主动式冷梁诱导性能研究与优化设计

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摘要

主动式冷梁是一种带新风诱导的气—水换热末端设备。由空调机组处理的室

外新风（一次风）被送入冷梁内，经过喷嘴的高速射流在冷梁内部形成局部负压，

从而诱导室内空气（二次风）从回风面板进入冷梁内，与盘管进行热交换，冷却

或加热后的二次风与一次风混合，最终经送风通道进入室内。主动式冷梁系统由

于其显著的节能效益、良好的气流组织分布、舒适的室内空气品质以及低噪音等

优点，已被定位新世纪的绿色空调系统，采用主动式冷梁的建筑有助于

LEED

评

鉴加分以及绿色节能标志的申请。

诱导比

作为衡量主动式冷梁诱导性能的重要指标，其定义为二次风与一次

风的比值，它的大小决定了室内设计温度和送风量是否能够满足空调系统的设计

要求。在相同条件下，诱导比大的主动式冷梁所需一次风量少，空调机组能耗少，

同时，一次风风管尺寸减小，降低了空调系统的投资。由于主动式冷梁的结构形

式对诱导性能有较大影响，因此，合理设计主动式冷梁的结构形式提高主动式冷

梁的诱导比，对提高室内舒适性、降低能源消耗、减少系统投资至关重要。本文

主要分析了相关结构参数对主动式冷梁诱导性能的影响，并对主动式冷梁进行了

优化设计。主要研究内容包括以下几个方面：

（1）主动式冷梁诱导性能的理论研究：根据气体射流相关理论基础，主要研

究了主动式冷梁的射流结构形式，分析了主动式冷梁射流的轴线流速衰减规律和

流量沿轴线的变化规律，对主动式冷梁诱导性能进行了理论推导与分析，得出主

动式冷梁的诱导性能主要与喷嘴直径、喷嘴间距、喷嘴至送风通道两侧的水平距

离以及送风通道的长度等结构参数相关。根据简化的气体射流理论计算公式，对

所研究的主动式冷梁多股平行受限射流下的诱导比进行了理论计算，得出不同喷

嘴直径下的诱导比范围，为进一步研究主动式冷梁诱导性能的正确性及合理性提

供了理论依据。

（2）主动式冷梁诱导性能的数值研究：利用

FLUENT

软件对主动式冷梁进

行三维建模，并用理论结果与实验结果验证了模型的正确性，在此基础上，研究

分析了射流倾角、喷嘴直径、喷嘴入口角、喷嘴间距和回风面板开孔率单个因素

变化时，主动式冷梁诱导性能的变化规律。结果表明：随着射流倾角的增加，主

动式冷梁诱导比先增加后减小，一次风量变化时，诱导比均在射流倾角为 20°时

取得最大值。随着喷嘴直径的增加，主动式冷梁诱导比逐渐减小，而且喷嘴直径

越大，一次风量的变化对诱导比的影响越不显著，喷嘴直径为 4mm、5mm、6mm、

7mm 和8mm 时，诱导比的变化范围分别是：2.95~3.48、2.56~2.64、2.13~2.20、

1.85~1.86 和1.62~1.65。随着喷嘴入口角的增加，主动式冷梁诱导比逐渐减小，喷

嘴入口角从 0°增加至 20°时，喷嘴直径为 4mm 的诱导比从 3.28 减至 2.86。随着

喷嘴间距的增加，主动式冷梁诱导比先增加后减小，喷嘴间距在 36mm~72mm 之

间变化时，主动式冷梁诱导比最大，而且一次风量越大，喷嘴间距越小，诱导性

能越好，反之亦然。随着回风面板开孔率的增加，主动式冷梁诱导比逐渐增加，

而且一次风量越小，诱导比受开孔率变化的影响程度越显著。

（3）主动式冷梁诱导性能的优化研究：根据上述研究结果，选取射流倾角、

喷嘴间距、喷嘴入口角和回风面板开孔率 4个因素，采用正交设计法，共建立 9

种数学模型，计算不同工况下主动式冷梁诱导比和送风速度，通过直观分析法和

方差分析法，探索 4种因素综合变化时，对诱导比和送风速度两种评价指标的影

响程度和最佳设计参数，从而对主动式冷梁的诱导性能进行了优化设计。结果表

明：喷嘴射流倾角为 20°，喷嘴间距为 36mm，喷嘴入口角为 0°，回风面板开孔

率为 42%时，主动式冷梁诱导性能最好，喷嘴直径 4mm、5mm 和6mm 的诱导比

分别达到：3.52、2.78 和2.30。

关键词：主动式冷梁射流理论诱导性能数值模拟正交设计法

ABSTRACT

Active chilled beam is a gas-water heat terminal equipment with fresh air induction.

the outdoor air (primary air) handled by the conditioning unit is sent into the inside of

chilled beam, the inside of chilled beam forms a partial vacuum through the nozzle high

speed jet , thereby inducing the indoor air (secondary air) into the chilled beam from the

panel, after the heat exchange with the coil, the secondary air mixing with the primary

air is sent into the room from the outlet of chilled beam. due to its remarkable energy

efficiency, good airflow distribution, comfortable air quality and low noise etc, active

chilled beam system has been defined a green air-conditioning system, it can help

LEED accreditation points and apply green logo of building energy.

Induction ration is a important indicator to measure the performance of active

chilled beam, which is defined the ratio of secondary air and primary air, it determines

the indoor temperature and air volume to meet the design requirements of air

conditioning system. Under the same conditions, the induction ratio is larger, the

primary air required active chilled beam is less, the energy consumption of air

conditioning unit is less, meanwhile, the tube size of primary air decreases and the

investment of air conditioning system is less. Due to the structure form of active chilled

