基于Cromer循环转轮除湿复合空调系统的性能分析

Cromer循环转轮除湿复合空调系统将转轮除湿与表冷器冷却除湿有机地结合起来,转轮除湿实现系统内部的水分转移,表冷器的冷却除湿把全部湿负荷排到外部环境。本文介绍了Cromer循环转轮除湿复合空调系统的工作原理及特点,给出了其与直接冷却除湿处理新风的比较实例。结果表明,在相同供冷水温度下,该复合空调系统能比直接冷却除湿系统实现更低的送风露点温度,提高表冷器的除湿能力;考虑低温新风可以承担室内显热冷负荷,二种新风处理方法对总的节能性没有影响,但前者送风温度接近13℃且低湿,送风品质更高。该方法可以改善室内空气品质,与直接冷却除湿方法相比不增加制冷能耗,且切实可行,值得进一步研究推广。     

氯化锂除湿在空调节能改造工程中的应用

溶液除湿空调系统由于其显著的节能优势及其对室内空气品质的良好影响,近年来得到了较快发展。目前常用而且吸湿性能比较优异的除湿剂有LiCl和LiBr。文章通过对铜箔车间空调改造为例介绍氯化锂除湿机组在电子厂房上的应用,并结合改造厂房的实际情况详细介绍厂房的节能改造工程。     

适用于近零能耗建筑的一种自然换热空调末端的除湿能力研究

针对近零能耗建筑的低冷热负荷与室内高热舒适度的特点,笔者提出一种自然换热空调末端设备,能够实现冬季供暖和夏季供冷与除湿,并且没有强制对流换热,也无噪音,非常有利于形成室内舒适的空气环境;该空调末端的除湿性能是其与辐射末端(同样可以冷热兼供)相比的突出优势,因此,本文对该自然换热空调末端除湿能力的量化计算展开研究。经理论分析与推导,并结合空调末端的实际应用条件,最终得到适用于该空调末端凝结水量计算的半经验数学模型,同时利用实测数据对该模型进行了验证。为便于工程应用,进一步给出了常见空调室内空气参数条件下,单位设备表面积凝结水量计算的诺莫图。     

昆明地区冬季空调不加湿对室内空气参数的影响

基于质量守恒方程,导出了冬季空调不加湿时室内空气含湿量的计算公式,综合考虑影响含湿量的主要因素,得出冬季空调不加湿时应满足的条件,并考察了昆明地区具有代表性空调房间冬季空调不加湿时室内相对湿度是否满足设计要求。结果表明:在昆明地区冬季空调不加湿时,商场的相对湿度高于设计要求,需要除湿;酒店多功能厅及餐厅空调系统不加湿亦可达到设计要求;而影剧院、酒店客房的相对湿度低于设计要求,空调系统必须加湿。     

某除湿车间空调系统改造分析

针对某除湿车间湿度无法达到设计值(≤70%)的情况,先对除湿系统室内、外设计参数进行探讨,阐述夏季空调室外设计参数不能作为除湿空调系统室外设计状态点。其次通过计算,表明维持室内的正压是保证室内相对湿度的关键因素,如果不维持正压,将带来大量的室外渗透湿负荷,给出维持室内正压所需最小新风量的计算。再次介绍除湿空调系统再热量的计算问题。     

空调表冷器降温除湿能力图

针对传统空调设计方法中空气状态参数仅依赖焓湿图而与空气调节设备能力脱节的问题,给出了针对不同空调表冷器的降温除湿能力图。该图不仅可以反映常规焓湿图所反映的室内空气干球温度、含湿量、相对湿度、比焓等状态参数,还可以反映某一型号空调表冷器的显热负荷和潜热负荷处理能力,从而可以方便地显示空调末端的整个空气调节过程,并可以确定某一型号空调表冷器在不同室内空气热湿负荷下处理室内空气的稳定工况点。     

关于夏季热湿负荷的分别解决方式

夏季的空调负荷可分为2个部分，1．用于降低室内温度：2．是用于去除室内空气中的水分。 降低室内温度仅需略低于室温（26℃）即可。而除湿就需要低于露点温度，且越低除湿能力就越大。根据制冷原理，温度越低其COP就越小。因此，现有的空调系统为了满足除湿要求将冷冻水的温度定为7℃。即降温和除湿均用7℃的水，这就造成了能源的浪费。     

确定长江流域供暖空调能耗指标的边界条件

讨论了影响长江流域住宅供暖空调能耗水平的诸因素，包括热环境质量、室内空气品质和新风量、供暖空调系统和比和性能系数、供暖期空调期除湿期天数及建筑热工特性等，给出了这些因素的建议值。     

一种新型转轮除湿与双级热泵耦合空调系统及系统设计

本文提出了一种新型转轮除湿与双级热泵耦合的空调系统,首先采用热湿负荷独立处理的思想,利用双级热泵来满足室内冷负荷和转轮再生负荷的要求,而后建立了系统的物理模型并对该系统的性能参数进行了计箅和分析,在满足室内热湿负荷和转轮再生负荷的要求下,双级热泵的2台机组均可同时工作在较高效率范围内.从节能、环保和室内空气品质的角度分析,该系统具有很大的发展潜能.     

