板式空预器性能研究与分析

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3.0 赵德峰 2024-11-11 4 4 3.69MB 75 页 15积分

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摘要

板式空预器由于其优良的换热性能和流动阻力性能，近些年来在石油、化工

等许多行业的烟气余热回收中得到大量应用。但对其流动和传热特性的实验研究，

由于工作量巨大和行业竞争而鲜见报道。本文对板式空预器进行了试验研究和数

值模拟，为其设计和应用提供理论依据。

首先针对平板板式空预器进行试验研究，得出其换热特性关联式和流阻特性

关联式。建立物理模型，利用 Fluent 进行数值模拟计算，模拟结果与实验结果进

行对比，验证了模拟数据的可靠性。

接着，在实验和模拟的基础上，通过增加扰流片，利用数值模拟计算研究其

对换热器性能的影响，发现扰流片对换热器的换热性能有所提高，但增幅不大，

但流动阻力却大大增加，使得换热器的综合性能下降很大，单纯靠增加扰流片来

提升板式换热器性能的效果不是很理想。

在此基础上，从板片本身入手，将平板变为波纹板，对波纹板式空预器板片

结构的主要参数进行数值模拟，研究了波纹倾角、波纹法向节距、波纹高度和板

间距四个因素对板片性能的影响：

a)波纹倾角对于板片的换热性能影响很大，随着波纹倾角的增大，换热性能提

高，阻力损失增加，在波纹倾角 β=45°时换热器具有较优的性能。

b)波纹高度对于板片的换热性能影响也比较大，随着波纹高度的增加，换热性

能提高，阻力损失也增加。对于基准板型，波纹高度 H=10mm 时板片性能较好。

在对压降要求比较苛刻的场合，建议设计较小波纹高度的板片。

c)板间距对于板片换热性能也有影响，在同样的流速下，随着板间距的减小，

板片换热性能增加，同时阻力损失也增加，但换热器的综合性能因子是增加的。

换热器在较小的板间下距具有较优的性能。减小板间距还可以使换热面的布置更

加的紧凑，在同一热负荷下换热器的体积更小。对于板式空预器，为防止堵灰要

求有一定宽度的通道。综合考虑实际使用场合，设计较小板间距的板式换热器。

d)波纹节距对于板片换热性能的影响较小，随着波纹节距的减小，板片换热性

能略有增加，但压力损失的增加却非常大。较大一些的波纹节距具有较好的综合

性能。对于基准板型，波纹节距 P=30mm 时板片性能较优。

最后，对板式空预器的适用性，如积灰、磨损、低温腐蚀等问题进行了讨论，

提出了解决方案，为其进一步的应用提供理论指导。

关键字：板式换热器空预器准则关系式数值模拟平板波纹板

ABSTRACT

Due to the excellent heat transfer performance and flow resistance performance of

plate air preheater, in recent years it has been widely used in the petroleum, chemical

and many other industries in the flue gas waste heat recovery. However, due to huge

workload and competition in the industry, experimental study of its flow and heat

transfer characteristics rarely reported. This paper studied and simulated plate air

preheaters, and give a design and application of its theoretical basis.

Firstly, research the flat-plate air preheater by experiment, draw its heat transfer

characteristics and flow resistance characteristics of relational. Establish the physical

model, the numerical simulation using the Fluent calculation, simulation results and

experimental results were compared to verify the simulated data reliability.

Then, on the basis of experiments and simulations, by increasing the spoiler, use

numerical simulation to study the performance of the heat exchanger, and found that

spoiler on the performance of heat exchangers has increased, but the increase was not

However, the flow resistance is greatly increased, making the overall performance of

the heat exchanger decreased greatly, simply by increasing the spoiler to improve the

performance of plate heat exchangers effect is not very satisfactory.

On this basis, so from the plate itself, change the flat plate into corrugated plate,

simulation the main parameters of corrugated plate air preheater plate structure, research

the effect of corrugated inclination, corrugated pitch , corrugation height and plate

spacing four factors on the performance of the plate, revealing its inherent laws, and

then guide the engineering design.

a) Corrugated inclination make a big difference to the performance of plate heat

exchanger, with the corrugated angle increases, the heat transfer performance improve,

resistance loss increase. The heat exchanger has excellent performance when the

corrugated angle β= 45°.

b) The height of the corrugated impact plate heat exchanger performance is large

also, with the ripple height increases, the heat exchanger improve. For reference plate

type, when the corrugation height H=10mm, the plate’s performance is better. At

pressure drop requirements demanding occasions, recommend designing smaller ripple

height plate.

c) The impact on plate spacing plate heat exchanger for impact, at the same flow

rate, with the plate spacing decreases, the plate heat transfer performance increased

while pressure loss it increased, but the performance of the heat exchanger is to increase

the factor. Heat exchanger in the smaller distance between the plates has a lower

optimum performance. Reducing the plate spacing of the heating surface can also make

a more compact arrangement, the same heat load heat exchanger smaller. For plate air

preheater, to prevent fouling requires a certain width of the channel. Considering the

actual use situation, the design of the smaller plate spacing to increase the heat

exchanger performance.

d) For the corrugated board sheet pitch of the heat transfer performance is small,

decreases as the ripple pitch, plate heat transfer performance increased slightly, but the

increase in pressure loss is very large. Some larger ripple pitch has good overall

performance. For reference plate type, corrugated pitch P = 30mm better performance

when the plates.

