【作者】 朱丹丹；

【导师】 燕达；

【作者基本信息】 清华大学 ， 土木工程， 2013， 硕士

【摘要】 空调冷冻站及冷冻水系统是空调系统的重要组成部分，其设计水平和实际运行管理会直接影响空调系统的能耗。通过大量的文献调研和实地测试，发现在空调冷冻水系统的运行和设计中存在着许多问题，如实际运行中冷冻水系统的“大流量小温差”现象、冷冻水系统形式的选择等。由于空调冷冻站及冷冻水系统的复杂性，影响因素众多，在分析设计方案时，需要我们对全年工况进行计算分析，这就需要既能反映实际现象又计算功能完备的模拟软件。目前较常用的能耗模拟软件虽然具有空调冷冻站全年能耗模拟计算的功能，但无法反映冷冻水系统的实际运行特性，其关键问题是这些软件缺少反映用户侧水系统整体性能的模型。用户侧水系统的整体特性决定了冷冻站的运行性能，但目前关于用户侧整体特性的研究成果较少，因此，本论文的主要研究目标是通过实际运行数据与模拟结果的比较，建立合理的用户侧整体模型，从而实现冷冻站和用户侧的联合模拟计算，以辅助解决设计阶段的实际问题。首先，本文从单个盘管的实际运行数据与换热模型出发，分析单个盘管的动态控制特性，并确定影响换热性能的关键因素。其次，根据盘管水阀控制的不同特点，本文分别针对连续控制盘管和通断控制盘管的水系统整体特性，进行了实际数据与模拟计算结果的对比，归纳其关键性影响因素，最终分别建立了两者的用户侧整体模型。然后，结合用户侧水系统的整体模型和冷站计算模型，建立了冷冻站及冷冻水系统的联合模拟计算方法，并在程序中实现。最后，本文对两种空调末端形式的冷冻水系统进行了不同工况下的模拟计算，包括一级泵变频控制运行工况和过渡季提高冷机出水温度的节能效果。本文为冷冻站及冷冻水系统的设计提供了一种全工况的模拟计算方法，可以为实际设计问题提供帮助，如冷冻水系统形式的选择、供水温度设计、压差控制等，也可以通过对各种技术手段的全工况模拟，来比较分析技术手段的运行性能和能耗水平。本文的工作使得我们更加理解用户侧冷冻水系统的整体特性，并提供有效的整体模型用于冷冻站的模拟计算，为解决设计阶段的实际问题提供帮助。更多还原

【Abstract】 Refrigeration station and chilled water system are paly a key role inair-conditioning systems, and its design and operation effect the energy consumption ofair-conditioning systems directly. A large number of literature studies and fieldinvestigations indicated that many unsolved problems and disputes exist in design, suchas chilled water systems operating with “large chilled water flow and low temperaturedifference”, the selection of water system type and so on. As it is very complex indesigning refrigeration station and chilled water system due to many effecting factors,we have to analyze the operating performance of chilled water system all conditionswith simulation tools. Although building energy simulation tools in the world, such asDOE-2, EnergyPlus, DeST and so on, can simulate the all-year conditions ofrefrigeration station and chilled water system hour by hour, the simulation results cannotreflect the real operating performance, which implies that models of refrigeration stationand chilled water system ignore some key influencing factors. In fact, the operatingperformance of the customer side chilled water system has a large effect on theperformance of refrigeration station and simulation tools now available do not havereasonable models for this part. Based on the literature studies, few research findingsare achieved about the characteristics and modeling method about customer side chilledwater systems. Thus, the research purpose of this paper is to build the model ofcustomer side chilled water systems by comparing the real operating results andsimulation results, applied in the combined calculation of refrigeration stations.Firstly, the real operating data and the simulation result of heat exchanger model ofone cooling coil was compared to determine the key influencing factors of the heatexchanger model, which is the base of the paper. Secondly, two types of cooling coilwere analyzed respectively, as the control method of water valves determines thecharacteristics of customer side chilled water systems. The two types are cooling coilswith continuous control and on-off control. Compared with the real operating results byBuilding Monitoring System and simulation results of cooling coil systems, keyinfluencing factors on the characteristics of customer side chilled water systems weredetermined, and then the models of the customer side chilled water systems were built. The chilled water flow rate and return water temperature could be calculated accordingto the supply water temperature and the chilled water pressure difference by the models.Thirdly, the combined calculation method of refrigeration station and chilled watersystem were achieved. Finally, the all condition performance and energy consumptionof the refrigeration station and chilled water system with VAV system or Fan Coilsystem in customer side were simulated. Based on the simulation results, we couldevaluate different design scheme and also help us to size the capacity of equipment andoptimize operations.The efforts of this paper help us understand the characteristics of customer sidechilled water systems, and also support effective models applied to the combinedcalculation of the refrigeration station and chilled water system, which is verysignificant for design work.更多还原