节能型除湿制冷空调系统的性能研究

本文分析了几种除湿制冷空调系统工作原理，提出了除湿制冷空调系统的性能计算公式。通过计算，分析了多种工况对系统性能的影响，得出除湿制冷空调系统的ＣＯＰ可达４左右。相对于常规制冷空调系统而言，除湿制冷空调系统不仅低噪音，同时亦是一种节能型空调系统。     

太阳能液体除湿空调系统再生和蓄能特性的研究

太阳能液体除湿空调系统中,能量在液体除湿剂中以化学能的形式存在,蓄能潜力大,再生温度低,可以利用太阳能或其它低位余热和废热。着重分析了液体除湿空调系统中溶液的再生原理和再生过程的传热传质特性,对再生过程进行了实验研究,获得了再生过程对流传质和对流换热的实验准则方程,讨论了各主要因素对再生量的影响。对再生器的蓄能特性进行了分析,讨论了太阳能液体除湿空调系统蓄能工况的运行方式。     

太阳能液体除湿空调性能的实验研究

在对液体除湿机理研究的基础上，建立了太阳能液体除湿空调系统实验台，采用氯化钙溶液作为除湿剂，对系统的除湿性能进行了实验研究，对影响除湿的各主要因素进行了分析。     

液体除湿系统的实验研究

介绍了液体除湿实验系统,采用氯化钙溶液作除湿剂,除湿设备为装有不锈钢波纹孔板规整填料的填料塔。实验研究了除湿剂的流量,浓度等参数对空气出口湿度的影响。     

液体除湿特性的实验研究

从保护环境、节约能源出发,对太阳能液体除湿空调系统的优点进行了讨论,建立了液体除湿实验台,提出一种新的氯化钙和氯化锌组成的混合工质（摩尔比为1：1）作为除湿系统的除湿剂、并对影响液体除湿特性的各因素分析,最后指出液体除湿空调系统是一种很有潜力的空调方式。     

液体除湿空调系统的数学模型与性能分析

建立了一种液体除湿空调系统，核心部件为液体吸收式除湿器，蒸发冷却器是重要组成部分，两者的主体均采用蜂窝结构。给出了统一的数学模型，对除湿器和冷却器内复杂的传热传质过程进行描述。数值模拟结果与实验数据基本一致。运用上述模型编制程序，对系统性能进行预测，表明液体除湿空调系统方案可行。     

太阳能液体除湿空调系统中除湿器型式的选择

太阳能液体除湿空调系统是一种利用太阳能等低温热源的节能空调系统。除湿器直接影响太阳能液体除湿空调系统的性能。本文从焓湿图、蓄能、MR的选取和除湿效果等几个方面对目前被广泛应用的两种典型的除湿器进行了比较分析。     

液体除湿空调实验台的性能分析及实验研究

针对上海气候环境条件设计制造了利用80℃以下低品位热源驱动的全新风送风LiCl液体除湿空调实验台,用于为100m2空调区域提供19℃以下的送风,独立承担室内热湿负荷.分析测试了系统送风温度的影响因素,表明再生热源温度是主要影响因素.该系统结构适合采用除湿再生同时运行模式,该模式下系统运行性能为:夏季工况新风制冷量为35～49kW,热力COP为0.72～0.98;秋季工况为17～29kW,热力COP为0.30～0.51.最后验证了除湿再生独立运行模式的可行性与实际效果:新风制冷量45kW,热力COP为1.1,为今后实验台的改进指明了方向.     

开式除湿冷却型空调系统理想性能分析

利用热力学第二定律对热能驱动的任意结构型式的开式除湿冷却型空调系统进行了理论分析，得到了此类空调系统在可逆条件下的理想性能，并以一种改进型的开式除湿冷却型空调系统为例，模型分析了等效冷凝器的出口气流状况，等效蒸发器的出口气流状况等条件对系统理想性能系数的影响，为改进开式除湿冷却型空调系统的性能提供了有益的思路。     

Experimental investigation of a liquid desiccant system for solar cooling and dehumidification

Growing demand for air conditioning in recent years has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the environmentally-friendly techniques which may help alleviate the problem. A promising solar cooling method is through the use of a liquid desiccant system, where humidity is absorbed directly from the process air by direct contact with the desiccant. The desiccant is then regenerated, again in direct contact with an external air stream, by solar heat at relatively low temperatures. The liquid desiccant system has many potential advantages over other solar air conditioning systems and can provide a promising alternative to absorption or to solid desiccant systems.Earlier work by the authors included theoretical simulations and preliminary experiments on the key components of the liquid desiccant system. The objective of the present study has been to construct a prototype system based on the knowledge gained, to monitor its performance, identify problems and carry out preliminary design optimization. A 16 kWt system was installed at the Energy Engineering Center at the Technion, in the Mediterranean city of Haifa. The system comprises a dehumidifier and a regenerator with their associated components operating together to dehumidify the fresh (ambient) air supply to a group of offices on the top floor of the building. LiCl-water is employed as the working fluid. The system is coupled to a solar collector field and employs two methods of storage – hot water and desiccant solution in the regenerated state. The performance of the system was monitored for five summer months under varying operating conditions. The paper describes the operation of the experimental system and presents the measured data and the calculated performance parameters.     

A simulation model for the performance of a hybrid liquid desiccant system during cooling and dehumidification

A finite difference model describing simultaneous heat and mass transfer in a hybrid liquid desiccant cooling system is presented in this paper. This type of system provides cooled and dehumidified air by a combination of a packed absorber tower and a conventional vapour compression system. The model will allow the prediction of the rate of condensation in the dehumidification tower and the evaporator of the vapour compression system, the conditions of the air and liquid desiccant leaving the tower, the conditions of the air leaving the evaporator, and other important parameters. The mathematical model results were validated with existing experimental data for a similar system with an uncertainty of 10.5% for the total rate of condensation and 0.8°C for the evaporator air exit temperature. Copyright © 2005 John Wiley & Sons, Ltd.     