beam has a greater impact on the performance of induction, therefore, the rational

structure is critical to improve indoor comfort, reduce energy consumption and

investment of system. The article analyzes the influence of the structural parameters to

the performance of induction, researches the law of performance of induction, and the

active chilled beam is optimized. The main work of this paper includes the following

aspects:

(1) Study on the theories of the performance of induction of active chilled beam:

According to the theoretical foundation of jet, the jet structure of active chilled beam

was researched, the attenuate law of the axis velocity and the law of the flow variation

along the way were analyzed, there were some theoretical derivation and and analysis

for the performance of induction, the performance of induction was mainly relevant

with the nozzle diameter, the spacing of nozzle, the horizontal distance of the nozzle

center form the both sides of the channel and the length of air channel. According to the

simplified theoretical formula of gas jet, the induction ratio of multiple strands parallel

limited jet was calculated for active chilled beam, the range of induction ratio was

obtained for different diameters, it provided theoretical basis to further study the

correctness and rationality of the performance of induction.

(2) Numerical study on the performance of induction for active chilled beam:The

three-dimensional model was built by FLUENT software, using the theoretical and

experimental results to verify the correctness of the model, on this basis, the law of the

performance of induction was studied, when the individual factors of jet angle, nozzle

diameter, inlet angle of nozzle, spacing of nozzle and opening rate of return air panel

changes. The results showed: With the increasing of jet angle, the induction ratio

increased firstly and decreased, when the primary air was different, the induction ratio

got the maximum value in the jet angle 20°. With the increasing of nozzle diameter, the

induction ratio gradually decreased, and the bigger of the nozzle diameter, in the range

of primary air volume, the change of induction ratio was not more significant, the

nozzle diameter was 4mm, 5mm, 6mm, 7mm and 8mm, the variation range of induction

ratio were: 2.95~3.48, 2.56~2.64, 2.13~2.20, 1.85~1.86 and 1.62~1.65. With the

increasing of inlet angle of nozzle, the induction ratio gradually decreased, when the

inlet angle of nozzle increased from 0°to 20°，the induction ratio reduced from 3.28 to

2.86 for the nozzle diameter of 4mm. With the increasing of nozzle spacing, the

induction ratio increased firstly and decreased, when the nozzle spacing changed

between in 32mm~72mm, the induction ratio was maximum, and the more of primary

air volume, the smaller of nozzle spacing, the performance of induction was better. With

the increasing of opening rate, the induction ratio gradually increased, and when

primary air was smaller, the inpact that the variation of opening rate to induction ratio

was more significant.

