大空间建筑分层空调辐射转移负荷计算方法研究
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摘 要
考虑降低建筑能耗与提高室内空气品质，大空间建筑常采用分层空调。分层
空调是指仅对大空间建筑下部人员居留区进行空调，而对上部空间不进行空调的
空调方式。分层空调负荷是确定空调系统向室内提供冷量的主要依据，也是评估
分层空调节能量的关键。区别于常规空调负荷，目前大空间建筑分层空调负荷计
算主要考虑在空调区常规空调负荷（如围护结构传热负荷、室内热源负荷、新风
或渗透负荷等）的基础上增加辐射转移负荷和对流转移负荷，这两者均是非空调
区向空调区转移热形成的负荷，是大空间建筑分层空调负荷计算的关键。本文以
两个关键问题之一的辐射转移热及其辐射转移负荷为研究重点，解决其中诸多的
科学问题。
首先，以均匀热环境同步模型为载体，分别针对壁面和空气建立热平衡方程，
其中壁面辐射分别考虑采用直接辐射模型、Gebhart 辐射模型和有效辐射模型求解。
通过三种同步模型理论计算的壁面温度和室内空气温度与实测值比较结果表明：
基于 Gebhart 辐射模型的计算结果与有效辐射模型计算结果具有相同的精度，与直
接辐射模型结果相比，在变壁面热流密度实验工况下提高 0.02～0.44℃的精度，在
变送风量实验工况下提高 0.07～0.21℃的精度；且 Gebhart 辐射模型计算量比有效
辐射模型降低一半。因此，本文选择 Gebhart 辐射模型作为非空调区对空调区的辐
射转移热计算模型。
针对典型大空间建筑物理模型，利用 Gebhart 辐射模型建立非空调区对空调区
的辐射转移热计算模型。论文提出实际计算中只需采用直接辐射模型计算非空调
区向空调区地板的辐射转移热，采用模型修正系数 C0修正直接辐射模型计算结果，
同时采用空调区得热修正系数 C1修正地板辐射转移得热，便可获得非空调区向空
调区的辐射转移热。论文研究了随建筑尺寸缩放、建筑宽长比、相对分层高度等
13 种因素对 C0和C1的影响规律。研究结论为：C0、C1主要受建筑宽长比、建筑
相对高度和相对分层高度等因素的影响，针对这些影响因素，论文研究了便于工
程设计的辐射转移热计算用模型修正系数 C0线算图（3-26）和壁面空调区得热修
正系数 C1线算图（3-27），以及太阳空调区得热修正系数线算图（3-36）。通过具
体算例，研究了分层空调逐时辐射转移热的计算方法，研究成果为分层空调辐射
转移负荷计算提供了科学依据。
针对大空间建筑自身结构和辐射转移热分布特点，论文通过 5个周期性扰量
的实验工况研究了用于计算辐射转移负荷的基于两种假设的辐射时间序列方法：
一是采用 PRF/RTF Generator 软件计算辐射环境室地板的太阳辐射时间因子，采用
基于实验的辐射得热和辐射时间因子计算辐射负荷，与实测地板辐射负荷进行对
比，对比结果吻合度较好，峰值误差最大为 2.29%，均值误差最大为 3.22%，平均
相对误差最大为 5.72%；另一是针对 5个面的假想大空间空调区域，利用实验辐射
得热和辐射负荷整理出的传递函数系数求得辐射时间因子，由此计算得到的辐射
负荷与实测的假想大空间辐射负荷进行对比，峰值误差最大为-1.82%，均值误差最
大为-1.22%，平均相对误差最大为 2.0%。研究结论表明基于地板和假想大空间空
调区的辐射时间序列计算方法都是可靠的，为采用辐射时间序列方法计算分层空
调辐射转移负荷提出了理论依据。
基于上述研究，本文提出了两种大空间分层空调辐射转移负荷计算方法：一
是基于地板假设的辐射转移负荷计算方法，由于地板太阳辐射时间因子随地板尺
寸改变时各项值最大改变 3.6%，因此可根据大空间建筑的地板类型，选择确定论
文表 4-1ASHRAE Fundamentals 2013 年中提出的太阳辐射时间因子，由此可根据
逐时辐射转移热计算逐时辐射转移负荷；另一是基于大空间分层空调区假设的辐
射转移负荷计算方法，采用分层空调区的延迟时间和衰减倍数作为选择 ASHRAE
文献中归纳的 14 种建筑结构类型（涵盖了 200640 种典型区域结构）的依据，由
对应的传递函数系数计算获得相应的辐射时间因子，再根据逐时辐射转移热计算
得到逐时辐射转移负荷。采用标准算例对上海、广州和北京三个地区的辐射转移
负荷计算结果表明，两种计算方法平均相对误差最大为 3.22%。
论文最后以下送中回的大空间实验房为研究对象，对本文提出的辐射模型、
基于地板假设的大空间建筑分层空调辐射转移热及辐射转移负荷计算方法通过 2
个实验工况进行了验证。研究结果表明：地板辐射得热量计算值相对误差均为 0.3%
左右，空调区辐射转移热平均相对误差最大为 5.29%，辐射转移负荷平均相对误差
最大为 6.77%。
本文提出的辐射转移热及辐射转移负荷计算方法，是大空间建筑分层空调负
荷计算方法的关键内容。分层空调负荷的准确计算对大空间建筑冷量计算、能耗
分析、机组容量选择具有重要理论依据和指导意义。
关键词：大空间建筑 分层空调 辐射转移热 辐射转移负荷 辐射时间
序列方法
ABSTRACT
To save energy and to improve indoor environmental quality, the stratified air
conditioning, which refers only to the lower part (the staff residence zone) and the upper
space is without air conditioning, is used widely in large space buildings. The stratified
cooling load is a foundation for determining the capacity of air conditioning system
which was applied to supply cooling air to the interior, but also the key to determine the
energy savings of stratified cooling. Presently, method for calculation of the stratified
cooling load is that adding the radiant transfer load and convection transfer load on
conventional air conditioning load for air-conditioned zone (such as the building
envelope heat load, indoor heat load, fresh air or penetration load, etc.). This thesis
focuses on the radiant heat transfer and its cooling load, which is one of the two key
issues, and to solve many scientific problems among them.
Firstly, on the basis of the principle of thermal equilibrium, heat balance equation
was established for the wall and air as a control body respectively on the uniform
environment, of which the radiant parts used the direct radiant model, Gebhart radiant
model, and effective radiant model, respectively. We calculated wall temperature and
indoor air temperature by these synchronized theoretical models, and compared with
