大空间分层空调与上部通风即时耦合方法研究

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摘要

随着全球能源消耗的日趋紧张，以及人民生活水平的不断提高，空调室内热

环境的舒适性、健康性以及空调运行的节能性等问题已经成为人们关注的焦点。

分层空调作为节能技术之一，早已在大空间建筑中得到了应用和推广。在此基础

上，为进一步降低空调能耗，改善室内热环境，研究最大限度地利用室外自然冷

源便是本文的研究重点。本文提出的分层空调与上部通风即时耦合的思想是基于

下部分层空调与上部通风同时运行的思想，利用室外自然冷源通过上部通风带走

或部分带走非空调区域滞留的热量，以减少空调能耗，这一课题的提出及其论文

研究成果，将为大空间建筑分层空调的节能运行提供参考。

建筑空调能耗与室内负荷密切相关，为更好地研究大空间建筑空调降耗的方

法，本文首先以世博大空间实验基地建筑为研究对象，围绕大空间建筑分层空调

负荷以及热转移量随各种影响因素的变化特性进行了一系列的理论计算与分析，

并对采用的计算方法进行了讨论。

为全面反映分层空调与上部通风即时耦合对大空间建筑室内热环境的影响规

律，结合生态楼建筑室内空气温度分布、围护结构内壁面温度、自然通风量等热

环境参数的测定结果，分析了在分层空调时上部通风与否的两种工况下室内热环

境，验证了上部通风与分层空调结合改善室内热环境的有效性，为上部通风有效

利用的理论研究提供了实验依据。

本文采用数学建模的方法，建立大空间简易分区模型来分析上部通风对室内

热环境的影响。该模型基于多区热质平衡原理，建立室内空气热质平衡方程，并

考虑建筑上部开口和室内热源等因素的影响，对方程进行相应修正，同时联立非

空调区壁面导热、对流、辐射耦合换热方程，计算得到非空调区的室内空气平均

温度和围护结构内壁面温度。利用其解作为分层空调负荷的计算条件，从而获得

上部通风对空调负荷的影响，为分层空调与上部通风即时耦合方法的应用研究提

供基础。文章以生态楼建筑测试工况为依据，采用该模型计算了测试工况下非空

调区的室内空气平均温度和壁面温度，结果表明，计算值与实测值误差低于 5%。

因此大空间建筑在分层空调与上部通风即时耦合时，大空间简易分区模型用于预

测其室内热环境是有效可行的。

根据夏季分层空调与上部通风即时耦合运行方案的设计思想，本文提出并确

定了切换温度的概念和计算方法，并对生态楼建筑进行应用分析，确定其夏季设

计工况下即时耦合运行的温度切换点：下切换点温度为 tw=22.8℃，上切换点

tw=34.8℃。同时，对切换状态点的影响因素和系统运行的节能性进行分析，由计

算结果得出，分层空调+上部通风的耦合运行方案节能效果显著，对于本文的生

态楼建筑而言，其能量节约率平均约 21%，最大可达 48%，且随着室外温度的降

低而增加。夏季上部通风利用后，空调总节能量为 1.32 万kWh，如系统能效比平

均按 COP＝2.5 计算，节电约 0.53 万度。综合表明，上部通风的利用有着很大的

应用潜力，不仅有利于降低建筑能耗，实现较好的节能效果，同时也有助于提高

室内空气品质。

本文主要围绕大空间上部通风与分层空调系统耦合运行的应用展开研究，通

过现场实测分析、理论模型建立与即时耦合应用研究相结合的方法得出了耦合运

行切换点，验证了大空间建筑上部通风应用具有较大的节能潜力，这将为大空间

建筑分层空调的节能运行提供理论基础和研究方法，具有实际工程指导意义。

关键词：大空间建筑分层空调+上部通风简易分区模型即时耦合

节能运行

ABSTRACT

With the growing tension of global energy consumption, as well as the continuous

improvement of people's living standards, whether the indoor air-conditioning thermal

environment is comfortable and healthful and air-conditioning operation is

energy-saving have become the focus of attention. Stratified air-conditioning as one of

energy-saving technology has been applied and promoted in the large space building.

On this basis, in order to further reduce air-conditioning energy consumption and

improve indoor thermal environment, the research on utilization of outdoor natural

cold resources to the maximum is the focus of this paper. In this paper, based on taking

both the lower ventilation and the upper stratified air-conditioning running into

consideration at the same time, the idea of bringing in hybrid of both the stratified

air-conditioning and the upper ventilation comes into being , and it can make use of

natural cold resources to take away some part of heat retention of non-air-conditioning

area through the upper ventilation to reduce the air-conditioning energy

consumption .The subject raised and research results will give a reference to

energy-saving running of large space building air-conditioning.