采用冷冻除湿的温湿分控户式空调系统的送风分析

采用冷冻除湿的温湿分控户式空调系统,可将室内显热负荷与湿负荷分开处理,采用辐射方式处理显热负荷,送风承担湿负荷,同时也承担一部分室内显热负荷。因此,如何选定合理的送风温度和送风量是需要解决的问题。本文首先以送风承担室内显热负荷最小为目标,计算最佳的送风量及送风温度;然后,研究在不同的室内湿负荷条件下,送风量对送风承担室内负荷以及空调系统能耗的影响,考虑室内人员对新风的要求后,得到合理的送风温度;最后,计算了采用冷冻除湿的温湿分控空调系统的能耗,与常规温度控制空调系统的能耗进行比较,得到了在合理的送风温度下,如果采用新风处理室内湿负荷,温湿分控空调系统比常规温度控制空调系统节能11%~46%,如果采用回风处理室内湿负荷,则温湿分控空调比常规温度控制空调系统节能21%~46%。     

A comparative study of different control strategies for indoor air humidity

There has been a rising concern in controlling the high indoor humidity of hot and humid countries. When an air-conditioned space experiences only part of its design heat load, its humidity tends to rise as a result of the air-conditioning system trying to control the indoor temperature by reducing its cooling capacity. In this study, the part-load dehumidification performances of three temperature control strategies are compared, namely, chilled water flow control, bypass air control and the variable air volume control. Coil simulations are employed to study the part-load performance of these control strategies. The coil model has been validated with experimental data to within ±6.5%. The relative humidity of a space depends of factors such as design sensible heat factor of the space, temperature control strategy employed and load condition experienced by the space. Simulation results have indicated that chilled water control strategy results in the highest indoor humidity throughout the range of conditions studied while variable air volume system provides highly effective dehumidification performance of the cooling coil. Bypass air control appears to be a good option for adoption as it is able to provide an acceptable humidity over a wide range of load conditions without having to affect the air movement within the space.     

Experimental study on dehumidifier and regenerator of liquid desiccant cooling air conditioning system

A new type of air conditioning system, the liquid desiccant evaporation cooling air conditioning system (LDCS) is introduced in this paper. Desiccant evaporation cooling technology is environmental friendly and can be used to condition the indoor environment of buildings. Unlike conventional air conditioning systems, the system can be driven by low-grade heat sources such as solar energy and industrial waste heat with temperatures between 60 and 80 °C. In this paper, a LDCS, as well as a packed tower for the regenerator and dehumidifier is described. The effects of heating source temperature, air temperature and humidity, desiccant solution temperature and desiccant solution concentration on the rates of dehumidification and regeneration are discussed. Based on the experimental results, mass transfer coefficients of the regeneration process were experimentally obtained. The results showed that the mean mass transfer coefficient of the packing regenerator was 4 g/(m² s). In the experiments of dehumidification, it was found that there was maximal tower efficiency with the suitable inlet humidity of the indoor air. The effective curves of heating temperature on the outlet parameters of the regenerator were obtained. The relationships of regeneration mass transfer coefficient as a function of heating temperature and desiccant concentration are introduced.     

夏热冬冷地区住宅建筑新风系统全年运行工况分析

根据夏热冬冷地区的空调期、除湿期和采暖期的划分方法,提出了住宅建筑新风系统全年运行的转换条件,以及新风热湿处理工况要求。并针对该地区气候潮湿、除湿期时间长的特点,认为节能住宅采用温湿度同时监控的独立新风系统,有利于改善室内热环境质量和室内空气质量。     

中国国家博物馆暖通空调系统设计

介绍了国家博物馆兼顾文物保护、参观者舒适感和运行调节手段确定室内环境参数的原则。分析了采用部分负荷冰蓄冷、大温差低温冷水系统在负荷保证、提高除湿能力和节能方面的优势。结合CFD模拟,采用了分层空调加地板辐射供冷的空调系统以改善高大空间的室内环境。探讨了博物馆中文物库房和展厅恒温恒湿空调系统的设计方法。     

