基于缩尺模型的大空间下送风室内热环境及对流热转移负荷研究 pdf
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摘 要
随着国民经济的发展以及建筑技术的进步，国民对物质、文化生活均有了更
高的追求，因而体育馆、商场等大空间公共建筑、高大厂房等越来越多，其建筑
形式上也越来越多样。由于大空间建筑的特殊性，采用分层空调是较为经济合理
的选择。
大空间建筑分层空调的气流组织、室内热环境、空调负荷的研究，是大空间
分层空调研究中最重要的三个部分。其中气流组织和室内热环境对人员舒适度等
具有很大的影响，已引起国内外学者的广泛关注。大空间建筑的负荷计算对于设
备选用以及建筑节能具有非常重要的作用，目前国内大部分大空间建筑都采用喷
口送风的气流组织形式，设计规范中的计算方法也多是针对喷口送风，对于近年
来应用逐渐广泛的下送中回分层空调，其负荷计算方法在研究领域中尚未引起足
够的重视，更需要广泛、深入的研究。大空间室内热环境与其室内冷负荷之间有
着密不可分的联系，现有的文献中缺乏二者结合的研究，本文采用理论与实验结
合的方式，对大空间下送中回空调形式下的热环境及其对流热转移负荷进行研
究。
本文以上海理工大学大空间室内热环境实验基地为研究对象，通过应用相似
原理，设计并搭建空气缩尺模型实验台，进行缩尺模型与原型室内热环境对照实验、
室内热环境及对流热转移负荷实验；针对与实际大空间下送中回建筑热环境现场
实测对照的缩尺模型实验结果，分析模型实验与实际建筑实测结果的吻合度与模
型实验各相似比例尺等主要因素的影响特点，提出大空间下送中回缩尺模型实验
工况设计的建议；根据缩尺模型热环境实验结果，分析大空间下送中回分层空调室
内热环境的特征，为下送中回分层空调设计提供一定的依据；以空调区和非空调区
空气热平衡为基础，结合课题组对回风口风量占比的研究，建立大空间建筑下送中
回分层空调对流热转移负荷计算方法，并 针对缩尺模型对象，用模型实验结果进行
验证。利用论文提出的计算方法，针对研究对象，研究大空间建筑下送中回分层空
调对流热转移负荷特性。
本文通过理论和实验研究，得出以下结论：大空间建筑下送中回缩尺模型实验
的设计需要以阿基米德数 Ar 为主要准则数，同时应在条件允许的情况下尽量在 Re
自模区内接近原型的雷诺数 Re，Re 数越接近原型，模型实验室内热环境越接近原
型室内热环境。只考虑 Ar 数和仅要求 Re 数在自模区的方法会造成较大偏差。在
假定屋顶热量占室内总负荷 45%时，模型空调区的室内热环境与原型接近程度好
于非空调区的接近程度。在假定屋顶热量占室内总负荷的 75%时，模型非空调区
的垂直温度梯度更接近原型。大空间下送中回分层空调室内热环境垂直方向上可
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以分为三段，即送风区，回风区与热滞留区。其中不同工况下，回风区的无量纲温
度梯度变化很小，送风区无量纲温度梯度变化次之，热滞留区的无量纲温度梯度则
变化较大。以往进行大空间分层空调设计时参考的《实用供热空调设计手册》中对
于大空间建筑分层空调负荷的计算方法对于下送中回形式的分层空调并不适用，
文中提出的基于分区热平衡及回风占比的对流热转移负荷计算方法可以计算空调
区、非空调区特征温度，以及房间的对流热转移负荷。其中空调区特征温度与实测
空调区垂直温度平均值之间的误差在 8%以内，非空调区特征温度与实测非空调区
垂直温度平均值之间的误差也在 8%以内。对流热转移负荷计算值与实验值之间的
误差大部分在 15%以内，认为其可以用于计算大空间下送中回分层空调缩尺模型
的对流热转移负荷计算。大空间建筑下送中回分层空调的室内热环境、空调总负荷、
对流热转移负荷受送风参数和室外参数的共同作用，在室外参数一定的情况下，可
以通过文中总结的规律调整送风参数使得室内热环境达到期望值。
关键词：大空间 分层空调 下送中回 缩尺模型 热环境 对流热
转移负荷
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ABSTRACT
With the progress of national economics and architectural technology, Chinese
residents have developed higher taste for material and culture, thus leading to a larger
number of large space buildings such as factories and shopping malls with a wider range
of styles. Due to the specialty of the geometry, it is economical to equip large space
buildings with stratified air conditioning systems.
The air distribution, thermal environment and the space cooling load are the three
most important issues in the research field of stratified air conditioning systems. Among
the three issues, air distribution and thermal environment have distinct influence on the
comfort of people, and have caught the attention of many researchers at home and aboard.
On the other hand, the space cooling load of large space building is key to equipment
selection and building energy saving. Because most large space buildings in China are
equipped with nozzles to supply air, and the calculation methods of space load are targeted
for this kind of stratified air conditioning system. When it comes to the stratified air
conditioning system with low-sidewall air supply and middle air return, the space load
calculation method is lack of attention, and wider and deeper research is long overdue.
The space cooling load is strongly associated with the thermal environment of large space
building, but there is still absence of the combination of the two aspects in existent
researches. This paper studies the thermal environment and the convective heat transfer
of the stratified air conditioning system with low-sidewall air supply and middle air return
in both theoretical and experimental aspects.
