expansion device, an evaporator, a solar vacuum collector and a solar storage tank. In this new configuration a bypass line is implemented in the discharge line after the compressor to control the refrigerant mass flow rate via a two way valve while a variable speed drive is connected to the air cooled condenser to adjust the condenser fan air flow rate. From the simulation, they found that the enthalpy of refrigerant entering the expansion valve with and without the new configuration is reduced by 8.5%. Designed at steady state conditions, the compressor power consumption for the system without control and the developed system are 1.45kW and 1.24kW and energy savings is 14%. The average power consumption by using the developed system is 9.7% less than that of the uncontrolled system. The average energy saving potential for the proposed approach for the compressor and condenser fan is 7.1% and 2.6%. Both of compressor and condenser reduction can result ultimately in an increase of COP. The average supply temperature of the developed system is decreased from 13.77°C to 11.44°C. The average energy consumption of the newly developed system under control and the original one in summer month power consumption is less than the power usage of the uncontrolled plant. For the closed loop system under control have 7% to 14% electricity consumed by the compressor can be saved using the proposed system under multivariable control as compared to the system without control. They concluded that this new design is promising for improving the system performance while fulfilling the cooling demands as well as achieving high energy efficiency. Ibrahim I El Sharkawy et al (2014) theoretically investigation on the performance of solar powered silica gel/water based adsorption cooling system working under Middle East region climate conditions. Two bed silica gel/water type adsorption chiller has been used. They found that the maximum cyclic average cooling capacity of the system working under Cairo and Jeddah climate conditions reaches to 14.8 kW and 15.8 kW under Aswan climate conditions. Cooling capacity of the system without hot water buffer storage reaches its maximum at noon and for the system with hot water buffer storage, the maximum cooling capacity value is 13 kW that is achieved at a time interval of 14:00 and 15:00 hours. The system with hot water buffer storage has less fluctuating cooling energy production compared to that of the system without hot water buffer storage. Lucas M et al (2003) installed a Hydrosolar roof prototype on a laboratory roof at Spain. This building was air conditioned with a water condensed chiller working with the solar roof as a condenser. The total volume occupied by the four cells of the prototype is roughly 6m*6m*1.2m in size. During the summer 2000 the system was monitored to obtain performance data in a real installation and under real conditions. They created CFD model and analysed. From their numerical results and experimental results, they confirmed that, the air mass flow is induced through the channel due to natural and forced convection. Natural convection is produced by the solar radiation heating the plates and forced convection is due to the wind suction effect at the output of the channel. Therefore, the two main meteorological factors that influence the system performance are solar radiation and wind velocity. Ma Q et al (2006) studied performance of hybrid air conditioning systems and they observed that, the performance of hybride air conditioning system is 44.5% higher than conventional vapour compression refrigeration system at a latent load of 30% and the improvement can be achieved by 73.8% at a latent load of 42%. Min Tu et al (2010) performed comparison between two novel configurations of liquid desiccant air conditioning system driven by low grade thermal energies. Moncef Balghouthi et al (2005) studied with the TRNSYS program simulation study of solar powered absorption cooling technology under Tunisian conditions. A number of simulations were carried out in order to optimize the various factors affecting the performance of the system. Their simulation results show that absorption solar air conditions solar air conditioning systems are suitable for Tunisian’s conditions. Sukamongkol Y et al (2010) they conducted an experimental test to investigate validity of a developed simulation model in predicting the dynamic performance of a condenser heat recovery with a hybrid PV/T air heating collector. The thermal energy generated by the system can produce warm dry air as high as 53°C and 23% relative humidity. 6% of daily electricity can be obtained from the PV/T collector in the system. The use of a hybrid PV/T air heater, incorporated with the heat recovered from the condenser to regenerate the desiccant for dehumidification and save the energy use of the air conditioning system by 18%. They concluded that, the experimental validation results that the developed simulation model is able to predict within acceptable limits of accuracy the performance of a condenser heat recovery with a hybrid PV/T air heater to regenerate desiccant for reducing energy use of an air conditioning room. Thosapon Katejanekam and Kumar S (2008) simulation procedure is used to predict the operating and performance parameters of the system in the form of daily profiles. They found that, the system is reduced the average relative humidity of air is decreased by 15%. The regenerating air coming