measured values. Furthermore, these radiant models have been systematically studied.
Results show that: calculated results in the Gebhart radiant model had the same
precision on the effective radiant model, but it improved the accuracy of 0.02 ~ 0.44℃
than the direct radiant model in changing wall heating values condition, and increased
0.07 ~ 0.21 ℃ in changing room ventilation rates condition. Moreover, the workload of
the Gebhart radiant model was halved lower than effective radiant model. Therefore, the
Gebhart radiant model was chosen to calculate the radiant transfer cooling load which
was formed by non-air-conditioned area to air-conditioned area.
Secondly, the computational model of the radiant heat transfer between the
non-air-conditioned area and air-conditioned area was established for the physical
model of typical large space building. The direct radiant model was adopted to calculate
the radiant transfer heat which was formed by non-air-conditioned area to the floor of
air-conditioned area. Simultaneously, the radiant transfer heat could be directly
calculated by using the model correction coefficient C0 and air-conditioned heat
correction coefficient C1. We studied that the effect of 13 factors, for example, building
size scaling, building width and length ratio and the relative stratified height, on the C0
and C1 for the calculation of radiant heat transfer. We found that the C0 and C1 are
mainly affected by the building size scaling, building ratio height and relative stratified
height. In response to these factors, to make the calculation of the radiant transfer heat
in engineering design convenient, we provided the line operators of the model
correction coefficient C0 (Figure 3-26), line operators of the air-conditioned heat
correction coefficient C1 (Figure 3-27) and line operators of the solar air-conditioned
heat correction coefficient C1 (Figure 3-36) in this thesis. Additionally, the hourly
radiant heat transfer of stratified air conditioning has been studied for specific examples,
and its conclusion provided reference for calculation of the radiant transfer load to
stratified air conditioning system.
Thirdly, with regard to the distribution of radiant heat transfer in large space
building, we studied the radiant time series methods (based on two hypotheses), which
were used to calculate the radiant transfer load. On the one hand, the PRF / RTF
Generator software was adopted to compute the solar radiant times factors of
environment room floor. The radiant load was calculated and compared with the load of
measured floor, and the maximum error for their peak was 2.29%, the maximum error
for mean value was 3.22 %, and the maximum average relative error was 5.72% in a
cycle. On the other hand, according to the partial air-conditioned area of large imaginary
space, we obtained the transfer function by using 24 radiant heat and load, and get the
24 radiant times factors through matrix operations. In addition, the radiant load was
obtained and further compared with the load of measured air-conditioned area. Results
shown that the maximum error of peak load is -1.82%, the maximum average error is at
most -1.22 % and the maximum relative error is 2.0% in a cycle. Results also shown
that it was reliable for the calculation based on the floor and air-conditioned area in a
hypothetical large space, and lay a solid theoretical foundation for the introduction of
radiant time series methods to calculate the radiant transfer load of stratified air
conditioning.