Building energy consumption is closely relevant to indoor air-conditioning load,

and in order to work out a better way of reducing energy consumption in

air-conditioning large space building, firstly the Expo building experimental base is

taken as an study object in this paper, and then a series of theoretical calculations and

analysis enclosing large space building air-conditioning load and variety characteristics

of the thermal transfer volume along with various factors are made, and lastly

discussions on calculation methods adopted are made.

To fully reflect the law of the impact of the stratified air-conditioning coupled

with the upper ventilation on thermal environment in the large space building ,

according to test results of indoor air temperature distribution of eco-building, in the

first place wall surface temperature of building envelope, natural ventilation volume,

and indoor thermal environment are analyzed under two conditions of the upper

ventilation or not at stratified air-conditioning ,and secondly the validity of the upper

ventilation and the stratified air-conditioning was proved, both of which provide a

experimental basis for theory research of upper ventilation validity .

In this paper, numerical simulation methods are adopted to establish a simple

zoning model of large space to analyze the influence of the upper ventilation to the

indoor thermal environment. The model is based on the multi-zone heat and mass

balance principle, and indoor air heat and mass balance equation is established and

made corresponding amendment according to such factors of the upper opening and

interior heat source,, simultaneously coupled with equations of wall heat conductivity,

convection, heat transfer, radiation of non-air-conditioning area, thereby the indoor air

average temperature and the envelope wall surface temperature of non-air-conditioning

area were gained through calculation. Then the effect of the upper ventilation to

air-conditioning load is got by taking above solution as the calculation conditions of

stratified air conditioning load of eco-building, which provides a basis for application

research of stratified air-conditioning and the upper ventilation. Average indoor air

temperature and wall temperature of the non-air-conditioned area under test conditions

by Eco-building model are calculated, the results show that the deviation between the

calculated values and measured is less than 5%. Therefore the simple zoning model in

large space is feasible and effective to predict the indoor thermal environment, when

adopting the stratified air-conditioning coupled with the upper ventilation in the large

space building.

According to the idea of stratified air-conditioning coupled with the upper

ventilation in summer, the concept of switch temperature is raised and its calculation

method is worked out in this paper , and an application analysis for eco-building is

made, then the temperature switch points of the coupling runing in summer design

conditions are determined: the lower switch point temperature tw=22.8℃, the

switching point tw=34.8℃. At the same time, analysis for the influence factors and

energy-saving effect of switch state point are carried out , results shows that the

energy-saving effect of stratified air-conditioning + upper ventilation is significant, its

average energy savings rate for the eco-building is about 21%, up to 48% to the

maximum, and it will rise when the outdoor temperature decreases.When upper

ventilation is used in summer, the total energy-saving volume of air conditioning is

13,200 kWh, if the average system energy efficiency ratio is calculated by COP = 2.5,

power-saving is about 5,300 kWh degrees. Comprehensive results show that the use of

the upper ventilation has a great application potential, and it not only reduces building

energy consumption but also realizes better energy efficiency, what`s more helps to

improve the indoor air quality.

In this paper, research on the application of the upper ventilation coupled with the

stratified air-conditioning system in large space is carried out, through analysis of the

field test and, the establishment of the theoretical model, and application of coupling

immediately method, the running switch point of coupling is obtained, and substantial

energy-saving potential of the upper ventilation in the large space building is verified,

it will provide a theoretical basis and research method for the stratified air-conditioning

in large space building ,therefore, it will have practical engineering significance.

Keywords: large space building, stratified air-conditioning+upper

ventilation, simple zoning model, coupling immediately,

energy-saving operation

中文摘要

ABSTRACT

第一章绪论 ····················································································· 1

§1.1 课题的来源及意义 ······································································ 1

§1.2 国内外研究现状 ········································································· 2

§1.2.1 大空间分层空调的研究 ··························································· 2

§1.2.2 大空间温度场的研究 ······························································ 3

§1.2.3 大空间自然通风的研究 ··························································· 5

§1.2.4 空调与通风耦合的研究 ··························································· 7

§1.2.5 空调系统节能运行的研究 ························································8

§1.2.6 大空间建筑现场实测的研究 ·····················································9

§1.3 本课题研究内容 ······································································· 10