out of the solar C/R is warmer and drier than the entering ambient air. They studied the system performance with the ventilation air flow rate was varied and they found that, the effectiveness at the ventilation rate of 40, 60 and 80 CFM is decreased by 23%, 45% and 68% when compared with the base 20 CFM. Because, the less contact time between the air and the desiccant inside the dehumidifier. On a daily average, the relative humidity of the delivered air at the ventilation rate of 20, 40, 60 and 80 CFM is 43.12%, 48.49%, 52.83% and 57.15%. This is due to the less moisture removal effectiveness at higher ventilation rates. At the ventilation rate of 40, 60 and 80 CFM, the moisture removal rate is increased by48%, 58% and 26%, whereas the evaporation rate is increased by 17%, 20% and 6%. Tingyao chen et al (2007) designed a solar air conditioning system which is independent on design dry bulb and wet bulb temperatures. This design coincident dry bulb and wet bulb temperatures more than 6°C higher as compared to the newly generated design dry bulb and wet bulb temperature. From this new method they can, when the peak cooling load occurs, HVAC engineers can avoid calculating 24hours cooling loads on one design day in each month of the year. This new method and design weather data allow to determining the peak cooling load for a room or building in any orientation directly, but with a thermal lag less than 1 hour. Yonggao Yin and Xiaosong Zhang (2010) studied on internally heated and adiabatic regenerators in liquid desiccant air conditioning system. Heat and mass transfer model was used to analyse and compare the performance of internally heated and adiabatic regenerators. They found that, internally heated regenerator is proposed to achieve better regeneration performance when compared to conventional packed regenerator. Internally heated regenerator not only could increase the regenerate rate, but also could exhibit higher energy utilization efficiency. Internally heated regenerator can provide comparable regeneration efficiency and regeneration rate at low desiccant flow rate, so it should be a good alternative to avoid carryover of desiccant droplets. Higher air flow rate would result in a deduction of regeneration thermal efficiency although achieving higher regeneration rate. Yonggao Yin et al (2007) experimentally studied the dehumidification rate of the air decreases from 0.104 g/sec to 0.073 g/sec when the temperature of the inlet air changes from 29°C to 34.1°C. From this experiment, they found that the average mass transfer coefficient of the packing regenerator is 4g/m2sec. When the desiccant solution mass concentration is 20% and heating temperature is 77.5°C, the maximum mass transfer coefficient is 7.5 g/m2sec. In this experiment, the humidity of the inlet air is varied from 11.5 g/kg to 35 g/kg and its temperature is 28.5°C. The desiccant solution temperatures are in the range from 55°C to 70°C. The solution outlet temperatures range between 39.5°C to 43°C and the air outlet temperatures range between 32°C to 35°C. They found that the dehumidification rate increases obviously with increasing humidity of the inlet air. The coefficient of performance (COP) of the air conditioning systems varies from 0.7to 1.2. 2. Conclusions From the literature review, it is observed that, the energy and water are the basic necessity for all of us to lead a normal life on this beautiful earth. Solar energy technologies and its usage are very important and useful for the developing and under developed countries to sustain their energy needs. The main motivation for solar cooling systems is the substitution of electricity as the premium energy sources for air conditioning systems by a renewable heat source, i.e. low grade heat from solar collectors. Solar cooling is a good example of addressing climate changes. Long term data should be used to prove the feasibility of air conditioning systems. Acknowledgements Foremost, I am thankful to Professor A.V. Sita Rama Raju, JNT University for his valuable suggestion of reading numerous research publications in the area of solar distillation and to write review papers. I am thankful to Professor K.Vijaya Kumar Reddy and Professor B. Sudheer Prem Kumar, JNT University and my parents for their encouragement in preparing this research paper. References 1. Ahmed H Abdel Salam and Carey J Simonson, Annual evaluation of energy, environmental and economic performances of a membrane liquid desiccant air conditioning system with/without ERV, Applied Energy, 116, pp: 134-148, 2014. 2. 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A Review on Solar Powered Air Conditioning System 太阳能空调系统综述 Ravi Gugulothu，Naga Sarada Somanchi，Hima Bindu Banoth和Kishan Banothu 摘要：二十一世纪正迅速成为完美的能源风暴，现代社会面临着能源价格波动和日益严重的环境问题以及能源供应和安全问题。21世纪人类面临的最大挑战之一是能源。煤、石油、天然气等化石燃料是人类社会一切重要的主要能源。化石燃料的燃烧已经并正在对地球环境造成破坏。到2050年，随着全球人口增长和发展中国家经济扩张，能源需求可能会增加一倍甚至三倍。这已经引起了人们对潜在供应困难、能源资源枯竭和加速臭氧层损耗、全球变暖和气候变化等环境影响的关注。人类社会可利用的最丰富的能源是太阳能。太阳能的利用和人类历史一样古老。在各类可再生能源中，太阳能利用最少。空调对于保持室内环境的热舒适性是必不可少的，特别是对于湿热气候。如今，包括冷却和除湿的空调已经成为商业和住宅建筑以及工业过程中的必要条件。夏季，由于空调系统的广泛使用，电力需求大幅增加。这是该国电力供应出现重大问题的根源，并导致二氧化碳排放量增加，造成环境污染和全球变暖。另一方面，由于含氯氟烃( CFC )和氢氟碳化合物( HCFC )制冷剂的存在，蒸汽压缩空调系统对平流层臭氧消耗有影响。使用太阳能来驱动冷却循环是有吸引力的，因为冷却负荷大致与太阳能的可用性同相。为了利用太阳能冷却，一种解决方案是使用吸收式冷却器，使用水和溴化锂溶液。太阳能空调系统有助于减少化石燃料的使用。在不断发展的节能空调技术中，液体除湿空调( LDAC )系统在过去几十年中表现出了良好的性能，被认为是与广泛使用的传统空调系统(CAC)的强大竞争对手。干燥剂蒸发冷却技术环保，可用于调节建筑物室内环境。与传统空调系统不同，除湿空调系统可以由太阳能和工业废热等低级热源驱动。在这项研究中，重点是通过使用太阳能来降低空调能力、节省燃料和减少排放。