In summary, this thesis proposed two methods to calculate the radiant transfer load.
The first one was that all radiant heat was assumed distribute on the floor of
air-conditioned area. Because the solar radiant time factors was changed little with floor
size, the solar radiant time factors proposed by ASHRAE Fundamentals 2013 could be
selected according to the floor type of the large-space buildings. The second one was
that the hourly radiant transfer load can be calculated. The radiant heat was uniformly
distributed in the walls of air-conditioned area. It was chosen the 14 typical
constructions (covers 200640 typical constructions) of ASHARE literature, based on the
delay and attenuation coefficients of air-conditioned area, and the radiant time factor
could be calculated by matrix operation, and hourly radiant transfer load could also be
calculated. According to standard examples, the radiant transfer loads of three areas
(Shanghai, Guangzhou, and Beijing) were concluded and we found that the mean
maximum relative error of two calculation methods was 3.22%.
Finally, based on the experimental large room, it was validated by experiments for
the method about randiant model, radiant transfer heat and radiant transfer load of
stratified air conditioning proposed by this thesis. Results indicate that the radiant error
of floor was about 0.3% and the error of air-conditioned area was less than 5.29%, but it
was 6.77% for the maximum error of radiant transfer load.
In this thesis, we established the method for calculation of radiant heat transfer and
radiant transfer load. This method is important for load calculation of stratified air
conditioning, and has important theoretical and reference values for calculation of
cooling capacity, analysis of energy-consumption, and selection of unit capacity in the
large space building.
Key Words: Large space building, Stratified air conditioning, Radiant
transfer heat, Radiant transfer load, Radiant time series
method
目 录
中文摘要
ABSTRACT
第一章 绪 论 .................................................................................................................. 1
1.1 论文研究背景及意义 ............................................................................................ 1
1.2 大空间建筑分层空调负荷研究现状及辐射转移负荷计算存在问题 ................ 3
1.2.1 大空间建筑分层空调负荷研究历程与国内传统计算方法 ........................ 3
1.2.2 大空间建筑分层空调辐射转移负荷计算存在的问题 ................................ 5
1.3 空调区辐射得热与辐射负荷计算方法研究 ........................................................ 6
1.3.1 围护结构得热常规处理方法 ........................................................................ 6
1.3.2 建筑内壁面辐射换热计算方法研究 ............................................................ 8
1.3.3 空调区辐射负荷计算方法研究 .................................................................... 9
1.4 本文研究内容与研究路线 .................................................................................. 12
第二章 建筑内壁面辐射模型对比研究 ...................................................................... 16
2.1 引言 ...................................................................................................................... 16
2.2 建筑内壁面对流辐射耦合换热分析与同步模型的建立 .................................. 16
2.2.1 热环境同步模型构建思路 .......................................................................... 16
2.2.2 基于直接辐射模型的壁面热平衡方程 ...................................................... 18
2.2.3 基于 Gebhart 辐射模型的壁面热平衡方程 ............................................... 19
2.2.4 基于有效辐射模型的壁面热平衡方程 ...................................................... 20
2.2.5 热环境同步模型及求解方法 ...................................................................... 22
2.3 建筑内壁面辐射模型对比实验方案 .................................................................. 24
2.3.1 实验室空调系统及其实验条件 .................................................................. 24
2.3.2 实验方案与实验仪器 .................................................................................. 27
2.3.3 预实验与实验工况的确定 .......................................................................... 30
2.4 建筑内壁面辐射模型对比实验研究 .................................................................. 34
2.4.1 变壁面热流密度时不同辐射模型计算结果与实验结果的对比分析 ...... 34
2.4.2 变送风量时不同辐射模型计算结果与实验结果的对比分析 .................. 37
2.5 建筑内壁面辐射特性及其换热量对比研究 ...................................................... 41
2.5.1 变壁面发射率时不同辐射模型壁温计算结果与分析 .............................. 41
2.5.2 基于不同辐射模型时的辐射换热量特性对比分析 .................................. 45
2.6 本章结论 .............................................................................................................. 47
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：177 页
大小：7.09MB
格式：PDF
时间：2025-01-09