§1.3.1 研究内容 ············································································11

§1.3.2 主要关键技术 ······································································11

第二章分层空调理论与热转移量特性研究 ··············································· 12

§2.1 分层空调冷负荷计算理论 ··························································· 12

§2.1.1 分层空调冷负荷计算特点 ······················································ 12

§2.1.2 分层空调冷负荷组成 ···························································· 13

§2.1.3 分层空调冷负荷计算方法 ······················································ 13

§2.2 分层空调冷负荷实例计算 ··························································· 15

§2.2.1 建筑概况 ············································································15

§2.2.2 空调设计参数 ······································································16

§2.2.3 分层空调夏季冷负荷计算 ······················································ 17

§2.2.4 夏季分层空调能量节约率 ······················································ 23

§2.3 分层空调热转移量特性分析 ························································ 24

§2.3.1 太阳辐射强度对热转移量的影响 ············································· 25

§2.3.2 室外温度对热转移量的影响 ··················································· 26

§2.3.3 通风量对热转移量的影响 ······················································ 27

§2.3.4 分层高度对热转移量的影响 ··················································· 28

§2.4 本章小结 ·················································································29

第三章分层空调与上部通风即时耦合室内热环境实测与分析 ······················· 30

§3.1 生态楼建筑及空调概况 ······························································ 30

§3.1.1 建筑概况 ············································································30

§3.1.2 空调概况 ············································································31

§3.2 生态楼现场测试与分析 ······························································ 31

§3.2.1 测定对象与测试工况 ···························································· 31

§3.2.2 室外环境测试方案与结果分析 ················································ 34

§3.2.3 中庭垂直方向温度测试方案与结果分析 ···································· 35

§3.2.4 围护结构内壁面温度测试方案与结果分析 ································· 39

§3.2.5 自然通风量测试方案与结果分析 ············································· 40

§3.2.6 工作区域水平温度测试方案与结果分析 ···································· 41

§3.3 本章小结 ·················································································43

第四章分层空调与上部通风即时耦合模型的建立与验证 ····························· 45

§4.1 大空间简易分区热质平衡模型 ····················································· 45

§4.1.1 大空间简易分区质平衡 ························································· 46

§4.1.2 大空间简易分区热平衡 ························································· 47

§4.1.3 大空间简易分区热质平衡模型的扩展 ······································· 48

§4.2 大空间简易分区热质交换模型 ····················································· 52

§4.2.1 非等温射流模型 ·································································· 52

§4.2.2 区域间热质交换模型 ···························································· 54

§4.3 自然通风模型 ·········································································· 55

§4.4 大空间简易分区壁面热平衡 ························································ 58

§4.4.1 壁面热平衡方程 ·································································· 59

§4.4.2 互辐射换热量的线性化计算 ··················································· 60

§4.4.3 导热传热外围护结构传热系数的计算 ······································· 60

§4.5 大空间简易分区热质平衡模型的求解 ············································ 62

§4.5.1 边界条件及各参数的确定 ······················································ 62

§4.5.2 热质平衡模型的求解方法 ······················································ 65

§4.6 应用生态楼实例模型计算 ··························································· 68

§4.6.1 计算用建筑物理模型 ···························································· 68

§4.6.2 计算用参数确定 ·································································· 68

§4.6.3 计算结果及分析 ·································································· 70

§4.7 本章小结 ·················································································71

第五章分层空调与上部通风即时耦合运行方法的研究与应用 ······················· 73

§5.1 方案基本设计思想 ···································································· 73

§5.2 切换温度的确定 ······································································· 74

§5.3 生态楼建筑空调通风即时耦合运行方案的确定 ································ 76

§5.4 通风切换温度影响因素分析 ························································ 78

§5.4.1 室内设计温度对切换温度的影响 ············································· 78

§5.4.2 通风量对切换温度的影响 ······················································ 79

§5.5 即时耦合运行方法节能分析 ························································· 80

§5.5.1 分层空调上部通风能量节约率 ················································ 80

§5.5.2 分层空调上部通风能耗节能量 ················································ 82

§5.6 本章小结 ·················································································83

第六章结论及展望 ··············································································85

§6.1 结论 ·······················································································85

§6.2 有待继续研究的内容 ································································· 87

参考文献 ··························································································· 89

在读期间公开发表的论文和承担科研项目及取得成果 ··································93

致谢 ································································································ 94