This paper took the similarity theory as guide, designed and built a reduced-scale
model based on the large space experimental site in University of Shanghai for Science
and Technology. The thermal environment contrast experiments between the model and
the prototype have been conducted in the model. The thermal environment and convective
heat transfer experiments have also been conducted. Based on the results of the contrast
experiments, the coincidence between the model and the prototype have been analyzed,
and the influence of the scale ratios are explored. The suggestions of the model
experiment design have been proposed based on the analysis. The characteristics of the
thermal environment of the stratified air conditioning system with low-sidewall air supply
and middle air return are analyzed based on the thermal environment experiment results.
A convective heat transfer calculation method has been built on the thermal equilibrium
of the air conditioned zone and non-air-conditioned zone, and the air return volume ratio
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calculation method which was explored by another researcher in the research group
previously. The calculation method is validated by the experiments conducted in the
model. Using the calculation method, this paper has also probed into the characteristics
of the convective heat transfer of the stratified air conditioning system with low-sidewall
air supply and middle air return.
With theoretical and experimental research, some conclusions have been achieved.
First, Ar number should be regarded as the dominant principle number when designing
the model experiment for large space building with low-sidewall air supply and middle
air return, and Re number of the model experiment should be as close to the prototype
experiment as possible when it is in the self-similarity zone. The less the difference of the
Re number, the better coincidence of the thermal environment. When Ar numbers are
made the same in model and the prototype, and the Re numbers are only kept in self-
similarity zone, the thermal environment of the model will deviate from the prototype to
some extent. Second, when the heat volume of the roof accounts for 45% of the total heat
volume of the room, the thermal environment of air-conditioned zone in the model is
closer to the prototype than that in the non-air-conditioned zone. While when the heat
volume of the roof accounts for 75% of the total heat volume of the room, the vertical
temperature distribution is closer to the prototype. Third, the thermal environment of the
stratified air conditioned room can be divided into three parts vertically, namely air supply
zone, air return zone and heat stagnant zone. Under different experiment conditions, the
dimensionless temperature gradient varies in a small range in the air return zone, while it
varies in a larger range in the air supply zone, in the largest range in the heat stagnant
zone. Forth, the space cooling load calculation method proposed in the handbook is not
suitable for the stratified air conditioned room with low-sidewall air supply and middle
air return, and the method proposed in this paper which based on the zonal heat
equilibrium and air return volume ratio can be used to calculate the temperatures of the
air-conditioned zone, non-air-conditioned zone, and the convective heat transfer in this
kind of building. The calculated temperature of the air-conditioned zone has a deviation
less than 8% to the experimental vertical temperature average value, the temperature
deviation of the non-air-conditioned zone is less than 8% as well. The calculated
convective heat transfer has a deviation less than 15% to the experimental data in most
experimental conditions, thus the method is regarded suitable for the reduced-scale model
of the large space building with this kind of stratified air conditioning system. Fifth, the
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thermal environment, space cooling load, convective heat transfer are subjected to the
supply air parameters and the outdoor climate parameters. When the outdoor climate
parameters are identified, thermal environment can be controlled as expected according
to the pattern described in the paper.
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Key Word: large space, stratified air conditioning system, low-sidewall
air supply and middle air return, reduced-scale model,
thermal environment, convective heat transfer
目 录
摘 要 ............................................................................................................................... I
ABSTRACT ................................................................................................................... III
第一章 绪论 .................................................................................................................... 1
1.1 课题研究背景及意义 ........................................................................................... 1
1.2 国内外研究现状 ................................................................................................... 2
1.2.1 模型实验在室内热环境中的应用 ................................................................. 2
1.2.2 置换通风及下送风室内热环境研究 ............................................................. 4
1.2.3 大空间建筑分层空调负荷计算研究 ............................................................. 6
1.3 本文主要研究内容 ................................................................................................ 8
第二章 热环境缩尺模型实验台简介及缩尺比例确定 .............................................. 10
2.1 相似原理在下送中回分层空调室内热环境中的应用 ..................................... 10
2.1.1 相似原理的演绎过程及其应用 ................................................................... 10
2.1.2 大空间下送中回缩尺模型对流传热微分方程及相似准则数的推导 ....... 11
2.1.3 下送中回分层空调房间缩尺模型各比例尺的确定方法 ........................... 15
2.2 缩尺模型实验台缩尺比例设计计算 ................................................................. 16
2.2.1 大空间实验基地简介 ................................................................................... 16
2.2.2 缩尺模型实验台各比例尺关联及其计算 ................................................... 17
2.3 实验台测试系统概况及仪器标定 ..................................................................... 20
2.3.1 实验台测试系统概况 ................................................................................... 20
2.3.2 温度传感器标定 ........................................................................................... 23
第三章 缩尺模型下送中回室内热环境实验研究 ...................................................... 25
3.1 实验方案 ............................................................................................................. 25
3.1.1 实验测点布置 ............................................................................................... 25
3.1.2 缩尺模型实验工况设计 ............................................................................... 30
3.2 预实验及其结果分析 ......................................................................................... 35
3.2.1 壁面温度及热流密度代表测点的预实验研究 ........................................... 35
3.2.2 实验室风量与热量平衡预实验 ................................................................... 38
3.3 原型与模型热环境对比实验 ............................................................................. 39
3.3.1 室内垂直温度对比分析 ............................................................................... 39
3.3.2 下送中回缩尺模型实验缺陷分析 ............................................................... 44
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：85 页
大小：4.7MB
格式：PDF
时间：2025-01-09