夏热冬冷地区民用建筑除湿方式的适用性分析

本文对常见的几种空气除湿的原理进行了分析,针对夏热冬冷地区的建筑气候特点,比较了冷冻除湿、通风升温除湿、被动除湿、干式除湿和复合式除湿等各自的特点和适用场合。分析了该地区空气处理设备实现温湿度独立控制的必要性,强调了空调设备设计选型时不能只考虑设备显热冷负荷,说明了湿度控制对空气处理设备设计选型的要求,提出了独立新风系统集中除湿和室内空气湿度独立控制的重要途径,并从室内环境质量综合控制角度指出了民用建筑空气除湿技术和该地区空气湿度控制方式的发展趋势。     

Experimental study on a residential temperature-humidity separate control air-conditioner

According to the temperature and moisture characteristics and current problems experienced in the Yangtze River Area, a temperature-humidity separate control air conditioner was developed. This unit can remove indoor sensible heat and latent heat load separately, and adjust indoor temperature and humidity respectively, thus improve indoor comfort and reduce energy consumption. The air-conditioner consists of an air cooling evaporator and a water cooling evaporator. Orthogonal experiments were designed to study the influence of outdoor temperature, indoor temperature, indoor humidity, compressor frequency, and refrigerant distribution ratio in air cooling evaporator (RDRAE) on the unit performance. The results showed that the dehumidification capacity ranged from 0 to 4.02 kg/h; the EER ranged from 2.71 to 4.57; the cooling capacity ranged from 6822 to 13,080 W. The results can help to make the control logic of the unit, and be used as the basis of energy consumption calculation. Units with temperature and humidity separate control could save about 15.6% of the cooling energy consumption against traditional residential air-conditioner, and 47.8% against the traditional residential air-conditioner that could control both indoor temperature and humidity.     

Analysis on the ideal energy efficiency of dehumidification process from buildings

As dehumidification is one of the most important tasks of environment control of the building, it is necessary to know the energy efficiency of dehumidification processes. The energy efficiency can give the energy cost of drawing moisture from indoor air to the outside environment. This paper presents analysis of the ideal cost of dehumidification process by a liquid desiccant cycle. Formulas to calculate ideal efficiency of dehumidification process are obtained, which is determined by indoor temperature, outdoor temperature, and the temperature of the intersection point of the iso-relative humidity line of indoor air and the iso-humidity ratio line of outdoor air. The ideal efficiency of the condensing dehumidification method is lower than the ideal dehumidification process, due to the fact that condensing dehumidification method must dehumidify the air at the temperature of dew point. Results from this paper can be used as theoretical foundation for the further analysis of various dehumidification methods and the development of new dehumidification processes.     

A model to study the effects of different control strategies on space humidity during part-load conditions

Many air conditioning systems have small moisture removal capacities and are not equipped to maintain space humidity under part-load conditions particularly during hot and humid periods. They are able to provide desired temperature control but humidity. The primary objective of this work is to identify control strategies that can be used to prevent significant indoor humidity degradation during part-load conditions. These control strategies are chilled water flow control, bypass air control, variable air volume control, run-around coil control and low face velocity/high coolant velocity control. Coil simulations have been employed to study the part-load performance of these control strategies. The coil model compares favourably with experimental data to within ±6.5%. Simulation examples are conducted for each control strategy under varying part-load conditions. Results from the coil model have indicated that some strategies are more effective than others in sustaining acceptable indoor humidity under part-load conditions. For instance, chilled water control strategy has been observed to produce highest indoor humidity throughout the range of conditions studied while variable air volume system provides highly effective dehumidification performance of the cooling coil. In addition, higher ventilation rates have been observed to increase the space humidity during part-load conditions.     

室内恒温泳池综合节能方案研究

基于广州某会所室内恒温泳池的温湿度设计参数,计算了该泳池全年制冷、除湿、泳池加热和采暖负荷动态需求。通过分析动态冷热负荷曲线提出冷凝热回收应作为泳池综合节能方案的基本出发点,进一步比较了泳池专用热泵系统与全热回收风冷热泵系统两种方案的运行特点和全年能耗特性,并建议采用小型热回收型热泵系统与普通风冷热泵的组合方案。     

利用冷凝热再生的复合除湿空调除湿潜力分析

简要描述了利用冷凝热再生的复合除湿空调系统形式及其节能性特点;在热力学第一定律和热力学第二定律的基础上,分别以冷凝器和除湿转轮为控制体,建立了复合除湿空调的系统热力学模型,并给出模型求解框图,从而可以求得复合除湿空调系统的除湿量;最后,计算了在不同转轮效率和室内单位面积显热负荷下的系统单位面积除湿量,并讨论了新风量大小对结果的影响;结果表明,在现有转轮效率和常见单位面积负荷指标下,转轮的除湿量小于新风湿负荷（1次/h）,而降低新风量后（0.5次/h）,当转轮效率较高和室内显热负荷较大时,转轮能够承担新风湿负荷。