第一章绪论

§1.1 课题的来源及意义

近年来，随着北京奥运会的成功举办、上海世博会的临近以及城市建设的需

要，大空间建筑建设的步伐加快并逐渐成为城市建设的时代特征。大空间建筑室

内热环境的舒适性、健康性与空调运行的节能性如何和谐共处成为人们关注的主

要问题之一，这也将成为 21 世纪建筑环境研究和发展的一个方向，更是地球可持

续性发展的主要要素之一。

大空间建筑由于高度高、体积大、人员居留区高度远低于室内总高，空调能

耗往往远大于实际居住域所需能耗，其空调系统往往具有初投资高和运行能耗大

的特点[1]。如何降低能耗正成为人们日益关注的焦点。因此，分层空调作为一种

大空间空调处理方式已被国内外广泛采用，与全室空调相比，大约可节省冷负荷

30%左右[2]。

如今，在能源问题日益紧张的环境下，人们对建筑节能的意识不断提高，如

何最大限度地降低建筑能耗是暖通专业人士亟需完成的课题。目前解决建筑能源

问题主要从以下两方面着手：降低建筑能源消耗和利用可再生能源、清洁能源。

自然通风的利用不仅可以减少建筑一次能源的消耗量，而且使室内居住者有亲近

自然的感觉，更易于居住者接受。就目前来说，大空间建筑多采用分层空调的形

式，下部居住域进行空调，上部非空调区域的滞留热空气利用自然通风的形式带

走。因此利用自然通风改善室内空气品质，降低空调能耗逐渐成为空调节能技术

的一个研究方向。然而，自然通风的利用并非一直都有利，随室内外状态、全年

季节等因素的不同，它对降低能耗的作用有利有弊，为此深入研究大空间建筑通

风与空调耦合的运行方法，正确、合理地利用这一自然能源，变自然通风为有利

条件，以减少使用空调对环境的压力有着重要的意义。

本文的研究思想在于探讨如何充分利用室外自然空气冷源，最大限度地利用

通风带走分层空调上部非空调区域滞留的热量，从而减少非空调区域辐射热转移

量和对流热转移量对空调区域负荷的影响，同时满足人们对居住域舒适性的要求。

这一研究对于大空间建筑降低空调能耗、缩短空调运行时间具有重要的意义。

本课题在大空间建筑分层空调和通风理论研究成果的基础上，以世博专项子

课题“世博展厅建筑室内舒适性热环境与节能研究”为背景，将具有上部开口的、

典型侧喷送风方式的大空间建筑作为研究对象，合理地借助分层空调负荷与通风

大空间分层空调与上部通风即时耦合方法研究

量计算模型，结合建筑实例、采用数学建模和现场实测的方法相结合，分析室内

外空气状态、内部热源、开口特性等参数对切换温度的影响，提出上部通风与分

层空调即时耦合的运作模式，探讨在大空间建筑中如何更合理、准确、高效地利

用室外自然冷源，这不仅有利于提高室内空气品质，而且可以大大节约空调系统

运行的能耗，对大空间建筑空调通风系统的设计和运行提供参考。

§1.2 国内外研究现状

§1.2.1 大空间分层空调的研究

分层空调一般可以定义为，在高大空间两侧或单侧腰部设置送风喷口、下部

同侧均布回风口，运用多股平行非等温射流，将大空间建筑空间隔断为上下两部

分，仅对下部供冷，而上部较大空间不予空调或采用通风方式排除滞留的热量。

分层空调作为一种特殊的气流方式，于 60 年代后期出现在美国，后来又应用

于日本，如，美国格林维尔汽轮机厂、维尔明顿反应堆后处理厂、日本大型精密

机械加工场等[3]。

70 年代，日本小林满，宫川保之[3]等先后对大空间分层空调气流进行模拟试

验，总结了一些理论计算式，但未见用于工程实际。

79 年，美国堪萨斯大学 L. Gorton 和D. Ball 教授[3]等分别进行了分层空调负

荷和气流组织的研究，用简易数学模型进行了解析，但其所进行的假设使得其研

究成果与实际情况有一定的差距，用于实际工程的设计计算尚有一定的困难。

20 世纪 70 年代后，分层空调技术在我国开始有所应用。1979 年，由中国

建筑科学院空调所负责，组织机械工业部第二、六、七等设计院[4-5]参加进行了“高

大厂房分层空调技术研究”，课题研究于 1981 年提出了 “多股交叉非等温射流气

流组织计算”，“分层空调负荷计算”，“分层空调系统选择”等研究成果。为了综合

国内对于分层空调技术的研究成果，1993 年出版的《实用供热空调设计手册》对

