管壳式换热器模型原程序(C语言)

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换热器模型原程序(C语言)#include<math.h>#include<stdio.h>float density(float t,float d){float x,z;x=1+(t/100);z=0.942+0.248*x+0.174*d*d+0.0841/(x*d)-0.312*x/d-0.556*exp(-x); z=z*1000;return(z);}/*以下为比热容的计算:*/float hcap(float t,float d){float cp;cp=(0.7072+(0.00147-0.000551*d)*t-0.318*d)*(0.055*12.5+0.35); cp=cp*4186;return(cp);}/*以下为热导率的计算:*/float hcon(float t,float d){float cn;cn=0.1008*(1-0.00054*t)/d;cn=cn*4186/3600;return(cn);}float nianc(float t,float d){float ni;ni=exp(exp(22.81142-3.68738*log(t+273)))-1.22;ni=ni*density(t,d)*0.000001;return(ni);}float nianh(float t,float d){float ni;ni=exp(exp(18.9173-2.92782*log(t+273)))-1.22;ni=ni*density(t,d)*0.000001;return(ni);}main(){ int n,N;float tc1,tc2,th1,th2,k,q,e,h,hi,ho,ntu,rei,reo,pri,pro,wc,tao,wh,tmc,tmh,ai,ao,twi,two,cpc,cph,rdc,rdh,ndc,ndh,di,dou,dk,d1,d2,s1,s2,cmin,cmax,de,p,l,v1,v2,rs,rt,thx,tx,ty,thy,tcx,tcy;tc1=160; th1=280; wh=29.5; N=324; wc=37.5; di=0.021; dou=0.025; dk=0.8; l=6.0; p=0.032; n=0; rs=0.0005; rt=0.0001;thx=th1;do{tmh=(th1+thx)/2;cph=hcap(tmh,0.919);q=wh*cph*(th1-thx);tcx=tc1;do{tmc=(tc1+tcx)/2;tc2=tc1+q/(wc*hcap(tmc,0.850));tcy=tcx;tcx=tc2;}while(fabs(tc2-tcy)>0.1);tmc=(tc1+tc2)/2;d1=density(tmc,0.850);d2=density(tmh,0.919);cpc=hcap(tmc,0.850);rdc=hcon(tmc,0.850);rdh=hcon(tmh,0.919);ndc=nianc(tmc,0.850);ndh=nianh(tmh,0.919);s1=3.1415926*0.25*di*di*N*0.5;v1=wc/d1/s1;ai=3.1415926*di*N*l;rei=di*v1*d1/ndc;pri=cpc*ndc/rdc;s2=0.230*dk*(1-dou/p);v2=wh/d2/s2;de=4*(p*p-3.1415926*0.25*dou*dou)/(3.1415926*dou);reo=de*v2*d2/ndh;pro=cph*ndh/rdh;ao=3.1415926*dou*N*l;h=0.023*pow(rei,0.8)*pow(pri,0.33)*rdc/di;hi=h;twi=tmc+q/(h*ai);do{hi=h*pow(ndc/nianc(twi,0.850),0.14);tx=twi;twi=tmc+q/(hi*ai);}while(fabs(twi-tx)>0.5);hi=h*pow(ndc/nianc(twi,0.850),0.14);if(reo>2000)h=0.36*pow(reo,0.55)*pow(pro,0.33)*rdh/de;if(reo<=2000)h=0.527*pow(reo,0.5)*pow(pro,0.33)*rdh/de;ho=h;two=tmh-q/(h*ao);do{ho=h*pow(ndh/nianh(two,0.919),0.14);ty=two;two=tmh-q/(ho*ao);}while(fabs(two-ty)>0.5);ho=h*pow(ndh/nianh(two,0.919),0.14);k=1/((1/hi+rt)*ao/ai+1/ho+rs);cmin=wh*cph;cmax=wc*cpc;ntu=k*ao/(wh*cph);tao=ntu*sqrt(1+(cmin/cmax)*(cmin/cmax));e=2/(1+(cmin/cmax)+sqrt(1+(cmin/cmax))*(1+exp(-tao))/(1-exp(-tao)));th2=th1-e*(th1-tc1);tc2=tc1+(cmin/cmax)*(th1-th2);thy=thx;thx=th2;n++;printf("output of the recycle %d:\n",n);printf("Rei=%f,",rei);printf("Reo=%f,",reo);printf("Pri=%f,",pri);printf("Pro=%f\n",pro);printf("Hi=%f,",hi);printf("Ho=%f,",ho);printf("Th2=%f,",th2);printf("Tc2=%f\n",tc2);printf("e=%f\n",e);printf("NTU=%f\n",ntu);printf("K=%f\n",k);}while(fabs(th2-thy)>0.1);}现采用一管壳式换热器,以蒸馏塔釜排出的渣油预热原油。

