扬 州 市 职 业 大 学
毕 业 设 计（论 文）
设计（论文）题目：
系别：专业：班级：姓名：学号：指导老师：完成时间：
工程机械热交换器
温度控制系统的优化设计与研究
机械工程学院
机械制造及自动化专业 10专接本（1）班 周天程 104610252084 高艳 2012年5月
目 录
目 录 ........................................................................................................................... 2 摘 要 ........................................................................................................................... 1 主要符号表 ................................................................................................................... 3 第一章 绪论 ................................................................................................................. 2
1.1散热器的分类 ..................................................................................................................... 2 1.2 汽车散热器概述 ................................................................................................................ 3
1.2.1 汽车散热器的原理 ................................................................................................. 3 1.2.2 汽车散热器的结构 ................................................................................................. 3 1.2.3 汽车散热器的材料及加工工艺 ............................................................................. 4 1.3 散热器存在的问题 ............................................................................................................ 5
第二章 汽车散热器结构设计 ..................................................................................... 6
2.1 散热管 ................................................................................................................................ 6 2. 2散热带 ................................................................................................................................ 6 2.3主片及上下水室 ................................................................................................................. 7 2.4散热器的固定框架 ............................................................................................................. 7 2.5散热水管 ............................................................................................................................. 8
第三章 管带式散热器传热过程的理论分析 ............................................................. 9
3.1 管带式散热器的传热计算 ................................................................................................ 9
3.1.1 散热面积的计算 ..................................................................................................... 9 3.1.2 当量直径的计算 ..................................................................................................... 9 3.1.3 对数平均温差△t m.............................................................................................. 10 3.1.4 传热系数K ........................................................................................................... 10
3.1.4.1 总传热系数K ............................................................................................ 10 3.1.4.2 气侧换热系数Ho ...................................................................................... 12 3.1.4.3 水侧换热系数hi ........................................................................................ 12
3.2 散热器阻力计算 .............................................................................................................. 13
3.2.1风侧阻力 ................................................................................................................ 13 3.2.2 水侧阻力 ............................................................................................................... 14
第四章 提高散热器散热性能的有效途径 ............................................................... 15
4.1 改善传热系数 .................................................................................................................. 15 4.2 增加对数平均温差 .......................................................................................................... 16 4.3 扩大传热面积F .............................................................................................................. 17 4.4 减少散热器重量 .............................................................................................................. 17
第五章 管带式散热器的校核和设计方案 ............................................................... 19
方案一：芯子的正面尺寸不变，通过改变芯子厚度来达到不同的散热要求。 ............. 19 方案二：芯子的外观尺寸不变，通过改变芯子中水管通流截面的结构尺寸，改变管带结构尺寸达到不同的散热要求。 ............................................................................................. 20
第六章 管带数学模型的建立 ................................................................................... 21
6.1 设计中的原始数据和设计工况 ...................................................................................... 21 6.2 优化问题的确定 .............................................................................................................. 21 6.3 数学模型的建立 .............................................................................................................. 22
6.3.1 建立目标函数 ....................................................................................................... 22 6.3.2 建立约束函数 ....................................................................................................... 23
第七章 基于MATLAB优化工具箱实现管带数学模型求解 ................................ 25
7.1 Matlab的产生与发展 ...................................................................................................... 25 7.2 MATLAB的优势与特点 ................................................................................................. 26 7.3 管带优化方法的选择 ...................................................................................................... 27 7.4 设计结果及比较分析 ...................................................................................................... 29
总结 ............................................................................................................................. 32 致谢 ............................................................................................................................. 33 参考文献 ..................................................................................................................... 34
扬州职业大学毕业论文
摘 要
随着汽车工业的飞跃发展，对发动机散热器的要求也越来越高。在保证散热器具有足够散热能力和强度的前提下，体积更小、重量更轻、管壁及带材更薄、散热效率更高成了散热器发展的必然趋势，所以实现散热器的优化设计已经具有紧迫性。
本文阐述了管带式散热器的结构，工作原理；研究了管带式散热器的传热和流动阻力特性；散热器性能强化的有效途径：改善传热系数K，增加对数平均温差△tm，扩大散热面积F，减轻散热器的的重量M；探讨管带式散热器的校核和设计方法；管带式散热器的优化设计。
本文通过对金叶水箱厂MHD284散热器结构进行优化，运用计算机编程，在MATLAB环境中建立管带式的数学模型，分析其传热及阻力特性，以实现性能的最优化。
关键词：管带式；散热器；传热分析；优化设计；MATLAB
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扬州职业大学毕业论文
Abstract
With the rapid development of automobile industry, the requirement of the engine radiator more and more is also high. In guarantee radiator cooling capacity and with sufficient strength, under the premise of smaller, lighter weight and wall and more thin strip, the cooling efficiency higher become an inevitable trend in the development of radiator, so realize the optimization design of the radiator has urgency.
This paper introduces the structure of the type radiator, principle of work, The research introduces type radiator of the heat transfer and flow resistance characteristic; The effective ways to strengthen the radiator performance: improve the heat transfer coefficient K, increase the logarithmic mean temperature difference enables delta tm, expand the cooling area F, reduce the weight of the radiator M; Discusses the type radiator both test and design methods; Both side of the optimization design of the radiator.
This article through to the gold leaf water tank factory MHD284 radiator structure optimization, using computer programming, in the MATLAB environment in which to set up the both side of mathematical model, analyzes its heat transfer and the resistance character, in order to realize the optimum performance.
Keywords: both type; The radiator; Heat transfer analysis; Optimization design; MATLAB
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