关键词：太阳能，除湿空调系统，加湿，除湿，常规空调 一.介绍 太阳能作为一种可再生能源，越来越受到世界各国的重视。太阳系可分为两类:这些是将太阳能转换成热能的热系统和将太阳能转换成电能的光伏系统。然而，更多落在光伏电池上的太阳辐射不是转换成电能，而是反射或转换成热能。由于光伏电池工作温度的升高，这种方法导致电转换效率下降。

在过去的一个世纪里，科学界在两个主要方面付出了很大努力来实现住房的能源可持续性；
这些国家正在减少外部能源供应，其余国家则使用可再生能源。在这两方面，太阳能都越来越受欢迎，因为它们增加了能源的独立性和可持续性，同时对环境几乎没有影响。

现代舒适的生活条件是以巨大的能源为代价的。全球变暖和臭氧消耗，以及过去几年化石燃料对建筑能源系统设计和控制的成本上升。太阳能资源丰富、清洁，用太阳能替代传统能源具有重要意义。因此太阳能在建筑能源系统中起着重要作用。

化石燃料越来越稀缺，成本越来越高，减少温室气体排放的激励措施也使得人们对太阳能越来越感兴趣。太阳能价格低廉，能够满足家庭全年的需求。不幸的是，它的间歇性和随天气条件、时间和季节的变化导致供暖需求和太阳能供应之间的不匹配。

空调系统安装在建筑物中，为居住者提供健康和生产环境。在广泛使用的能源效率低的传统空调系统的运行中消耗了大量的能量，这导致了一些与能源生产相关的环境问题，例如空气污染、全球变暖和酸雨。

从最近的研究来看，这些建筑消耗了全球约40 %的一次能源，排放了近33 %的温室气体。

空调系统由依次布置的部件和设备组成，以便加热或冷却、加湿或除湿、清洁和净化、减少令人反感的设备噪音、运输经调节的室外空气并将空气再循环至经调节的空间，并控制和维护室内或在最佳能源使用的封闭环境。

