基于湿膜的露点式蒸发冷却系统研究
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摘 要
随着人类环境保护意识、对环保要求标准和对居住环境舒适度要求的不断提高，
建筑制冷技术的革新再次成为各科研领域的热门话题。而在减少或不对自然环境
造成破坏的前提下，将建筑与自然的完美结合将是各行业科研工作者所追求的终
极目标。伴随此理念诞生的新技术和对原有技术的革新层出不穷。蒸发冷却技术就
是其中之一。它即是古老的又是新兴的，它的基础理论很早就被人类发现并利用，
但真正结合现代科学技术的研究和运用的时间并不长，还有很多与热质交换相关
的理论问题需要我们继续深入的研究探讨。同时露点式蒸发冷却的制冷设备还存
在很多不足，这方面的课题研究工作在世界范围内一直都在进行。在我国，对露点
式蒸发冷却的研究还处于初期阶段。
本课题主要研究露点式蒸发冷却系统。论文作者设计研发了一套露点式蒸发冷
却装置。通过实验测试不同进口温度、湿度和不同组成形式下的热湿交换效果，研
究进口参数对露点式蒸发冷却系统性能的影响，比较不同通道组合形式的热质交
换。
首先，本文阐述了实验装置的设计思路及具体参数。实验台通过不同的布水方
式可以实现四种不同形式的实验，只要在不同的通道布好测点就可以完成不同蒸
发冷却方式的对比试验。论文作者针对目前市场上较常见的材料进行了物性的对
比分析，并选取一种作为本文实验台所用的填料材料。总结了影响热质传递程度的
9大要素包括：水膜层的温度、入口空气的温度、入口空气的湿度等。对于其中的
核心问题之一的水膜材料来说最关键的为比表面积、润湿保水性能和热力性能。
其次，本文分析了不同布水运行方式、不同条件参数下各种工况运行的特点和
温度场分布、湿度场分布等。然后阐述了两种用于评价蒸发冷却器性能的指标，并
利用这两种指标比较了实验中两种布水运行方式的效率和多级模拟中几种系统形
式的效率。实验数据表明，全系统布水方式比半系统布水方式的冷却效果要好。而
在相同的布水方式和运行参数的情况下，低湿度的时候干通道进出口温度差会比
高湿度时高，但效率反而会比高湿度的时候低。
再次，本文对露点式蒸发冷却进行了模拟研究。经过模型搭建及参数调整，将
模拟误差控制在 10%以内。除了传热过程的模拟，本文还进行了传质过程的模拟，
即水的蒸发过程模拟。根据模拟所得结果，详细描述了三种模型的模拟结果，从压
力场、流动场、温度场、湿度场等不同方面分别进行了对比分析和说明，同时依据
模拟结果分析了流动场、温度场、湿度场之间的耦合关系，结论表明微尺寸蒸发冷
却器半流量多级冷却的效果是最好的。在入口空气参数、运行速度相同的情况下，
冷却到同样的温度，微尺寸模型所需要的级数更少，效率更高。
最后，通过用上海地区实际参数的计算结果提出了将露点蒸发冷却系统与除湿
系统结合使用以达到理想结果的假设。并依据实验和模拟数据，针对本实验台提出
了优化方案和改进方向。
关键词：蒸发冷却 实验研究 数值模拟 露点式循环 干湿通道
ABSTRACT
With the improvement of environmental protection consciousness, the environmental
protection standards and the requirement of comfort living environment, air-cooling
technology’s innovation has become a hot topic in the field of scientific research once
again. Under the premise of reducing or on damage for the natural environment, the
ultimate goal of scientific researchers is perfect combination of architecture and nature.
With this concept, new technology and innovation of the original technology is emerging
in endlessly. Evaporative cooling technology is one of them. It is antiquity and newly-
developing, its basic theory was discovered and used long before, but combined with
modern science and technology research is not long. There are a lot of heat and mass
transfer and related theory problems we need to further study. Also dew point evaporative
cooling’s equipment also has many shortcomings, the research work have been no stop in
the world. In the domestic, the study of dew point evaporative cooling is still in its early
stage.
This paper is about the dew point evaporative cooling technology. A set of dew point
evaporative cooling unit has been developed independently. Through testing the data
under different inlet temperature, humidity and the heat transfer effect to study different
inlet parameters’ influent on this unit cooling effect, which can compare the heat transfer
effect of different channel form.
Firstly, this paper introduces the design of experiment device and specific parameters.
By different ways of cloth water, it can realize the four different forms of experiment. In
addition, before building test bench, comparison study of the packing materials used for
the test bench has been made, common materials in present market are analyzed in
comparison of physical properties, and a packing material has been selected and used on
the test bench. The nine main factors that affect the degree of thermal and mass transfer
have been summarized, which include the temperature of the water film layer, the inlet
air temperature, the inlet air humidity and so on. For one of the core issues water film
materials, the main factors are the specific surface area, water-retaining property, thermal
performance.
Secondly, different way of water distribution parameters under different conditions,
operation characteristics and temperature distribution under various working conditions,
etc. have been analyzed in this paper. Then two indexes for evaluating the performance
of evaporative cooler have been introduced, Comparison of the two kinds of cloth water
operation efficiency and the efficiency of multi-stage simulation system types using these
two indexes has been made. Experimental data show that the whole system water
distribution mode is better than half system water distribution mode of cooling effect.