(3) Study on optimization of active chilled beam: According to the above research

results, the jet angle, the spacing of nozzle, the inlet angle of nozzle and the opening

rate of return air panel were selected, according to the orthogonal design, 9

mathematical models were established, the induction ratio and velocity of active chilled

beam were calculated under different conditions, through the visual analysis and

analysis of variance, the degree of influence and the best design parameters that

different factors to induction ratio and velocity were explorated. The results showed:

when the jet angle was 20°, the spacing of nozzle was 36mm, the inlet angle of nozzle

was 0°, the opening rate of return air panel was 42%, the performance of induction of

active chilled beam was best. the induction ratio of nozzle diameter 4mm, 5mm and

6mm can reach 3.52, 2.78 and 2.30.

Keywords: active chilled beam, the theory of jet, the performance of

induction, numerical simulation, orthogonal design method

中文摘要

ABSTRACT

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

1.1 研究背景 ................................................................................................................ 1

1.2 辐射空调系统分类 ................................................................................................ 2

1.3 主动式冷梁简介 .................................................................................................... 4

1.3.1 主动式冷梁空气处理过程 ............................................................................ 5

1.3.2 主动式冷梁的性能参数 ................................................................................ 6

1.3.3 主动式冷梁系统的特点 ................................................................................ 7

1.4 主动式冷梁研究现状 ............................................................................................ 8

1.4.1 国外研究现状 ................................................................................................ 8

1.4.2 国内研究现状 ................................................................................................ 9

1.5 课题研究意义和内容 .......................................................................................... 10

1.5.1 课题研究的意义 .......................................................................................... 10

1.5.2 课题研究的内容 ........................................................................................... 11

第二章主动式冷梁诱导性能的理论分析 .................................................................. 13

2.1 气体射流的基本理论 .......................................................................................... 13

2.1.1 射流的分类 .................................................................................................. 13

2.3.2 射流的结构 .................................................................................................. 14

2.3.3 射流微分方程 .............................................................................................. 15

2.2 有限空间射流理论 .............................................................................................. 16

2.2.1 有限空间射流结构 ...................................................................................... 16

2.2.2 有限空间射流动力特性 .............................................................................. 17

2.3 主动式冷梁射流诱导性能理论分析 .................................................................. 18

2.3.1 主动式冷梁射流结构及外边界方程 .......................................................... 19

2.3.2 主动式冷梁轴线流速衰减规律 .................................................................. 20

2.3.3 主动式冷梁流量沿程变化规律 .................................................................. 21

2.3.4 主动式冷梁诱导性能分析 .......................................................................... 23

2.3.5 主动式冷梁诱导比计算 .............................................................................. 26

2.4 本章小结 .............................................................................................................. 28

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摘要：

摘要主动式冷梁是一种带新风诱导的气—水换热末端设备。由空调机组处理的室外新风（一次风）被送入冷梁内，经过喷嘴的高速射流在冷梁内部形成局部负压，从而诱导室内空气（二次风）从回风面板进入冷梁内，与盘管进行热交换，冷却或加热后的二次风与一次风混合，最终经送风通道进入室内。主动式冷梁系统由于其显著的节能效益、良好的气流组织分布、舒适的室内空气品质以及低噪音等优点，已被定位新世纪的绿色空调系统，采用主动式冷梁的建筑有助于评鉴加分以及绿色节能标志的申请。诱导比作为衡量主动式冷梁诱导性能的重要指标，其定义为二次风与一次风的比值，它的大小决定了室内设计温度和送风量是否能够满足空调系统的设计要求。在相同条件下，...

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