已知换热器结构为双管程单壳程,壳内径为0.8m ,管束规格为Φ25×2mm ,长度为6.0m ,共324根,材质为碳钢。

管束的管子按正方形排列,管心距为32mm 。

壳程设有切除25%的折流板,间距为230mm ,原油走管程,渣油走壳程。

已知冷物流的条件有: 渣油:流量W h =106200㎏/h ,温度T h1=280℃; 原油:流量W c =135000㎏/h ,温度T c1=160℃;污垢热阻:渣油侧:R s =0.0005m 2℃/W ;原油侧:R t =0.0001 m 2℃/W ; 相对密度:=+++---22020200.08410.3120.9420.2480.174()0.556exp()XD X D X XD D式中 =+1/100m X T , T m -----定性温度, D 20-----20℃时油品相对密度,可查取或实测; 对渣油,K 渣油=12.5,对原油,K 原油=12.5 定压热容:=+-⋅-⋅⋅+2020[0.7072(0.00147)0.000551)0.318](0.0550.35)p c D t D K 热导率: λ=-⋅200.1008[10.00054]/t D Kcal/( m ·℃·h )粘度: ν=+⋅+-exp{exp[ln(273)]} 1.22a b t 厘泊 ν=+-⋅+11ln[ln( 1.22)]ln(273)a b t νν⎛⎫++= ⎪++⎝⎭1122ln( 1.22)273ln[]/ln ln( 1.22)273t b tν1------温度为t 1时的运动粘度,厘泊;ν2------温度为t 2时的运动粘度,厘泊。

如选t 1=50℃,t 2=100℃,可查得ν1渣油=1500,ν2渣油=120,ν1原油=90, ν2原油=13将已知条件各数值赋予程序中相应的变量,运行后可得如下结果:即:output of the recycle 1:Rei=5459.146973,Reo=7749.009277,Pri=52.925968,Pro=70.550148 Hi=499.244751,Ho=805.451111,Th2=245.832932,Tc2=190.821411 e=0.284726NTU=0.409956K=235.563385output of the recycle 2:Rei=7134.744629,Reo=6253.752930,Pri=41.856537,Pro=84.399651 Hi=617.473083,Ho=729.976990,Th2=243.293076,Tc2=191.539963 e=0.305891NTU=0.455251K=255.301697output of the recycle 3:Rei=7265.567383,Reo=6151.324219,Pri=41.198006,Pro=85.579514 Hi=625.540039,Ho=723.879333,Th2=243.161789,Tc2=191.541321 e=0.306985NTU=0.457643K=256.173096output of the recycle 4:Rei=7272.351562,Reo=6146.061035,Pri=41.164467,Pro=85.641144 Hi=625.955139,Ho=723.561829,Th2=243.155197,Tc2=191.541229 e=0.307040NTU=0.457763K=256.216125所以最终结果为:原油出口温度:191.54℃渣油出口温度:243.16℃传热效率: 0.307总传热系数: 256.22W/(m2·℃)原油雷诺数:7272.35渣油雷诺数:6146.06管程流体表面传热系数:625.96壳程流体表面传热系数:723.56。