高压喷雾冷却机理及在世博轴应用的试验研究

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摘要

喷雾降温技术是通过细小雾滴蒸发达到降低环境温度的一种技术。为了使

2010 年上海世博会更好地应用喷雾降温技术，更深入地进行喷雾降温理论研究，

论文以高压喷雾系统为研究对象，建立了喷雾过程中雾滴传质模型，并针对该系

统在上海世博轴 10m 标高平台上的应用效果及其系统运行特性进行实测，对所建

模型进行实验验证。

本文根据传质基本原理，建立了雾滴在高压喷射过程中环境空气降温计算模

型，利用此模型可计算喷雾区域环境温度和湿度。在实验条件下，经理论与试验

结果比较，温度平均偏差为 0.63℃，含湿量平均偏差 0.59g/kg，计算值与实测值吻

合较好。以此理论模型为基础，计算得到喷雾环境的温湿度场分布，结果表明，

背景环境空气温度越高，相对湿度越低，喷雾降温效果越明显，在距离喷嘴 10 米

的区域内，当相对湿度为 40%时，空气温度为 30℃和 38℃时，平均温降幅度分别

为2.39℃、3.16℃，当相对湿度为 80%时，空气温度为 38℃时，平均温降幅度仅

为0.78℃。针对日本学者经实验得出的喷雾降温适用于温度大于 30℃、相对湿度

小于 70%的气象条件结果，利用模型计算得出，在该气象极限值条件下，工作压

力为 5MPa 时，喷雾区域距喷嘴 3.2m 范围内的空气降温幅度均高于 1℃，论文还

进行了不同喷雾压力条件时喷雾降温效果及其范围的理论计算。

2009 年针对高压喷雾系统在上海地区应用的可行性，根据世博轴 10m 标高平

台设计高压喷雾实验系统，论文进行了一系列系统运行特性的试验研究，并对不

同喷雾压力、不同喷嘴组合时喷雾温降效果进行了对比试验。结果表明，高压喷

雾系统具有用水量少、低能耗、系统稳定的特点，且喷嘴数量为 24 的喷雾柱能使

喷雾区域 8m 范围内的温降平均幅度达 1-3℃。

世博会举行期间，本课题对世博轴 10m 标高平台上高压喷雾系统实际应用效

果进行了现场实测。结果表明，高压喷雾系统的降温效果明显，且环境温度越高，

相对湿度越低，喷雾降温效果就越大。在极端高温 40℃的气象条件下，在喷雾柱

下风向距离 10m 范围内，喷雾降温所实现的降温效果最高达 9℃，平均达 2-3℃。

论文还利用 WBGT 室外热环境评价指标对喷雾环境进行评价，结果表明，在喷雾

区域 10m 范围内，环境 WBGT 值可降低 1-4e。

论文所建空气降温计算模型，可以理论计算喷雾区域温湿度场分布及喷雾降

温效果，改变了以往通过实验了解降温效果的现状，为进一步研究喷雾降温效果、

改进喷雾降温技术提供理论基础。论文对于高压喷雾系统运行的特性试验研究，

以及在上海地区的现场实测结果，对于实际工程设计和应用提供了一定的参考价

值。

关键词：高压喷雾降温系统世博轴传质模型降温效果试验研究

III

ABSTRACT

Spray system is widely used in the outdoor environment in 2005 Aichi Expo Japan.

To some extent it improved the microenvironment. Avoiding heat stroke and made

people more comfortable. The 2010 Shanghai World Expo runs through the hot summer

months, then conditions of high temperature and humidity in Shanghai, whether the

spray cooling technology is applicable or not is to be further explored. The study of the

spray cooling technology on improving human comfort at home and abroad is not so

much, and the theory of spray distribution of temperature and humidity in open space is

lacking. With the advantages of small size droplets and rapid evaporation,

High-pressure spray system brings little burden of humidity. Studying on the

high-pressure spray system, droplet mass transfer model during spraying was

established. And to verify this model, the system was tested on the Expo-axis platform

which was 10 meters high.

The mass transfer model of droplet swarming in the air was established on the base

of the theory of the droplet evaporation in the air, and then was verified through testing.

Using this model, the ambient temperature and humidity in spray zone can be calculated.

Under the experimental conditions, through the comparison of theoretical and

experimental results, the maximum temperature deviation was 4.8% and the average

was 1.5%; the maximum moisture deviation was 6.7%, the average was 0.7%,

calculated and measured values have a good degree of agreement. Based on the model,

the spray distribution of temperature and humidity in environment was calculated, the

results show that higher air temperature, and lower relative humidity made the cooling

system more effective. At a distance of 10 meters from the nozzle, with the relative

humidity of 40%, when the air temperature was 30 ℃and 38 ℃,the regional average

rate of temperature drop was 2.39℃and 3.16℃, when the relative humidity was 80%

and the air temperature is 38 ℃, the regional average temperature dropped by only

0.78 ℃. With the results of Japanese scholars, the spray technology applicable

temperature is more than 30℃, when the relative humidity is less than 70%, by using

the model calculated, the air temperature drop range is higher than 1 ℃within the

distance of 3.2m from the nozzle.

In 2009, to study the application of the high-pressure spray system in Shanghai,

series of researching tests on operating characteristics of this system had been done on

the Expo-axis platform which was 10 meters high, including testing the spray volume

under different pressures and different nozzle combination. The results showed that the

high-pressure spray system used less water and less power consumption, and it had

better system stability. The column with spray nozzle numbers of 24 can make a

temperature drop of 1-3 ℃in average in spray area.

During the expo, a field measurement had been done to test the effect of

high-pressure spray system used on the Expo-axis platform which was 10 meters high.