大多数空调系统执行以下功能: a .提供所需的冷却和加热能量 b .调节供气、加热或冷却、加湿或除湿、清洁和净化以及减弱这些系统产生的任何不良噪声 c .将包含足够室外空气的调节空气分配到调节空间 d .控制并保持室内环境参数，如温度、湿度、清洁度、空气运动、声级和调节空间与周围环境之间的压差在预定范围内。

1.1 .空调系统的应用 a.学校、学院、大学、图书馆、医院、疗养院、博物馆、室内运动场、电影院等机构建筑……等等。

b.商业建筑，如办公室、商店和购物中心、超市、百货公司、餐馆等。

c.居住建筑，包括酒店、汽车旅馆、单身家庭和三层或三层以下的多户低层建筑。

d.制造建筑物，制造和储存药品等产品。

e.汽车、飞机、铁路车辆、公共汽车、邮轮等交通运输行业....等等。

空调系统主要是为了乘客的健康和舒适。它们通常被称为舒适空调系统。

1.2 .空调系统原理 图1显示了安装在窗户上的空调系统。机柜分为室内和室外两部分，室内和室外由隔热墙隔开，以减少热传递。DX盘管与室内风扇位于室内和室内。室外舱包括压缩机、冷凝器、室外风扇、毛细管和风扇电机。风扇电机通常具有双端轴，一次驱动两个风扇。

图1.窗式空调 来自调节空间的返回空气流过粗空气过滤器，在DX盘管中冷却和除湿，然后进入室内风扇的入口。在室内空调中，室内风扇是前向弯曲离心风扇。经调节的空气在叶轮中被加压，并被迫通过通向供应格栅的空气通道。然后将调节后的空气供应到调节后的空间以抵消空间冷却负荷。

室外空气由螺旋桨风扇抽出并通过冷凝盘管，在冷凝盘管中热气态制冷剂冷凝成液态制冷剂。冷凝时，冷凝热通过冷却空气释放到外部。室外通风空气的一部分被室内风扇抽出并与回风混合。室外通风进风口开度可调。

科学家和工程师正在努力开发更有效的空调系统，能够以低能耗率和空气污染排放实现良好的室内空气质量。在不断发展的节能空调技术中，液体除湿空调( LDAC )系统在过去几十年中表现出了良好的性能，被认为是与广泛使用的传统空调系统( CAC )的强大竞争对手。

由于夏季除湿过程，空调系统的空气处理很潮湿，细菌很容易繁殖和发育。此外，潮湿的中央空调系统的空气湿度很少受到控制。这使得人们在这样的空调房间里感到不舒服。太阳能驱动液体除湿冷却空调系统( LDCS )能够改善室内空气质量，降低电能消耗，近年来受到研究人员和工程师的高度重视。

基于干燥剂的空调系统逐渐成为传统蒸汽压缩空调系统的潜在替代方案之一。

1.3 .文献综述 Ahmed H.Abdel Salam和Carey J.Simonson ( 2014 )提出了一种使用TRNSYS建筑能量模拟软件建模的膜式液体除湿空调(M-LDAC)系统。从技术、环境和经济角度对本研究调查的四种空调系统进行了评价。他们发现，带有ERV的系统的能耗随着排气气流的减少而增加。当废气从1降至0.6时，CAC-ERV的能耗增加了11%，M-LDAC-ERV增加了6%。当使用M-LDAC系统时，CO2排放量比CAC系统减少了19%，当废气使用的ERV等于M-LDAC系统中的单位时，CO2减少了31%。发现M-LDAC系统的电、热和总COPs分别为3.45、1.95和0.68。从技术环境和经济角度来看，M-LDAC系统是一个很有前途的系统。通过将能量回收通风器、太阳能热系统或热泵与所提出的M-LDAC系统集成，可以实现更多的节能。

BalghouthiM等人(2008年)利用TRNSYS和EES程序利用气象数据进行了计算机建模和仿真。针对150m2典型建筑优化的系统包括容量为11kw的溴化锂吸收式冷水机组、从水平方向倾斜35°的30m2平板集热器区和800±1个热水储罐。仿真结果表明，吸收式太阳能空调系统在突尼斯条件下是适用的。

