空冷式换热器的最优化.pdf

第25卷増
动力工程
Vol 25 Su
2005年10月
JOLRNAL OF POWER ENGIXEERING
空冷式换热器的最优化
叶立,童正明,朱汝红2,李楠
(1.上海理工大学动力工程学院,上海200093;:2.扬州水箱有限公司,扬州225009)
摘要:建立了在两侧流体均不混合的情况下,侧流体进口温度不均匀?又流换热器性能影响
的最优设计模型,并在此基础上编制出空冷器最优设计程序。运用所编程序对进口温度不均匀的
横交叉式和单程式空冷器进行分析,得出其最住进凵温度分布形式具有一定的规律性,即最佳温
度分布应使换热器在换热初始部分尽可能保持小的温差役热,而在换热器中间部分尽可能保持人
的混差传热。计算结果表明:対于小温差范围内传热的空冷器,优化不均匀进∏温度其效果将非
常显著;在相同温度水平条件下,管内流体进∏温度不均匀的优化效果要大大高于空气进口温度
不均匀的优化效果。通过对优化模型进行实验验证,得出埋论计算与实验的有效度相对误差小于
2%,证明了理论模型的正确性,可进一步推广使用。
关键词:工程热物理;优化设计;优化程序;空冷换热器
Opt imizat ion of Air-cooled Heat Exchanger
YE Li, TONG Zheng-ming, ZHU Rul-hong, LI Nan
1. Univcrsity of Shanghai for Scicncc and Techology School of Powcr Enginccring, Shanghai, 200093
2. Yangzhou Radiator Co Ltd, Yangzhou, 225009)
Abstract: A optimized design code has been established for determining the heat trans er effectiveness o
crossflow heat exchanger with both Muis unmixed, accounting for the e ect of the ununiformity of inlet luid
temperature of one fluid side. A computation program developed on this code was used to analyse parallel
multipass and onc pass air-coolcd hcat changers, and produced the optimum inlct tcmpcraturc distribution
discipline, i.c. maintaining inlct tcmpcraturc diffcrencc at thc side-part of exchangers as small as possiblc whilc
maintaining that al the middle-part as large as possible. The computed results show the optimized electiveness is
extremely remarkable on heat exchangers those have small temperature differences in heat transfer. Under the
same temperature conditions, optimizing the ununiform inlet temperature of liguid side will achieve much better
cffccts than optimizing ununiform inlct tcmpcraturc of air sidc. Thc rclativc diffcrcncc bctwccn cfficicncy dcgrce
produced by computation program and experiments, is not more than 2%o Agreement between predicted dala and
experimental data proved the validity of our design code, as well as its potential for urther use
Key words: engineering thermophysics; optimization design optimization programme; air-cooled heat exchanger
作者简介:叶立(1977-),女,汉族,四川成都人,助教,主要从事換热
器传热性能研究及优化设计
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