Testing result showed that higher ambient temperature and lower relative humidity

made greater cooling effect. Under the extreme weather conditions of high temperature

for 40 ℃, the largest temperature drop is nearly 9 ℃within the distance of 10m from

the nozzle, the average 2-3 ℃. This paper also used WBGT index to evaluate spray

environment. The result showed that the WBGT index drop is 1 ~ 4e.

According to the mass transfer model, the distribution of the spray area

temperature and humidity, and cooling temperature drop can be calculated, which has

changed the way to study the cooling effect by experiment before. That also provides

theoretical basis for further research on spray cooling effect and improving spray

cooling technology. The study on operation characteristic of the high-pressured spray

system, as well as the field measured results in Shanghai, supports certain reference

value for designing and application in practical engineering.

Key Words: High-pressure spray system, Expo axis, Mass-

transfer mode, Cooling effectiveness, Experimental study

摘要

ABSTRACT

第一章绪论 .....................................................................................................................1

§1.1 课题研究背景 ......................................................................................................1

§1.2 国内外喷雾降温技术应用及研究进展 ..............................................................2

§1.2.1 液滴雾化技术应用领域 ............................................................................2

§1.2.2 液滴特性及机理研究 ................................................................................3

§1.2.3 喷雾工程应用研究 ....................................................................................4

§1.2.4 国内外喷雾降温技术应用现状 ................................................................6

§1.3 课题研究目的与研究内容 ..................................................................................6

§1.4 课题研究方案 ......................................................................................................7

第二章喷雾过程中空气降温计算模型建立及验证 .....................................................8

§2.1 雾滴在喷雾过程中传质模型的建立 .................................................................8

§2.1.1 雾滴质传递过程机理分析 .......................................................................8

§2.1.2 湿空气中雾滴蒸发速率模型建立 ...........................................................9

§2.1.3 喷雾环境中湿空气降温模型建立 .........................................................12

§2.2 喷雾过程中空气降温模型验证 .......................................................................15

§2.2.1 主要参数的选取 .....................................................................................16

§2.2.2 喷雾过程中湿空气温降湿增实验验证 .................................................17

§2.3 喷雾过程中湿空气特性计算及分析 ...............................................................19

§2.3.1 不同环境湿度时喷雾降温特性计算及分析 .........................................19

§2.3.2 不同环境温度时喷雾降温特性计算及分析 .........................................20

§2.3.3 气象条件极限值喷雾降温特性分析及计算 ..........................................22

§2.4 小结 ....................................................................................................................24

第三章高压喷雾系统运行特性试验研究 ...................................................................26

§3.1 高压喷雾试验系统概况 ...................................................................................26

§3.2 世博轴高压喷雾降温效果特性试验方法 .......................................................28

§3.2.1 试验目的 .................................................................................................28

§3.2.2 主要测试内容 .........................................................................................28

§3.2.3 主要测试仪器 ..........................................................................................29

§3.2.4 测点布置 .................................................................................................30

§3.3 喷雾系统运行特性试验结果与分析 ...............................................................31

§3.3.1 不同喷雾压力下喷雾量特性试验 .........................................................31

§3.3.2 不同喷雾压力下喷雾系统能耗试验 .....................................................32

§3.3.3 不同喷雾压力下喷雾降温特性试验 .....................................................33

§3.3.4 耐久性试验 .............................................................................................39

§3.4 小结 ....................................................................................................................40

第四章世博展期间高压喷雾系统应用降温效果实测及分析 ...................................42

§4.1 世博轴高压喷雾降温系统方案 .......................................................................42

§4.1.1 喷雾柱布置方案 .....................................................................................42

§4.1.2 世博轴高压喷雾降温系统 .....................................................................43

§4.2 高压喷雾系统降温效果实测方案 ...................................................................44

§4.2.1 试验目的 .................................................................................................44

§4.2.2 主要测试内容 .........................................................................................44

§4.2.3 测点布置 .................................................................................................44

§4.3 试验结果及分析 ...............................................................................................45

§4.3.1 环境参数测定结果 ..................................................................................45

§4.3.2 喷雾降温时频特性及分析 ......................................................................47

§4.3.3 喷雾湿增时频特性及分析 ......................................................................48

§4.3.4 喷雾降温范围特性试验结果 ..................................................................50

§4.3.5 不同气象条件下高压喷雾降温效果对比 ..............................................51

§4.4 喷雾环境下 WBGT 评价 ................................................................................. 52

§4.4.1 WBGT 评价方法 ..................................................................................... 52

§4.4.2 喷雾环境下 WBGT 评价结果及分析 ................................................... 53

§4.5 小结 ...................................................................................................................54

第五章结论与展望 .......................................................................................................56

§5.1 研究结论 ...........................................................................................................56

§5.2 课题展望 ...........................................................................................................57

参考文献 .........................................................................................................................59

在读期间公开发表的论文和承担科研成果 .................................................................63

致谢 ...........................................................................................................................64

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摘要：

I摘要喷雾降温技术是通过细小雾滴蒸发达到降低环境温度的一种技术。为了使2010年上海世博会更好地应用喷雾降温技术，更深入地进行喷雾降温理论研究，论文以高压喷雾系统为研究对象，建立了喷雾过程中雾滴传质模型，并针对该系统在上海世博轴10m标高平台上的应用效果及其系统运行特性进行实测，对所建模型进行实验验证。本文根据传质基本原理，建立了雾滴在高压喷射过程中环境空气降温计算模型，利用此模型可计算喷雾区域环境温度和湿度。在实验条件下，经理论与试验结果比较，温度平均偏差为0.63℃，含湿量平均偏差0.59g/kg，计算值与实测值吻合较好。以此理论模型为基础，计算得到喷雾环境的温湿度场分布，结果表明，背景环...

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