管壳式换热器模拟计算

管壳式换热器模拟计算管壳式换热器模拟计算 （课本 P40 2-5 题） 程序中各参数的意义： 字母意义字母意义 n 迭代次数 niu1/2 冷/热物料运动粘度 Ai/Ao 管内外传热面积 yita1/2 冷/热物料粘度 D 壳体直径 B 折流板间距 L 管长度 t 管心距 Di/Do/Dm 管内径/外径/平均管径 niuwi/o 内外表面壁温下运动粘度 Ko 总传热系数 yitawi/o 内外表面壁温下粘度 De 壳程当量直径 Dwi/o 内外表面壁温下相对密度 Si 管程通道截面积 rouwi/o 内外表面壁温下密度 Smax 壳程通道截面积 ld 管材（碳钢）热导率 Wh 热物料(渣油)流量 b 管壁厚 Wc 冷物料(原油)流量 Hi0/Ho0 管内外表面传热系数初值 Th1/Tc1 热/冷物料入口温度 Hi/Ho 管内外表面传热系数 Th2/Tc2 热/冷物料出口温度 Qh/Qc 热/冷物料热流量 Th20/Tc20 热/冷物料出口温度初值 Twi0/Two0 热/冷物料壁温初值 Cp1/Cp2 热/冷物料定压比热容 Twi/Two 热/冷物料壁温 C 热容流率比(热/冷) Rs/Rt 热/冷物料侧污垢热阻 Tmh/Tmc 热/冷物料定性温度 ui/uo 管/壳程流速 D1/D21 热/冷物料相对密度 Rei/Reo 管/壳程雷诺数 K 油品特性因数 Pri/Pro 管/壳程普朗特数 rou1/rou2 冷/热物料密度 NTU 传热单元数 lamada1/2 冷/热物料热导率 E 传热效率 程序条文： # include # include main() double Do=0.025，Di=0.021，L=6，Wh=29.5; Th1=280，Wc=37.5， Tc1=160，Ro=0.0005,Ri=0.0001，D1,D2，D2O1=0.85，D2O2=0.919，Tc2,Th2， MD2O1，MD2O2，K=12.5,Cp1,Cp2，ramda1,ramda2，niu1,niu2， yita1,yita2,a1,b1,a2,b2,Tc20,Th20,Tmc,Tmh,C,Qc,Qh, Ho,Hi,Reo,Rei,Pro,Pri,Si,rou1,ui,Hi0,Twi0, Ai,Twi,niuwi,yitawi,Dwi,Xwi,rouwi,Ao, Smax,B=0.23,D=0.8,t=0.032,De,uo,rou2, Ho0,Two0,Two,niuwo,yitawo,Dwo,Xwo,rouwo， Ko，NTU,E,F,Cmin,Cmax，Xh,Xc，ld=44,b=0.002,Dm=0.0023，e=2.71828; int n=0; Tc2=180; Th2=260; /*给 Tc2，Th2 赋初值*/ do n+; printf(“n=%dn“,n); Th20=Th2; Tmh=(Th1+Th20)/2; doTc20=Tc2; /*Tc2 的迭代*/ Tmc=(Tc1+Tc20)/2; Cp1=(0.7072+(0.00147-0.00051*D2O1)*Tmc- 0.318*D2O1)*(0.055*K+0.35)*4.18*1000; Cp2=(0.7072+(0.00147-0.00051*D2O2)*Tmh- 0.318*D2O2)*(0.055*K+0.35)*4.18*1000; C=Wh*Cp2/(Wc*Cp1); Tc2=Tc1+C*(Th1-Th20); while(fabs(Tc2-Tc20)=0.1); Qh=Wh*Cp2*(Th1-Th2); Qc=Wc*Cp1*(Tc2-Tc1); Ai=3.14*Di*L*324; Si=0.25*3.14*Di*Di*324/2; Xc=1+Tmc/100.0; MD2O1=pow(D2O1,2); D1=0.942+0.248*Xc+0.174*MD2O1+0.0841/(Xc*D2O1)-0.312*Xc/D2O1- 