Finally, the applicability of air preheater plate, such as fouling, wear, temperature

corrosion and other issues were discussed, proposed solutions for its further application

to provide theoretical guidance.

Keywords: Plate heat exchanger, Air pre-exchanger, Criteria

relationship, Numerical simulation, Flat plate,

Corrugated plate

摘要

ABSTRACT

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

1.1 前言 ................................................................................................................. 1

1.2 板式换热设备简介 ......................................................................................... 1

1.2.1 板式换热器的发展 ............................................................................... 2

1.2.2 板式换热器的优缺点 ........................................................................... 2

1.2.3 板式换热器的分类 ............................................................................... 3

1.3 板式换热器的研究现状 ................................................................................. 6

1.3.1 板式换热器结构研究 ........................................................................... 7

1.3.2 板式换热器的传热和流动 ................................................................... 8

1.3.3 研究技术拓展 ....................................................................................... 8

1.3.4 换热性能评价 ....................................................................................... 9

1.4 本课题拟完成的主要任务 ............................................................................. 9

第二章数值模拟的理论基础及方法 ....................................................................... 11

2.1 数值模拟的理论基础 ................................................................................... 11

2.1.1 数值模拟研究 ..................................................................................... 11

2.1.2 湍流研究进展 ..................................................................................... 11

2.1.3 k-ε模型简介 ........................................................................................ 12

2.1.4 数值模拟的方法 ................................................................................. 13

2.2 数值模拟分析介绍 ....................................................................................... 14

2.2.1 模拟结构 ............................................................................................. 14

2.2.2 控制方程 ............................................................................................. 14

2.2.3 网格的划分 ......................................................................................... 17

2.2.4 边界条件及设置 ................................................................................. 18

2.2.5 计算过程 ............................................................................................. 19

2.3 本章小结 ....................................................................................................... 19

第三章平板板式空预器的性能研究 ....................................................................... 21

3.1 平板板式空预器介绍 ................................................................................... 21

3.2 实验研究 ....................................................................................................... 21

3.2.1 实验介绍 ............................................................................................. 21

3.2.2 实验原理 ............................................................................................. 23

3.2.2 实验结果分析 ..................................................................................... 27

3.3 数值模拟 ....................................................................................................... 29

3.3.1 几何结构 ............................................................................................. 29

3.3.2 传热特性分析 ..................................................................................... 30

3.3.3 阻力特性分析 ..................................................................................... 32

3.4 扰流片影响因素分析 ................................................................................... 33

3.4.1 扰流片对速度分布的影响 ................................................................. 34

3.4.2 扰流片对温度分布的影响 ................................................................. 34

3.4.3 扰流片对压力分布的影响 ................................................................. 36

3.4.4 扰流片对换热器综合性能的影响 ..................................................... 37

3.5 本章小结 ....................................................................................................... 38

第四章波纹板式空预器模拟分析 ........................................................................... 39

4.1 数值模拟 ....................................................................................................... 39

4.1.1 模拟结构 ............................................................................................. 39

4.1.2 边界条件和设置 ................................................................................. 39

4.1.3 模拟参数 ............................................................................................. 40

4.2 波纹板式空预器流动和换热性能分析 ....................................................... 41

4.2.1 波纹倾角的研究 ................................................................................. 42

4.2.2 波纹高度的研究 ................................................................................. 46

4.2.3 波纹节距的研究 ................................................................................. 50

4.2.4 板间距的研究 ..................................................................................... 54

4.3 本章小结 ....................................................................................................... 59

第五章板式空预器的适用性分析 ........................................................................... 60

5.1 采用模块化单体设计 ................................................................................... 60

5.2 防止露点腐蚀 ............................................................................................... 61

5.3 防止堵灰和磨损 ........................................................................................... 62

5.4 本章小结 ....................................................................................................... 63

第六章总结和展望 ................................................................................................. 64

6.1 总结 ............................................................................................................... 64

6.2 展望 ............................................................................................................... 64

符号表 ......................................................................................................................... 66

参考文献 ..................................................................................................................... 67

在读期间公开发表论文和承担科研项目及取得成果 ............................................. 70

致谢 ............................................................................................................................. 71

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摘要：

摘要板式空预器由于其优良的换热性能和流动阻力性能，近些年来在石油、化工等许多行业的烟气余热回收中得到大量应用。但对其流动和传热特性的实验研究，由于工作量巨大和行业竞争而鲜见报道。本文对板式空预器进行了试验研究和数值模拟，为其设计和应用提供理论依据。首先针对平板板式空预器进行试验研究，得出其换热特性关联式和流阻特性关联式。建立物理模型，利用Fluent进行数值模拟计算，模拟结果与实验结果进行对比，验证了模拟数据的可靠性。接着，在实验和模拟的基础上，通过增加扰流片，利用数值模拟计算研究其对换热器性能的影响，发现扰流片对换热器的换热性能有所提高，但增幅不大，但流动阻力却大大增加，使得换热器的综合性能...

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