zhengfaqi.rar_zhengfaqi_蒸发器_蒸发器计算_蒸发器设计

#include<iostream.h> #include<math.h> #define pi 3.1415926 double t1=14, t2=9, phi=91.67, d0=10*1e-3, di=8*1e-3, delta=1e-3, delta_t0=5, delta_t=3, h1=410, h4=245.92, t0=4; double rou1=1000, cp1=4.187, rou2=24.814, niu2=0.488*1e-6, a=2.41*1e-2, lamda=380, rd1=0.045*1e-3, niu1=1.255*1e-6, Pr1=9.19, lamda1=0.538; void main() { double delta_h, Mr, V1; delta_h=h1-h4; cout<<" 干壳管式蒸发器的计算结果参数如下："<<endl; cout<<"干壳管式蒸发器的循环单位质量制冷量delta_h="<<delta_h<<endl; Mr=phi/delta_h; cout<<"干壳管式蒸发器的循环制冷剂质量流量Mr="<<Mr<<endl; V1=phi/(rou1*cp1*(t1-t2)); cout<<"干壳管式蒸发器的循环冷水的体积流量V1="<<V1<<endl; double m=16*1e-3, Di=308*1e-3, N=4, Z=277, Zm=69,l=2300*1e-3, Nb=19, s1=130*1e-3, s2=85*1e-3, delta_B=32*1e-3, delta_b=5*1e-3, H1=64*1e-3, Kb1=0.1187, Kb2=0.1054, H2=59*1e-3, nb1=37, nb2=33, nc=19; double A1, A1e; A1=pi*d0*N*Zm*(l-2*delta_B); cout<<"干壳管式蒸发器的循环蒸发器外侧总面积A1="<<A1<<endl; A1e=pi*d0*N*Zm*(l-2*delta_B-Nb*delta_b); cout<<"干壳管式蒸发器干壳管式蒸发器的循环有效传热面积A1e="<<A1e<<endl; double s, Fc, uc, Fb1, Fb2, Fb, ub, u1, t1_, Re1, alpha1; s=(2*s1+18*s2)/(Nb+1); cout<<"干壳管式蒸发器折流板平均间距s="<<s<<endl; Fc=(Di-nc*d0)*s; cout<<"干壳管式蒸发器横向流通面积Fc="<<Fc<<endl; uc=V1/Fc; cout<<"干壳管式蒸发器横向流速uc="<<uc<<endl; Fb1=Kb1*Di*Di-nb1*pi*d0*d0/4; cout<<"干壳管式蒸发器折流板上缺口面积Fb1="<<Fb1<<endl; Fb2=Kb2*Di*Di-nb2*pi*d0*d0/4; cout<<"干壳管式蒸发器折流板下缺口面积Fb2="<<Fb2<<endl; Fb=(Fb1+Fb2)/2; cout<<"干壳管式蒸发器上、下缺口面积平均值Fb="<<Fb<<endl; ub=V1/Fb; cout<<"干壳管式蒸发器纵向流速ub="<<ub<<endl; u1=sqrt(ub*uc); cout<<"干壳管式蒸发器横向截面流速与折流板缺口纵向流速几何平均值u1="<<u1<<endl; t1_=(t1+t2)/2; cout<<"干壳管式蒸发器冷水的平均温度t1_="<<t1_<<endl; Re1=u1*d0/niu1; cout<<"干壳管式蒸发器在定性温度t1_下的雷诺数Re1="<<Re1<<endl; alpha1=0.22*pow(Re1, 0.6)*pow(Pr1, 0.33)*lamda1/d0; cout<<"干壳管式蒸发器管外冷水侧表面传热系数alpha1="<<alpha1<<endl; double mr, w2, alpha2, qi, q0, u2, Re2, f, delta_pr2, epsilon_R=0.75, delta_p1, delta_pi, t01, delta_t, K1, qi_star; mr=Mr/Zm; cout<<"干壳管式蒸发器每根管中的R22的质量流量mr="<<mr<<endl; w2=mr/(pi*di*di/4); cout<<"干壳管式蒸发器质量流速w2="<<w2<<endl; u2=4*Mr/(rou2*Zm*pi*di*di); cout<<"干壳管式蒸发器制冷剂饱和蒸汽流速u2="<<u2<<endl; Re2=u2*di/niu2; cout<<"干壳管式蒸发器饱和蒸汽雷诺数Re2="<<Re2<<endl; f=0.3164*pow(Re2, -0.25); cout<<"干壳管式蒸发器摩擦阻力系数f="<<f<<endl; delta_pr2=f*N*(l/di)*u2*u2*rou2/2; cout<<"干壳管式蒸发器制冷剂饱和蒸汽沿程阻力delta_pr2="<<delta_pr2<<endl; cout<<"u2*rou2="<<u2*rou2<<endl; cout<<"通过查图可以得到,epsilon_R=0.75"; cin>>epsilon_R; delta_p1=epsilon_R*delta_pr2; delta_pi=5*delta_p1; cout<<"总阻力delta_pi="<<delta_pi<<endl; t01=t0+5.6*delta_pi/100000; cout<<"蒸发器制冷剂进口温度t01="<<t01<<endl; delta_t=((t1-t01)-(t2-t0))/log((t1-t01)/(t2-t0)); cout<<"对数平均温差delta_t="<<delta_t<<endl; cout<<"预设内侧表面计算的热流密度qi="; cin>>qi; qi_star=qi; do { qi=qi_star; alpha2=57.8*a*pow(qi, 0.6)*pow(w2, 0.2)/pow(di, 0.2); K1=1/((1/alpha2)*(d0/di)+(delta/lamda)*(d0*2/(d0+di))+(1/alpha1+rd1)); qi_star=(d0/di)*(K1*delta_t); }while(fabs(qi-qi_star)>1e-1); cout<<"计算求得内侧表面计算的热流密度qi="<<qi<<endl; q0=qi*(di/d0); cout<<"外表面计算的热流密度q0="<<q0<<endl; cout<<"传热系数K1="<<K1<<endl; double A1_cal, A1_req; A1_cal=phi*1000/q0; cout<<"根据q0得所需面积的计算值A1_cal="<<A1_cal<<endl; A1_req=1.3*A1_cal; cout<<"实际所需传热面积A1_req="<<A1_req<<endl; double x; x=100*fabs((A1e-A1_req)/A1e); cout<<"x="<<x<<endl; if(fabs(x)>=5) cout<<"计算和实际面积差距超过误差5%时,重新计算!"<<endl; else cout<<"初步规划是符合要求的"<<endl; }