0.556*exp(-Xc); rou1=1000*D1; ui=Wc/(rou1*Si); b1=log(log(90.0+1.22)/log(13+1.22)/(log(50.0+273)/(100.0+273) ; a1=log(log(90+1.22)-b1*log(50.0+273); niu1=exp(exp(a1+b1*log(Tmc+273)-1.22; yita1=niu1*rou1/1000000; Rei=Di*ui*rou1/yita1; ramda1=0.4213*(1-0.00054*Tmc)/D2O1/3.6; Pri=Cp1*yita1/ramda1; Hi0=0.027*pow(Rei,0.8)*pow(Pri,0.33)*ramda1/Di; Twi0=Tmc+Qc/(Hi0*Ai); do /*管壁内壁温的迭代*/ niuwi=pow(e,pow(e,a1+b1*log(Twi0+273)-1.22; Xwi=1+Twi0/100.0; Dwi=0.942+0.248*Xwi+0.174*MD2O1+0.0841/(Xwi*D2O1)-0.312*Xwi/D2O1- 0.556*exp(-Xwi); rouwi=1000*Dwi; yitawi=niuwi*rouwi/1000000; Hi=Hi0*(pow(yita1/yitawi),0.14); Twi=Tmc+Qc/(Hi*Ai); Twi0=Twi; while(fabs(Twi-Twi0)=0.5); Ao=3.14*Do*L*324; Smax=B*D*(1-Do/t); De=4*(t*t-0.25*3.14*Do*Do)/(3.14*Do); Xh=1+Tmh/100.0; MD2O2=pow(D2O2,2); D2=0.942+0.248*Xh+0.174*MD2O2+0.0841/(Xh*D2O2)-0.312*Xh/D2O2- 0.556*exp(-Xh); rou2=1000*D2; uo=Wh/(rou2*Smax); b2=log(log(1500+1.22)/log(120+1.22)/(log(50.0+273)/(100.0+273) ); a2=log(log(1500+1.22)-b2*log(50.0+273); niu2=exp(exp(a2+b2*log(Tmh+273)-1.22; yita2=niu2*rou2/1000000; Reo=De*uo*rou2/yita2; ramda2=0.4213*(1-0.00054*Tmh)/D2O2/3.6; Pro=Cp2*yita2/ramda2; Ho0=0.36*pow(Reo,0.55)*pow(Pro,0.33)*ramda2/De; Two0=Tmh-Qh/(Ho0*Ao); do /*管壁外壁温的迭代*/ niuwo=exp(exp(a1+b1*log(Two0+273)-1.22; Xwo=1+Two0/100; Dwo=0.942+0.248*Xwo+0.174*MD2O1+0.0841/(Xwo*D2O1)-0.312*Xwo/D2O1- 0.556*exp(-Xwo); rouwo=1000*Dwo; yitawo=niuwo*rouwo/1000000; Ho=Ho0*(pow(yita2/yitawo),0.14); Two=Tmh-Qh/(Ho*Ao); Two0=Two; while(fabs(Two-Two0)=0.5)； Ko=1/(1/Hi+Ri)*Ao/Ai+1/Ho+Ro+b/ld*Do/Dm); /*以管外表面为基准， 计算传热系数 K*/ Cmin=Wh*Cp2; Cmax=Wc*Cp1; NTU=Ko*Ao/Cmin; /*传热单元数*/ F=NTU*sqrt(1+pow(Cmin/Cmax,2); E=2/(1+Cmin/Cmax)+sqrt(1+Cmin/Cmax)*(1+exp(-F)/(1-exp(-F); /*传热效率*/ Th2=Th1-E*(Th1-Tc1); Tc2=Tc1+C*(Th1-Th2); printf(“Th2=%.1lftTc2=%.1lfn“,Th2,Tc2); printf(“Rei=%.2lftPri=%.2lftHi=%.2lfn“,Rei,Pri,Hi); printf(