基于多股热羽流作用下的大空间水平射流运动模型研究

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摘要

传统的射流轨迹计算公式是在理论分析和实验基础上得出的半经验公式，没

有考虑室内热羽流对射流轨迹的影响，而目前在高大空间建筑中，由室内人员及

设备形成的热羽流广泛存在，势必对室内气流组织的设计产生重大影响。对室内

热羽流的运动特性进行研究，分析其对空调水平射流的影响规律，对高大空间建

筑室内气流组织设计以及热舒适性方面的研究都有重要的理论和现实意义。因此，

本文对多股热羽流作用下的大空间水平射流进行理论建模和模型实验分析，具有

实用价值。

论文首先对热羽流运动机理进行梳理及分析，梳理了目前比较常用的点源羽

流运动控制方程的建立及求解方法，并延伸到实体热源，针对圆板热源和受迫羽

流，介绍了虚拟点源修正法；在总结多股羽流相互作用理论基础上，建立了两股

等羽流和两股不等羽流混合成单股轴对称羽流的速度叠加修正系数，讨论修正系

数的影响因子。

论文建立了多股热羽流作用下的大空间水平射流运动机理模型。提出了单股

羽流与单股射流相遇时间与相遇面，得出了相遇时间与热源热量成正比，相遇面

高度与热源热量无关，只与射流喷口与热源间距有关的结论；建立了羽流与射流

相互作用参数β，并对其进行讨论分析；建立了单股羽流、两股等羽流以及两股不

等羽流作用下的射流无因次轨迹方程，并以实际算例对方程进行分析。两股等羽

流对射流轨迹的影响与同热量的单股羽流对射流轨迹的影响效果基本相同；两股

不等羽流对射流轨迹的影响介入两单股羽流之间，且热源热量较大者占主导地位。

论文利用模型实验，验证理论模型的正确性和可靠性。以上海国际体操中心

为原型，取几何比例尺

0.1

c

，搭建模型实验台，进行了 25 个工况实验。模型实

验结果表明，实验结果与理论分析吻合良好；通过对射流轨迹模型影响因素进行

分析后发现，羽状流的浮升力对射流轨迹的作用随着羽流间距的增大而减少，增

大羽流间距可以适当减少羽状流对射流运动的干扰；羽流放置位置靠近射流初始

段可以适当的减少羽流对射流运动的干扰；增大射流的送风高度，可减少射流轨

迹受羽状流的干扰作用；增大射流的送风速度，射流的刚性增强，对羽状流浮升

力的对抗性增大，相对的对射流的干扰作用也就减弱。

本文利用理论分析和模型实验分析了大空间内两种不同流动特性的气流间相

互掺混、相互干扰的运动过程，发现多股热羽流对射流轨迹具有一定的干扰作用，

并提出增大羽流热源间距，减小射流喷口与羽流热源之间的距离，增大送风高度

和速度等措施，减少羽状流对射流运动的干扰作用，对高大空间气流组织设计具

有一定的参考价值。

关键词：多股热羽流射流轨迹方程相互作用机理模型模型实

验

ABSTRACT

Traditional jet trajectory formula is semi-empirical formula，which on the basis of the

theoretical analysis and experiments, did not consider the indoor thermal plume，while

room personnel and equipment formed thermal plume wide spread in the large space

building now, it is bound to have a significant impact on the design of the indoor air.

Researching and analyzing of indoor turbulent plume is theoretical and practical

significance of indoor air design and thermal comfort in large space building. Therefore,

it is practicality to analyze of theoretical modeling and model experiments with the

space level jet shares of plumes.

Comb and analyze the mechanism of thermal plume movement and the establishment

of the point source plume motion control equation and solving methods, and extends to

the real heat sources, introduce the virtual origin correction for the circular plate and

forced plume; Summarize the multiple plumes interaction theory, establish of two equal

plumes and two unequal plumes merging a single axisymmetric plume velocity

correction, discuss the impact factor of the correction.

While establish the large space level jet movement mechanism model of the multiple

plumes, propose a single plume and single jet of meet time and meet face and get the

time is proportional to the heat source, the meet face height is inversely proportional to

the heat source heat conclusions; Put forward and discuss the coalescing parameter β.

Single plume, two equal plumes and two unequal plumes dimensionless trajectory

equation and analysis to a practical example of the equation. Two equal plumes of the

trajectory jet with the same heat of single plume; two unequal plumes of the trajectory

jet is between the two single plume and the greater heat source is dominant.

Thesis as the prototype of the Shanghai International Gymnastic Center, the

geometrical scale

0.1

c

, to build a model laboratory bench and do 25 conditions

experiments. Model experimental results show that the experimental results and the

theoretical analysis are in good agreement. With analyzing of impact factors on the

plume buoyancy, the heat source spacing increases can reduce the plume interfere of the

jet trajectory; plume the rigid enhanced placement near from the jet nozzle can reduce

interference plume of jet movement; increase the height of the jet blast may reduce jet

trajectory plume interference; increase the speed of jet blast may reduce jet trajectory

plume interference, because the plume buoyancy confrontational increases, relative jet

interference will weaken.