And in the same way of the water distribution and under the same condition of operation
parameters, the dry channel import and export temperature difference is higher in low
humidity, but the efficiency is lower than the high humidity.
Thirdly, the simulation research of the dew point evaporative cooling has been made
in this paper. Through the model building and parameter adjustment, the simulation error
be controlled less than 10%. In addition to the heat transfer process of simulation, this
article also has carried on the simulation of mass transfer, the water evaporation process
simulation. According to the simulation results, the simulation results of the three models,
the pressure field, flow field, temperature field and humidity field has been described in
detail, different aspects has carried on the comparative analysis and illustrate respectively.
At the same time, the results of simulation analysis of the flow field, temperature field
and humidity field coupling relationship show that the micro size half speed multi-stage
evaporation cooler cooling effect is the best. Under the same condition of speed, number
of cooling stages and inlet air parameters, the micro size required less stages, efficiency
is higher, when cooling to the same temperature.
Finally, according the calculation results for Shanghai area actual parameters, the
combination of dew point evaporative cooling and dehumidification system is put
forward to achieve the ideal result. And on the basis of the experimental and simulation
data, this paper put forward the optimization scheme for this test bench and the
improvement direction.
Key Words: Evaporative Cooling, Experimental Study, Numerical
Simulation, Dew Point Cycle, Dry-Wet Channel
目 录
中文摘要
ABSTRACT
第一章 绪论 ................................................................................................................. 1
§1.1 课题研究背景 ............................................................................................... 1
§1.1.1 蒸发冷却技术的发展历史 ............................................................... 1
§1.1.2 露点式蒸发冷却技术的提出及研究 ............................................... 1
§1.1.3 蒸发冷却技术在空气调节领域的应用 ........................................... 2
§1.2 国内外研究现状 .......................................................................................... 3
§1.2.1 露点式蒸发冷却结构形式的研究 ................................................... 3
§1.2.2 露点式蒸发冷却膜材料的研究 ....................................................... 4
§1.3 本文的内容和意义 ...................................................................................... 6
第二章 露点式蒸发冷却的理论 ................................................................................. 7
§2.1 直接式蒸发冷却的原理 .............................................................................. 7
§2.2 间接式蒸发冷却的原理 .............................................................................. 8
§2.3 露点式蒸发冷却的原理 ............................................................................ 10
§2.4 热质传递的耦合作用 ................................................................................ 12
§2.5 影响空气与水之间热质交换的主要因素 ................................................ 12
§2.6 水膜材料的性能对换热过程的影响 ........................................................ 13
§2.7 本章小结 .................................................................................................... 14
第三章 露点式蒸发冷却实验系统 ........................................................................... 15
§3.1 实验概述 .................................................................................................... 15
§3.2 实验辅助系统 ............................................................................................ 16
§3.3 露点式蒸发冷却器实验装置 .................................................................... 16
§3.3.1 设计思路 ......................................................................................... 16
§3.3.2 实验装置主体结构 ......................................................................... 17
§3.3.3 实验台运行流程及组合方式 ......................................................... 20
§3.3.3.1 实验台运行流程 .................................................................. 20
§3.3.3.2 组合方式 .............................................................................. 20
§3.3.4 形成水膜的填料选取 ..................................................................... 21
§3.4 实验台数据测量与采集 ............................................................................ 22
§3.4.1 温度的测量 ..................................................................................... 22
§3.4.2 湿度的测量 ..................................................................................... 23
§3.4.3 速度的测量 ..................................................................................... 24
§3.4.4 数据采集 ......................................................................................... 24
§3.5 实验步骤与内容 ........................................................................................ 25
§3.5.1 实验步骤 ......................................................................................... 25
§3.5.2 实验工况 ......................................................................................... 26
§3.6 本章小结 .................................................................................................... 27
第四章 露点式蒸发冷却系统的性能模拟 ............................................................... 28
§4.1 CFD 数值模拟方法介绍 ........................................................................... 28
§4.1.1 CFD 简介 ......................................................................................... 28
§4.1.2 常用的 CFD 软件简介 .................................................................. 28
§4 .1.3 模拟和计算软件及步骤 ................................................................. 28
§4.1.3.1 Fluent14.5 新特点 ................................................................. 29
§4.1.3.2 CFD 数值模拟步骤 .............................................................. 29
§4.2 数值方法 .................................................................................................... 32
§4.2 建立模型划分网格 .................................................................................... 33
§4.2.1 物理模型 ......................................................................................... 33
§4.2.2 网格划分 ......................................................................................... 34
§4.3 物理边界条件和初始条件 ........................................................................ 36
§4.4 数值模拟结果 ............................................................................................ 37
§4.4.1 整体模型研究 .................................................................................. 38
§4.4.1.1 压力分布 .............................................................................. 38
§4.4.1.2 流场分布 .............................................................................. 40
§4.4.1.3 湍流动能分布 ...................................................................... 41
§4.4.2 实际尺寸模型研究 ......................................................................... 42
§4.4.2.1 一级冷却 ............................................................................... 42
§4.4.2.2 多级冷却 .............................................................................. 51
§4.4.3 微尺寸模型研究 ............................................................................. 55
§4.4.3.1 温度分布 ............................................................................... 56
§4.4.3.2 湿度分布 ............................................................................... 58
§4.5 温度场、湿度场和速度场的耦合作用分析 ............................................ 63
§4.6 本章小结 .................................................................................................... 64
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：96 页
大小：9.62MB
格式：PDF
时间：2025-01-09
