管壳式换热器设计计算用matlab源代码

%物性参数%有机液体取69度p1=997;cp1=2220;mu1=0.0006;num1=0.16;%水取30度p2=995.7;mu2=0.0008;cp2=4174;num2=0.62;%操作参数%有机物qm1=18;%-----------有机物流量--------------dt1=78;dt2=60;%水t1=23;t2=37;%----------自选-----------%系标准选择dd=0.4;%内径ntc=15;%中心排管数dn=2;%管程数n=164;%管数dd0=0.002;%管粗d0=0.019;%管外径l=0.025;%管心距dl=3;%换热管长度s=0.0145;%管程流通面积da=28.4;%换热面积fie=0.98;%温差修正系数----------根据R和P查表------------B=0.4;%挡板间距-----------------自选--------------%预选计算dq=qm1*cp1*(dt1-dt2);dtm=((dt1-t2)-(dt2-t1))/(log((dt1-t2)/(dt2-t1)));R=(dt1-dt2)/(t2-t1);P=(t2-t1)/(dt1-t1);%管程流速qm2=dq/cp2/(t2-t1);ui=qm2/(s*p2);%管程给热系数计算rei=(d0-2*dd0)*ui*p2/mu2;pri=cp2*mu2/num2;ai=0.023*(num2/(d0-2*dd0))*rei^0.8*pri^0.4;%管壳给热系数计算%采用正三角形排列Apie=B*dd*(1-d0/l);%最大截流面积u0=qm1/p1/Apie;de=4*(sqrt(3)/2*l^2-pi/4*d0^2)/(pi*d0);%当量直径re0=de*u0*p1/mu1;pr0=cp1*mu1/num1;ifre0=2000a0=0.36*re0^0.55*pr0^(1/3)*0.95*num1/de;elsea0=0.5*re0^0.507*pr0^(1/3)*0.95*num1/de;end%K计算K=1/(1/ai*d0/(d0-2*dd0)+1/a0+2.6*10^(-5)+3.4*10^-5+dd0/45.4);%AAj=dq/(K*dtm*fie);disp('K=')disp(K);disp('A/A计=');disp(da/Aj);%计算管程压降ed=0.00001/(d0-2*dd0);num=0.008;err=100;fori=0:5000err=1/sqrt(num)-1.74+2*log(2*ed+18.7/(rei*sqrt(num)))/log(10);berr=err/(1/sqrt(num));ifberr0.01break;elsenum=num+num*0.01;i=0;endendft=1.5;dpt=(num*dl/(d0-2*dd0)+3)*ft*dn*p2*ui^2/2;%计算管壳压降f0=5*re0^(-0.228);F=0.5;fs=1.15;nb=dl/B-1;dps=(F*f0*ntc*(nb+1)+nb*(3.5-2*B/dd))*fs*p1*u0^2/2;disp('dpt=');disp(dpt/10^6);disp('dps=');disp(dps/10^6);disp('u0=')disp(u0);disp('ui=')disp(ui);function[numda,berr]=NumdaJS(num0,re,ed)%num0为初设摩擦系数值，re为雷诺数，ed为相对粗糙度numda=num0;berr=100;%相对误差，初始为100while(berr0.001)%当相对误差小于0.1%停止计算numda=numda+0.000001;%修改摩擦系数值err=1/sqrt(numda)-1.74+2*log(2*ed+18.7/(re*sqrt(numda)))/log(10);%计算误差berr=err/(1/sqrt(numda));%计算相对误差end