分层空调的适用范围、空调形式、负荷计算、气流组织和系统形式做了详细介绍

并提出了不少计算公式。这是国内现在大空间分层空调设计的主要参考依据。

90 年代以后，湖南大学[4,6-7]，哈尔滨建筑大学[5]等分别采用数值模拟的方法

对一般分层空调和洁净分层空调气流进行模拟，取得了一定成果。西安交通大学

还对热风气流分层采暖进行了实验研究[8]。

2002 年，高军等[9-11]采用 CFD 方法对大空间分层空调下的温度场进行了模

拟，直观地分析了温度分布的特性，并从数值角度初步分析了多股射流运动的特

性。同时针对大空间分层空调负荷提出了一种简化计算模型，该模型可用于模拟

第一章绪论

大空间主流区与壁面的温度分布、主流区质量流动，可计算稳态条件下分层空调

负荷。

2004 年，李晓冬等[11]通过数值模拟研究了分层气流组织在冬夏季流场分布

特点，为大空间建筑暖通空调系统的节能和室内热环境的改善提供了依据。

2007 年，杨德福[12]以重庆地区某高大机械加工厂房分层空调为对象，采用

CFD 数值模拟与经验公式相结合的方法研究高大空间分层空调的对流热转移量，

并对设计参数进行了敏感性分析。

近几十年以来，分层空调技术无论国际国内，无论在其工程技术开发，还是

应用基础研究方面都取得了长足的进步。当然，这些研发成果还仅仅是初步的，

尚存在许多有待深入、完善的地方。例如，室内辐射热转移量和对流热转移量还

无法准确计算，部分计算方法的结果还不是很精确，适用范围也还十分有限。

实践证明，只对某一高度以下区域有空调要求的大空间建筑，采用分层空调

是一种经济、实用、有效的方式，在高大空间上部非空调区设置排风系统很有必

要，可以及时排走上部集聚的热量，减少顶棚室外热辐射对空调区的影响，从而

可以较好的保证下部空调区温、湿度要求。

§1.2.2 大空间温度场的研究

解决大空间分层空调负荷的理论计算问题的关键之一是大空间温度场和壁面

温度的模拟计算。大空间温度场的研究源于大空间建筑室内热环境分析的需要，

因为大空间建筑室内热舒适性环境很大程度上依赖于大空间建筑室内温度的垂直

分布[13]。80 年代以后，国外开始对此进行了研究。近年来，国内也逐渐开展了一

些研究工作。对大空间温度场的模拟主要有两种方法：CFD 数值模拟方法和简易

模型计算方法。

1）CFD 数值模拟方法

随着计算机发展和应用，质量、动量和热量守恒方程组的非线性求解问题已

经由计算流体力学（CFD）数值解代替，模拟中采用的数学模型主要是零方程模

型，k-ε两方程模型、DSM 模型、ASM 模型、LES 模型等[14-20]。

国内一般采用 k-ε两方程模型，这一模型于 70 年代中期由 Launder 和Spalding

将雷诺应力作时均处理推出[20]，在大空间温度场、速度场数值模拟中应用较早[13]，

但是它将紊流特性解释为各向同性，计算精度有一定限制。1998 年，清华大学提

出一种改进的零方程模型，并将其应用到其开发的软件 STACH-3 中，在非等温

送风及强迫对流和自然对流混合情况下，取得了较好的结果，与实验相比，温度

的最大差别为 0.8℃[14]。

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摘要：

摘要随着全球能源消耗的日趋紧张，以及人民生活水平的不断提高，空调室内热环境的舒适性、健康性以及空调运行的节能性等问题已经成为人们关注的焦点。分层空调作为节能技术之一，早已在大空间建筑中得到了应用和推广。在此基础上，为进一步降低空调能耗，改善室内热环境，研究最大限度地利用室外自然冷源便是本文的研究重点。本文提出的分层空调与上部通风即时耦合的思想是基于下部分层空调与上部通风同时运行的思想，利用室外自然冷源通过上部通风带走或部分带走非空调区域滞留的热量，以减少空调能耗，这一课题的提出及其论文研究成果，将为大空间建筑分层空调的节能运行提供参考。建筑空调能耗与室内负荷密切相关，为更好地研究大空间建筑空调...

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