【作者】 唐娟；

【导师】 刘金平；

【作者基本信息】 华南理工大学 ， 工程热物理， 2011， 硕士

【摘要】 中央空调系统作为办公楼、宾馆酒店等现代建筑的耗能大户,合理的节能设计对整个建筑物的节能起到重要作用。随着电价不断上涨,不少业主开始有了对空调系统进行节能改造的要求。空调系统应该具备良好的调节性能,以适应空调系统大部分时间在部分负荷下运行的特点。冷水系统的调节主要分量调节与质调节,水泵变频属于量调节,变水温属于质调节。由于变水温调节具有实现条件较为简单、节能改造需要的二次投入少、并且不影响水系统的水力特性等突出优点,使得近年来对其的研究和应用越来越多,成为空调节能的主要手段之一。冷水温度越高,节能效果越好,并且只要调节合理,保证供水状态能够满足负荷的要求,变水温调节是不会影响空调舒适性的。本文基于传递函数法,依据典型气象年数据,编写了全年空调冷负荷计算软件。并对办公、公共饮食、宾馆饭店、医疗这4种典型公共建筑的空调负荷进行了模拟计算,并分析了各类建筑的最不利负荷率与平均负荷率的关系。结果表明：不同功能建筑的最不利负荷率与平均负荷率的比值有所不同,最大值为1.325,最小值为1；单一建筑不同时间的最不利负荷率与平均负荷率的比值也有所不同,上午最大,在1.1-1.325之间变化,午后较小,小于1.1；每天的8：00-11：00,由于东向房间首先受到太阳辐射的影响,与其它各朝向房间负荷率差异较大,而在其它时段,各朝向房间负荷率差异不是非常明显；当各类建筑的平均负荷率降低,其最不利负荷率也随之降低,因此当负荷率降低时,变水温调节是适用的。通过对表冷器进行校核计算和优化求解可以得到最佳的供水温度。采用计算热交换效率ε1和接触系数ε2的计算方法,对表冷器进行了校核编程计算。在保证室内环境在舒适性空调要求范围内的前提下,结合变水温调节仅适用于最不利负荷率与平均负荷率一致变化的情况下这一特点,以办公建筑为例,分别以平均负荷率和最不利负荷率为输入负荷率进行计算。计算结果表明：以这两种不同负荷率计算出来的冷水进口水温、送风温度以及室内相对湿度均一致变化,计算结果差异很小,故变水温调节对此类建筑是适用的。更多还原

【Abstract】 As major energy consumer of central air-conditioning in modern architecture including offices, hotels and so on, reasonable energy-saving design application system plays an important role on energy conservation of the whole building.Many building owners began to in request of energy-saving renovation to air conditioning system with rising electricity prices.The air-conditioning system should have good regulation performance because air conditioners are under part load operation in most of the time. The regulation of Chilled water system concluded quantity adjustment and quality adjustment, frequency conversion of water supply pump belong to quantity adjustment and variable chilled water temperature belong to qualitative adjustment. Due to variable chilled water temperature adjustment have many prominent advantages such as it could be realized simply, needing less investment in the secondary energy-saving reform, and having on effect on the hydraulic characteristics of the water system and so on, the variable chilled water temperature adjustment got more and more research and application during recent years, and becoming one of the principal means of energy-saving in air-conditioning system.The energy-saving effect was more and more better with temperature rise, variable chilled water temperature adjustment would have no impact on the comfort of air-conditioning as long as regulating reasonably and making sure water supply can meet requirements of cooling load.In this paper,based on the transfer function method and typical annual meteorological data, the software of annual hourly air-conditioning cooling load calculation was compiled,then the air-conditioning load of four typical public buildings were simulated, including offices, hotels, public canteens and hospitals, and the relationships between the most unfavorable load rate and the averaged load rate were analyzed. The results indicated that the ratios of the most unfavorable load rate to the averaged load rate would be different for different buildings, the maximum and minimum ratios were 1.325 and 1 respectively. Furthermore,The ratios four one kind of building would change with time, The values were maximum in the morning and changed between 1.1 and 1.325, and less than 1.1 in the afternoon. Due to east rooms were influenced by solar radiation firstly during 8:00 to 11:00 every day, the load rate was quite different from any other orientations rooms, but in other period of time, the differences of load rate in all orientations rooms were not obvious.The most unfavorable load rate would reduce following the decreased trend of the averaged load rate, also the variable chilled water temperature adjustment technology was applicable when the load rate decreased.The best chiller water supply temperature was worked out through check calculation and optimization solution of surface air cooler. counting method based on heat efficiencyεl and contact coefficientε2 was used to the check calculation of surface air cooler.Taking office building for example, in the premise of comfort requirements in indoor environment was guaranteed, combined with the characteristic that variable chilled water temperature adjustment only applied to the situation when the most unfavorable load rate and average load rate changed consistent, the most unfavorable load rate and the averaged load rate were taken as optimization input load rate data respectively. The calculation results indicated that chilled inlet water temperature, supply air temperature and indoor relative humidity are all changed consistent, the differences of these parameters were all small when inputting these two different load rates, so the variable chilled water temperature adjustment technology was applicable to this typical public buildings.更多还原