In this paper, the theoretical analysis and experimental model analysis of the two

different flow characteristics of the large space airflow blended with each other, mutual

interference during exercise. The theoretical analysis and modeling experimental studies

demonstrated a multi-strand thermal plume obvious interference jet trajectory and

proposed increases plume heat source spacing near from the jet nozzle, increasing the

blast height and speed measures to reduce the plume on jet movement interference

effect on tall space air distribution design has certain reference value.

Key Word: multiple plumes, the jet trajectory equation, interaction,

mechanism model, model experiments

摘要

ABSTRACT

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

1.1 课题来源及意义 ............................................................................................. 1

1.2 国内外研究现状 ............................................................................................. 2

1.2.1 空调非等温射流研究现状 ................................................................... 2

1.2.2 单股热羽流运动机理研究现状 ........................................................... 2

1.2.3 多股羽流混合研究现状 ....................................................................... 3

1.2.4 多相羽流的研究现状 ........................................................................... 4

1.3 论文的主要研究内容 ..................................................................................... 5

第二章热羽流运动机理梳理及分析 ......................................................................... 7

2.1 点热源形成的热羽流运动机理梳理及分析 ................................................. 7

2.1.1 点源浮力羽流运动控制方程的详析 ................................................... 7

2.1.2 点源浮力羽流运动控制方程的求解及算例详析 ............................... 9

2.2 面热源形成的浮力羽流运动机理梳理及分析 ........................................... 14

2.2.1 圆板热源分析 ..................................................................................... 15

2.2.2 虚拟点源修正 ..................................................................................... 16

2.3 受迫羽流运动机理梳理及分析 ................................................................... 17

2.4 多股羽流相互作用理论基础分析 ............................................................... 20

2.4.1 浮力羽流混合高度模型 ..................................................................... 20

2.4.2 混合羽流的运动控制方程 ................................................................. 22

2.5 建立多股羽流速度叠加修正系数 ............................................................... 24

2.5.1 两股等羽流情形 ................................................................................. 24

2.5.2 两股不等羽流情形 ............................................................................. 25

2.5.3 算例详析 ............................................................................................. 26

2.6 本章小结 ....................................................................................................... 28

第三章大空间空调水平非等温射流在多股热羽流作用下的运动机理模型 ....... 29

3.1 热羽流与空调射流相互作用现象分析 ....................................................... 29

3.2 大空间空调水平非等温射流应用概况 ....................................................... 29

3.3 水平非等温射流与热羽流相遇运动理论分析 ........................................... 31

3.3.1 水平非等温射流受力分析 ................................................................. 31

3.3.2 热羽流受力分析 ................................................................................. 34

3.3.3 单股热羽流与单股冷射流相遇时间与相遇面 ................................. 35

3.4 冷射流与热羽流相互作用模型 ................................................................... 36

3.4.1 模型的建立思路 ................................................................................. 36

3.4.2 冷射流与热羽流相互作用参数 ......................................................... 39

3.4.3 建立单股羽流作用下射流无因次轨迹方程 ..................................... 42

3.4.4 建立两股等羽流作用下射流无因次轨迹方程 ................................. 45

3.4.5 建立两股不等羽流作用下射流无因次轨迹方程 ............................. 46

3.4.6 射流轨迹特性简析 ............................................................................. 46

3.5 本章小结 ....................................................................................................... 49

第四章大空间多股热羽流作用下的空调水平射流运动模型实验研究 ............... 50

4.1 模型实验设计思路 ....................................................................................... 50

4.2 模型实验设计 ............................................................................................... 51

4.3 模型实验方案 ............................................................................................... 55

4.3.1 实验工况 ............................................................................................. 55

4.3.2 实验测点布置 ..................................................................................... 55

4.3.3 实验仪器 ............................................................................................. 58

4.3.4 实验装置设计及加工 ......................................................................... 61

4.3.5 实验前准备工作 ................................................................................. 62

4.3.6 实验流程 ............................................................................................. 63

4.4 射流轨迹实验结果分析 ............................................................................... 64

4.4.1 单股羽流作用下射流轨迹实验结果分析 ......................................... 65

4.4.2 单股羽流与单股射流相互作用参数实验结果分析 ......................... 68

4.4.3 两股等羽流作用下射流轨迹实验结果分析 ..................................... 69

4.4.4 两股不等羽流对射流轨迹的影响实验结果分析 ............................. 71

4.5 冷射流与热羽流相互作用影响因素分析 ................................................... 74

4.5.1 羽流间距 ............................................................................................. 74

4.5.2 羽流放置位置 ..................................................................................... 75

4.5.3 射流送风高度 ..................................................................................... 76

4.5.4 射流送风速度 ..................................................................................... 77

4.6 实验不确定度分析 ....................................................................................... 78

4.7 本章小结 ....................................................................................................... 80

第五章结论及展望 ................................................................................................... 82

5.1 结论 ............................................................................................................... 82

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