论文总字数：27546字

摘 要

本文分为三个部分：首先，文章对翅片管式热交换器的定义、结构、国内外研究和发展现状进行综述。其次，本文通过理论计算设计了一台空气冷却器，以对其形成完整的全面的了解。最后，文中采用流体计算软件Icepak 对影响翅片管式换热器流动和传热性能的因素进行数值模拟分析。

在数值模拟中，本文先建立一个基本模型，通过尝试不同的算法参数、精确度参数、网格参数等设置，对具有相同边界条件的同一模型进行数值模拟，并将模拟结果处理后与手工计算结果进行对比，选取结果最接近的一组作为后续模拟计算的参照组。计算结束后，本文先以基本模型为例对其温度场、速度矢量场、速度标量场以及压力场进行定性分析以了解整个翅片管式换热器的传热状况，从图中可以直观的看出换热强烈和换热薄弱以及流动剧烈和流动平稳的区域。然后文中将后处理的Re 数、Nu 数、传热系数h、范宁摩擦系数f 、传热热阻R 等数据与变量参数（H型翅片间距S、翅片厚度δ、翅片高度d）整理成折线图的形式，以定性分析各因素的具体影响趋势。

通过模拟计算并比较数据得出结果：随着迎面风速增大，Re 数增大，Nu 数增大，摩擦系数f 减小，传热热阻R 也减小；随着翅片间距增大，Nu 数减小，摩擦系数f 减小，对传热热阻R 的影响较小；随着翅片厚度增大，Nu 数增大，摩擦系数f 明显减小，传热热阻R 也显著减小；随着翅片高度增加，Nu 数增加，摩擦系数f 也增加，而传热热阻R减小，在本文中研究的影响因素中优先考虑的因素为：翅片间距、翅片厚度及翅片高度。

关键词：H型翅片圆管 数值模拟 传热特性流动特性

Analysis on heat transfer and flow of inline H-type Finned Tube

Abstract

From the global view, the paper will be departed into three stages. Firstly, a roughly review of the definition, structure, domestic and foreign research and the current development conditions about finned tube heat exchanger was given. Secondly, in order to form a more comprehensive understanding of the heat exchanger, an air-cooler through traditional theoretical calculation methods was designed. Finally, the numerical simulation analysis was carried out about how the following five factors(fin spacing, fin thickness, fin height, imperforated or perforated, different positions of rectangular holes) impact the flow and heat transfer characteristics of finned tube heat exchanger with the fluid calculation software-Icepak.

In the part of establishing numerical model,three steps have to be accomplished. Primarily,to obtain a fiducial model, different parameter settings were tried such as algorithm parameters,precision parameters, lattice parameter. And then numerical simulation was performed on the same model with the equal boundary conditions. After that, the comparison between results of the simulation and statics calculated manually was conducted, which means that a basic model could be selected with its characteristic parameters like the heat transfer coefficient, fanning fiction factors and the heat transfer resistance being most close to the simulation results. And then, changing one of the five assumed factors (fin spacing, fin thickness, fin height,imperforated or perforated, different positions of rectangular holes) alone and collecting enough useful dates for some more analysis in detail helped to find the specific influence mechanism on the heat transfer coefficient, the fanning friction factor and the heat transfer resistance of finned tube heat exchanger.On the one hand, the software Icepak could read some distribution map like the temperature field,the velocity vector field, the speed of scalar field and the pressure field from which the reader could easily discriminate the region where the heat transfer was strong and the area with enhanced flowing. On the other hand, drafting the Re number, Nu number, heat transfer coefficient h, the fanning friction factor f and heat transfer resistance R after the post processing with variable parameters (fin spacing S, fin thicknessδ , fin height d) into line graph forms made it convenient to analyze the five specific factors' influencing trend on H-type finned tube exchanger.

At last, after the numerical simulation and comparative analysis, the following results can be achieved: with the increasing of wind speed, the Re number, and Nu number are both enhanced, while the fanning friction factor f and the thermal resistance of R decrease; with the increasing of fin spacing, the Nu number and the fanning friction factor f both experience a decreasing process, but the heat transfer resistance R remains basically unchanged; with the increasing of fin thickness, the Nu number increase which means that the heat transfer is enhanced remarkably, but on the contrary, the fanning friction factor f and the thermal resistance of R reduce significantly; With the increasing of fin height, the Nu number and the fanning friction factor f both ascend, while the heat transfer resistance R go through a decreasing process.In this paper ，fin spacing, fin thickness and fin height are the three factors would be better considered preferentially when designing the finned tube exchanger.

Keywords: H-type circular finned tube; numerical simulation; heat transfer characteristic;flow characteristic

目 录

摘要 I

Abstract II

第一章 概论 1

1.1引言 1

1.2 H型翅片管的概述 1

1.3 H型翅片管的工作原理及优势 3

1.4.国内外对H型翅片圆管的研究 4

1.5.H型翅片圆管的应用 5

1.6结语 6

第二章 翅片管模型及设计 7

2.1 翅片管物理模型及介绍 7

2.2翅片管模型建立 9

2.3物理和几何模型的建立 10

2.4典型翅片管换热器—空冷器设计计算 15

2.5小结 15

第三章 数值模型建立 20

3.1 边界条件 20

3.2网格划分 20

3.3 小结 24

第四章 数据处理及分析 25

4.1 传统理论计算方法 25

4.2 模拟结果后处理计算 28

4.3 模拟结果云图分析 30

4.4 模拟数据汇总及分析 40

4.5 小结 40

第五章 结果与展望 46

5.1 结论 46

5.2 展望 47

致谢 48

参考文献 49

第一章 概论

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