【作者】 刘刚；

【导师】 曹阳；

【作者基本信息】 中国建筑科学研究院 ， 供热、供燃气、通风与空调工程， 2010， 硕士

【摘要】 空调能耗作为建筑能耗的大户,对节能减排的重要性不言而喻。水蒸发冷却技术具有独特的“高效”和“替代”作用,正是完成相应节能减排任务所需的节能技术之一。本文以国家“十一五”科技支撑计划课题《村镇直接蒸发冷却关键技术及低品位能源综合利用研究》(2006BAJ04B04-1)为依托,以水蒸发冷却虚拟循环结构的(?)分析及不同温度的喷淋水对水蒸发冷却效果的影响为研究对象,在借鉴前人研究成果的基础上对直接水蒸发冷却的原理和传热传质过程行了分析；对直接水蒸发冷却过程建立了数学计算模型,并进行了推导和化简；针对不同温度的喷淋水对ηDECtw的影响进行了理论分析和实验研究。本文的研究内容如下：第一章中对水蒸发冷却所基于的热力学和传热、传质学的基本理论进行了简要的介绍,对两种形式的水蒸发冷却的极限做了探讨,着重分析了两个极限的实质。在第二章中建立了直接水蒸发冷却的虚拟循环结构,对循环过程中各个阶段工质发生的变化依据(?)分析理论进行了研究,由工程热力学的(?)方法指出能量的传递方向和数量,并对设备和系统的能量转化过程的优化进行了分析。依据(?)分析理论建立两个准则,为设备或系统的改进指明方向,为后续章节的研究奠定理论基础。在第三章中,将目前常见的采用循环水的直接水蒸发冷却过程进行了拓展。在分析直接水蒸发冷却过程时,考虑了不同温度的喷淋水对水蒸发冷却效果的影响,建立了传热传质方程组,科学地描述了直接水蒸发冷却过程中的传热传质现象。基于改进设备性能准则从理论上对影响水蒸发冷却的因素进行了分析,利用等焓降温加湿的直接蒸发过程对传热传质方程组进行了化简、推导和求解,验证了传热传质方程组的合理性,并以不同温度的喷淋水对水蒸发冷却效果的影响为研究重点进行了理论研究。第四章主要针对不同温度的喷淋水对水蒸发冷却效果的影响进行了实验研究。利用风管式焓差法实验台对直接水蒸发冷却过程进行了空气流速u、水汽比μ、淋水温度tw对ηDEC影响的实验研究,利用实验所得数据拟合出了相应的效率公式和阻力公式,并进行了相应的分析,为标准《水蒸发冷却空调机组》的编制贡献微薄的力量。第五章基于提高温降幅度准则对水蒸发冷却的嵌套的适应性进行探讨,总结了六种基本结构的(?)转化方式和(?)效率特点；并建立了在特定情况下嵌套效率的计算方法。更多还原

【Abstract】 Energy efficiency in HVAC system which energy consumption is a large part in building energy consumption is very important for energy efficiency work. Water Evaporative Cooling (WEC) is one of the energy efficiency technologies urgently needed because of the "high efficiency" and "replacement". Supported by the National "11th Five-Year Plan" to support science and technology project of China (NO.2006BAJ04B04), this paper stress exergy analysis of virtual cycles of WEC technology and finding out the effect forηDEC by different temperature of spray water. The principle of Direct Water Evaporative Cooling (DWEC) and the heat and mass transfer process are analyzed based on other people’research production in this paper. The calculation model of WDWEC process is built and the system of equations is derived and simplified; the theoretical analysis and a series of experiments are put into practice to find the effect forηDEC by different temperature of spray water. The main contents are shown as following:In chapter 1, the basic principle of Engineering Thermodynamics and Heat Transfer Theory about WEC were introduced briefly, the extreme temperature of DWEC and IWEC were under discussion, especially the essence of two forms of extreme temperature.In chapter 2, the virtual cycle of DWEC was set up, and exergy analysis of working substance at each stage in virtual cycles was completed. By the way, the direction and amount of energy transfer were clearly indicated in the text. Optimization analysis of equipments and systerms’energy transfer process was done, and two criteria were built up to improve equipments and systerms’performance, in order to provide the theoretical basis for the later chapters.In chapter 3, the common process which use of recycled water for DWEC has been to expand, the effect forηDEC by different temperature of spray water is considered during the theoretical analysis of DWEC process. And the equation what give a scientific description of heat and mass transfer process is built up, the effect forηDEC by some different influence factors were discussed according to theoretical analysis based on the criteria of improving equipments and systerms’performance. Then the system of equations of heat and mass transfer process is derived, simplified and solved in the case of isenthalpic and cooling process to show the validity and rationality of calculation model. Focus on finding out the effect for performance of DWEC by different temperature of spray water according to theoretical analysis.In chapter 4, the main work is analyzing the effect forηDEC by different temperature of spray water according to experimental method. A series of experiments are done with pipes enthalpy potential method test bench to find the effect forηDEC by different air velocity, different water-gas ratio and different temperature of spray water. Based on fitted result of these experiments, we can get two fitted formulas aboutηDEC,Δp. All of this can provide supports to standard of Water Evaporative Cooling Air Conditioning Unit.In chapter 5, the adaptability of loop nests which called Multistage Evaporative Cooling was discussed according to theoretical analysis based on the criteria of improving the scale of temperature reductions. Both exergy conversion form and characteristic of exergy efficiency of six basic structures were sumed up, and the method of exergy efficiency calculate was given..更多还原