Turbine inlet cooling with thermal energy storage

Turbine inlet cooling (TIC) is a common technology used to increase combustion turbine power output and efficiency. The use of mechanical or absorption chillers for TIC allows for more air cooling than evaporative methods and also imposes a significant parasitic load to the turbine. Thermal energy storage (TES) can be used to shift this load to off‐peak hours. Use of thermal storage increases the flexibility of turbine power output, which benefits from the application of optimization tools. This paper explores the effect of combining TIC with TES to enhance the performance of a district cooling system that includes a gas turbine for power generation. The work illustrates how the system's performance can be enhanced using optimization. Application of multi‐period optimization to the system that includes TES brings significant operational cost savings when compared with a system without thermal storage. It is also shown how TES provides demand‐side energy management in the district cooling loop and supply‐side management through the use of TIC. In addition to the optimization study, a thorough literature review is included that describes the current body of work on combining TIC with TES. Copyright © 2013 John Wiley & Sons, Ltd.     

Experimental investigation and performance analysis on a solar adsorption cooling system with/without heat storage

A solar adsorption cooling system which can be switched between a system with heat storage and a system without heat storage was designed. In the system with heat storage, a heat storage water tank was employed as the link between the solar collector circulation and the hot water circulation for the adsorption chillers. However, the heat storage water tank was isolated in the system without heat storage, and the hot water was directly circulated between the solar collector arrays and the adsorption chillers. It was found that the inlet and outlet temperatures for the solar collector arrays and the adsorption chillers in the system without heat storage were more fluctuant than those of the system with heat storage. Also found was that the system with heat storage operated stably because of the regulating effect by the heat storage water tank. However, under otherwise similar conditions, the cooling effect of the system without heat storage was similar to that of the system with heat storage. Compared with the system with heat storage, the system without heat storage has the advantages of higher solar collecting efficiency as well as higher electrical COP.     

Experimental tests of a small‐scale microturbine with a liquid desiccant cooling system

In a trigeneration plant, the thermal energy recovered from the prime mover is exploited to produce a cooling effect. Although this possibility allows the working hours of the plant to be extended over the heating period, providing summer air conditioning through thermally activated technologies, it is rather difficult to find in the literature experimental data on trigeneration plants operation, and the availability of performance characteristics at off‐design conditions is anyway limited. The paper has the aim of showing the experimental data of a real trigeneration system installed at the Politecnico di Torino (Turin, Italy), composed of a natural gas 100 kW_el microturbine coupled to a liquid desiccant system. The data are presented for both cogeneration and trigeneration configurations, and for full and partial load operations. An energetic and economic performance assessment at rated power operation is presented, and compared with the partial load operation strategy. The primary energy savings are calculated through a widely accepted methodology, proposed by the European Union, and through another methodology, reported in literature, which seems to the Authors more suitable to describe the energetic performances of trigeneration plants. Copyright © 2012 John Wiley & Sons, Ltd.     

Investigation on regeneration and energy storage characteristics of a solar liquid desiccant air-conditioning system

Solar liquid desiccant air-conditioner is a new air-conditioning system in which liquid desiccant can be regenerated by solar energy and energy can be stored in the form of chemical energy in the liquid desiccant. In this paper regeneration and energy storage characteristics were studied theoretically and experimentally. Two criterion equations for heat and mass transfer in the regeneration process were obtained. The main factors that influence the regeneration process were analyzed. A principal solar liquid desiccant air-conditioning system under energy storage operating mode is proposed. Translated from Acta Energlae Solaris Sinica, 2006, 27(1): 49–54 [译自: 太阳能学报]     

吊顶辐射冷却塔供冷系统试验研究与性能分析

通过供冷试验及TRNSYS软件模拟研究了吊顶辐射冷却塔供冷系统的运行效果,分析了气象参数、部件结构等因素对系统供冷效果的影响,并与常规供冷系统全年的运行能耗进行对比。试验与理论分析结果表明,吊顶辐射冷却塔供冷系统的有效供冷量能够满足用户供冷需要,供冷房间温度稳定且分布均匀。冷却塔供冷效果与大气湿球温度、建筑内部负荷、热交换器结构等因素有关。辐射顶板末端与冷却塔供冷匹配性高,系统全年运行时数增加,应用于需全年供冷的建筑节能效果显著。     

Experimental investigation of thermal performance of a solar assisted heat pump system with an energy storage

An experimental solar assisted heat pump space heating system with a daily energy storage tank is designed and constructed, and its thermal performance is investigated. The heating system basically consists of flat plate solar collectors, a heat pump, a cylindrical storage tank, measuring units, and a heating room located in Gaziantep, Turkey (37.1°N). All measurements are automatically collected as a function of time by means of a measurement chain feeding to a data logger in combination with a PC. Hourly and daily variations of solar radiation, collector performance, coefficient of performance of the heat pump (COP_HP), and that of the overall system (COP_S) are calculated to evaluate the system performance. The effects of climatic conditions and certain operating parameters on the system performance parameters are investigated. COP_HP is about 2.5 for a lower storage temperature at the end of a cloudy day and it is about 3.5 for a higher storage temperature at the end of a sunny day, and it fluctuates between these values in other times. Also, COP_S turns out to be about 15–20% lower than COP_HP. Copyright © 2004 John Wiley & Sons, Ltd.