ElsherbiniA.L.和MaheshwariG.P.(2010)他们发现，由于遮光导致的性能系数(COP)的理论增加在2.5%以内，理想效率的这种小的提高在更高的环境温度下降低，当需要提高效率时。遮阳带来的实际效率提升预计不会超过1%，日常节能将会降低。

郭杰、沈海庚( 2009 )结合动力学模型研究了集总法，研究了R134a太阳能喷射式制冷系统( SERS )的性能和太阳能含量。他们发现，在办公时间，即上午9 : 00至下午5 : 00，当运行条件为:发电机温度为85℃，蒸发器温度为8℃，冷凝器温度随环境温度变化时，系统的平均COP和平均太阳辐射分数分别为0.48和0.82。与传统的基于压缩机的空调相比，该系统可节省高达80 %的电能。

Ha Q P和vakloaya V ( 2014 )研究了一种新型混合太阳能辅助空调系统的性能增强和能效提高。单级蒸汽压缩太阳能空调由六大部件组成，压缩机、冷凝器、膨胀装置、蒸发器、太阳能真空收集器和太阳能储罐。在这种新的配置中，在压缩机之后的排放管线中实施旁通管线，以经由双向阀控制制冷剂质量流量，同时变速驱动器连接到空冷冷凝器以调节冷凝器风扇空气流量。通过模拟发现，无论采用新结构还是不采用新结构，进入膨胀阀的制冷剂焓都降低了8.5 %。在稳态条件下设计，无控制系统和开发的系统压缩机功耗分别为1.45 kw和1.24 kw，节能14 %。使用该系统的平均功耗比未控制系统低9.7 %。压缩机和冷凝器风扇的平均节能潜力为7.1 %和2.6 %。压缩机和冷凝器的降低最终会导致COP的增加。所开发系统的平均供电温度由13.77℃降至11.44℃，新开发系统和原系统夏季用电的平均能耗均低于未控制电厂的用电。对于控制中的闭环系统，与未控制的系统相比，在多变量控制下使用所提出的系统可以节省压缩机消耗的7 %至14 %的电力。他们得出结论，这种新设计有望在满足冷却需求的同时提高系统性能，并实现高能效。

Ibrahim I El Sharkawy等人 (2014) 从理论上考察了在中东地区气候条件下工作的太阳能吸附硅胶/水基冷却系统的性能。采用双床硅胶/水式吸附冷水机组。他们发现, 在开罗和吉达气候条件下工作的系统的最大循环平均冷却能力在阿斯旺气候条件下达到14.8 千瓦和15.8千瓦。无热水缓冲存储系统的冷却能力在中午达到最大值, 对于具有热水缓冲存储的系统, 最大冷却容量为13千瓦, 达到14:00 和15:00 小时的时间范围。具有热水缓冲储存系统的冷却能源生产市场波动较小。与没有热水缓冲储存的系统相比。

Lucas M等人（2003）在西班牙的实验室屋顶上安装了Hydrosolar屋顶样机。这座大楼装有冷凝器，冷凝器与太阳能屋顶一起作为冷凝器工作。该原型的四个单元占据的总体积约为6米*6米*1.2米的大小。在2000夏季,系统被监测,以获得实际安装和在实际条件下的性能数据。建立了CFD模型并进行了分析。通过实验结果和数值计算结果证实,由于自然和强迫对流,空气质量流通过通道引起。自然对流是由太阳辐射加热产生的银和强迫对流是由于风吸力效应在通道的输出。因此,影响系统性能的两个主要气象因素是太阳辐射和风速。

Ma Q 等人(2006) 研究了混合空调系统的性能, 并观察到, 混合空调系统的性能比传统的蒸汽压缩制冷系统高出 44.5%, 潜在负荷为 30%, 改善可以达到73.8% 在一个潜在的42% 负载。

Min Tu等人 (2010) 对低品位热能驱动的液体除湿空调系统的两种新型结构进行了比较。

Moncef Balghouthi等（2005）研究了突尼斯条件下太阳能吸收式冷却技术的TRNSYS程序模拟研究。为了优化影响系统性能的各种因素，进行了许多模拟。他们的仿真结果表明，吸收太阳能空调条件的太阳能空调系统适合突尼斯的条件。

