管壳式换热器设计

1目录一、前言1、选题背景·····················································12、设计要求·····················································13、基础数据·····················································1二、热交换器工艺计算1、丙二烯物性参数···············································12、水的物性参数·················································23、计算过程3.1热交换器总换热量··········································23.2热量衡算··················································33.3平均温差··················································33.4对流换热系数··············································43.5传热管规格················································43.6管内流速··················································43.7管子长度··················································43.8布管图····················································43.9管内对流换热系数··········································53.10管外对流换热系数·········································63.11接管处速度计算···········································7三、校核计算1、壁温核算······················································82、管程和壳程压降计算············································8四、工艺计算结果表···················································10五、参考文献·························································112一、前言1、选题背景：几乎在所有的工业领域都离不开换热器的使用，在石油及化工行业换热器占据投资的2540%。了解并掌握换热器的设计对以能源转换和利用为目的的热能与动力工程专业学生非常重要。2、设计要求：依据GB151-98对热交换器进行工艺计算，掌握热交换器的工艺设计过程。要求：1、选择换热管的规格，管子的布置方式，折流板的形式和间距，壳体的内径，管程和壳程的压降，接管的大小。2、做出换热器工艺计算结果的结构图。3、作出布管图。4、按照工艺计算的过程，写出详细的换热器工艺计算说明书。3、基础数据：表2-1设计基础数据壳程丙二烯流量（kgs）管程水进口温度（C）管程水出口温度（C）壳程丙二烯进口温度（C）壳程丙二烯出口温度（C）2525407040二、热交换器工艺计算1、丙二烯的物性参数丙二烯进口温度：'1t=70C丙二烯出口温度：''1t=40C丙二烯定性温度：'''11170405522mtttC丙二烯物性参数有参考文献5查得：表2-2丙二烯物性参数温度（C）密度（3gcm）热容（C卡克分子）粘度（厘泊）导热系数（-510cmsC卡）500.546025.8420.10728.3600.527626.6830.096226.555C时丙二烯的物性参数为：3310.5460+0.5276g==0.5368536.82kgcmm125.84226.68326.26252pcC卡克分子2.745kjkgC-41a0.1070.09620.1016=1.01610ps2厘泊3551(28.326.5)1027.4102cmsC卡0.1147wmC1411312.7451.01610102.4310.1147prcP2、水的物性参数冷却水进口温度：'225tC冷却水出口温度：''240tC水的定性温度：'''222254032.522mtttC有参考文献6查饱和水物性参数得：表2-3水的物性参数温度（C）密度（3kgm）热容（kjkgC）粘度（610aPs）导热系数（210wmC）30995.74.174801.561.840992.64.174653.363.532.5C时水的物性参数为：232.530995.7(995.7992.6)99540303kgm24.174pckjkgC64232.530801.5(801.5653.3)107.645104030aPs2232.53061.8(63.561.8)100.6224030wmC2422324.1747.64510105.130.622prcP3、计算过程（1）求换热器总换热量Q:111252.745(7040)2058.75pQmctkw。4（2）热量衡算计算管程水的质量流量：查取参考文献1选取热损失系数：0.98'2058.750.982017.6QQW'222pQmct'2222017.632.24.174(4025)pQkgmsct。（3）对数平均温差：按逆流形式计算：maxminmaxmin70404025()21.647040lnln4025mctftttttC'''22''124025170253ttPtt'''11'''22704024025ttRtt差参考文献1查图1-10(a)，得温差修正系数：0.885则0.8819.04mmctfttC。（4）假设总对流换热系数1K:由参考文献1可知：1400820K初步选定总传热系数1480K2wmC则'1mQKAt321'2017.610220.7648019.04mQAmKt。（5）确定传热管规格：根据参考文献1，2p表1-1选定管子直径：选用碳钢无缝光管252.5，则内径252.5220idmm。（6）假设管内流速：根据参考文献1，3p表1-3，得20.53mvs初选管内流速21.2mvs由22224idmvn，得：222224432.285.889951.23.140.02imnvd根圆整到86根。（7）由换热面积确定管子长度1L:由01AndL得10220.7632.7863.140.025ALmnd取管程数4Z,则132.78.184LLmZ根据参考文献4，21p圆整到标准值9Lm（8）确定布管图，壳体直径由参考文献4，25p,表13确定：6浮头式换热器壳体内经iD，限定圆122LiDDbbbb——当管子按正方形排列时，1.19tbn'b——管束中心线上最外层管中心至壳体内壁的距离，一般取0'11.5bd21.5nbb'1.22530bmm1.191.1986422.07tbn查参考文献4，24p表12，换热管中心距32smm，分程隔板两侧相邻管中心距44nsmm由参考文献3，式2-9粗估壳体内经12'sDbsb22.07132230735.2isDDmm圆整到800mm。1000,iD取4bmm700,iD取1510.5nbmmbmm21.512nbbmm则80025124758LDmm（9）计算管内对流换热系数ih：0.80.40.023uerNRP7222429951.20.02312367.64510ievdR0.80.40.023312365.13174.4uN2iiuhdN2174.40.6225423.840.02uiiNhd2wmC（10）计算管外对流传热系数0h：折流板间距s800l0.26733sD取l0.27sm折流板数91330.27BsLNl块查参考文献3，56p,式2.17壳体面积：00LcssLnDdAlDDsds20.7580.0250.270.80.7580.0320.0250.1920.04525cAm壳体侧流体流速：111250.243536.80.192cmmvsA壳体当量直径：2222000.025440.032440.02120.032edsdd1141536.80.2430.0212272181.01610eevdR查参考文献1，26p：0.550.5391115250.3500.4731010heeZZjRR式中Z为弓形折流板缺圆高度百分数，国际系列25Z。0.550.539251525250.350272180.47327218112.531010hj8科恩传热因子0.1413112.53hurwjNP01euhdN1w0.1411313112.53151.282.431hurwjNP10151.280.1147818.480.0212ueNhd水垢热阻241.710imCRW丙二烯污垢热阻2401.710mCRW00020111iiiiddRRKhdhd4432110.02510.0251.7101.7101.804105423.840.02964.130.02K21554K211.11.1541.2KK符合设计要求（11）接管处速度计算①管程：223300tv1.821tmvs22224tDmv2224432.2150.463.141.821995tmDmmv取圆整200mm。222224432.21.033.140.2995tmmvsD②壳程：212200sv2.02smvs921114sDmv11144251713.142.02536.8smDmmv取圆整200mm。1221144251.483.140.2536.8smmvsD三、校核计算（1）壁温核算①
管侧壁温：2211t32.5480(0.00017)19.0435.85423.84wmimitKRtCh②
壳侧壁温：110011t55480(0.00017)19.0442.3818.48wmmtKRtCh（2）管程和壳程压降计算①
管程阻力计算：tiriNiPPPFP根据参考文献1，表1-15查得1.20iF管内流动压降2242iiiiLvPfd42427.64510