Sukamongkol Y等人（2010年）进行了一项实验测试，以研究开发的模拟模型在预测混合PV/T空气加热收集器的冷凝器热回收动态性能方面的有效性。系统产生的热能可产生高达53°C和23％相对湿度的温暖干燥空气。每日电量的6％可以从系统中的PV / T收集器获得。使用混合式PV/T空气加热器，并结合从冷凝器回收的热量再生干燥剂进行除湿，并将空调系统的能耗降低18％。他们的结论是，实验验证结果表明，所开发的仿真模型能够在可接受的精度范围内预测冷凝器热回收的性能，其中使用混合PV/T空气加热器来再生干燥剂以减少空调室的能量使用。

Thosapon Katejanekam和Kumar S（2008）的仿真程序用于以日常概况的形式预测系统的运行和性能参数。他们发现，系统的平均空气相对湿度降低了15％。来自太阳能C/R的再生空气比进入的环境空气更暖和干燥。他们研究了系统性能，结果发现通风空气流量有所变化，他们发现40,60和80立方英尺通风率的效率比基础20 CFM降低了23％，45％和68％。因为空气和除湿机内的干燥剂之间的接触时间较短。通风量为20,40,60和80CFM时，空气相对湿度日均值分别为43.12％，48.49％，52.83％和57.15％。这是由于更高通风率下的水分去除效果较差。在40,60和80CFM的通风速率下，水分去除率增加了48％，58％和26％，而蒸发率增加了17％，20％和6％。

Tingyao Chen等（2007）设计了一个独立于设计干球和湿球温度的太阳能空调系统。与新设计的干式灯泡和湿球温度相比，此设计重合的干球和湿球温度高出6°C以上。通过这种新方法，当发生峰值冷负荷时，HVAC工程师可以避免在一年中的每个月的一个设计日计算24小时冷负荷。这种新方法和设计的天气数据可以直接确定房间或建筑物的峰值冷负荷，但热滞后小于1小时。

Tingyao Chen( 2010 )对液体除湿空调系统中的内热式和绝热式蓄热器进行了研究。采用传热传质模型对内热式和绝热式蓄热器的性能进行了分析和比较。他们发现，与传统的填充式再生器相比，内加热式再生器可以获得更好的再生性能。内热式再生器不仅可以提高再生率，而且可以发挥更高的能量利用效率。内热式再生器可以在低干燥剂流速下提供相当的再生效率和再生速率，因此应该是避免干燥剂液滴携带的好选择。较高的空气流速将导致再生热效率的降低，尽管实现了较高的再生速率。

Yong Gao Yin等人( 2007 )对入口空气温度从29℃变化到34.1℃时，空气除湿率从0.104g/sec降至0.073g/sec进行了实验研究，发现填料再生器的平均传质系数为4g/m2sec。当干燥剂溶液质量浓度为20%、加热温度为77.5°C时，最大传质系数为7.5g/m2sec。在本实验中，进气湿度为11.5g/kg~35g/kg，温度为28.5°C，干燥剂溶液温度为55~70°C，溶液出口温度为39.5~43°C，空气出口温度为32~35°C，发现除湿率随进气湿度的增加而明显增加。

空调系统的性能系数(COP)在0.7到1.2之间变化。

二.结论 从文献综述可以看出，在这个美丽的地球上，能量和水是我们所有人正常生活的基本必需品。太阳能技术及其应用对发展中国家和欠发达国家维持能源需求非常重要和有用。

太阳能冷却系统的主要动力是用可再生热源，即太阳能收集器的低品位热量，取代电力作为空调系统的优质能源。

太阳冷却是应对气候变化的一个好例子。应使用长期数据证明空调系统的可行性。

致谢 首先，我要感谢JNT大学的A.V. Sita Rama Raju教授，他提出了阅读太阳能蒸馏领域众多研究出版物和撰写评论论文的宝贵建议。我感谢JNT大学K.Vijaya Kumar Reddy 和 Professor B. Sudheer Prem Kumar教授以及我的父母，感谢他们鼓励我撰写这篇研究论文。

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