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diff --git a/1328/CH12/EX12.5/12_5.sce b/1328/CH12/EX12.5/12_5.sce
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+printf("\t example 12.5 \n");
+printf("\t approximate values are mentioned in the book \n");
+T1=130; // inlet hot fluid,F
+T2=125; // outlet hot fluid,F
+T3=100; // after subcooling
+t1=80; // inlet cold fluid,F
+t3=100; // outlet cold fluid,F
+W=21000; // lb/hr
+w=167000; // lb/hr
+printf("\t 1.for heat balance \n");
+printf("\t for pentane \n");
+c=0.57; // Btu/(lb)(F)
+qs=((W)*(c)*(T2-T3)); // Btu/hr
+printf("\t total heat required for subcooling of pentane is : %.0e Btu/hr \n",qs);
+HT1=315; // enthalpy at T1, Btu/lb
+HT2=170; // enthalpy at T2, Btu/lb
+qc=(W*(HT1-HT2)); // for condensation
+printf("\t total heat required for condensing of pentane is : %.2e Btu/hr \n",qc);
+Q=qs+qc;
+printf("\t total heat required for  pentane is : %.2e Btu/hr \n",Q);
+printf("\t for water \n");
+c=1; // Btu/(lb)*(F)
+Q=((w)*(c)*(t3-t1)); // Btu/hr
+printf("\t total heat required for water is : %.2e Btu/hr \n",Q);
+deltw=18.2;
+printf("\t deltw is : %.1f F \n",deltw);
+t2=t3-deltw;
+printf("\t t2 is : %.1f F \n",t2)
+printf("\t for condensing \n");
+delt1=T2-t2; //F
+delt2=T1-t3; // F
+printf("\t delt1 is : %.0f F \n",delt1);
+printf("\t delt2 is : %.0f F \n",delt2);
+LMTDc=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));
+printf("\t LMTD is :%.1f F \n",LMTDc);
+w1=(qc/LMTDc);
+printf("\t w1 is : %.2e lb/hr \n",w1);
+printf("\t subcooling \n");
+delt3=T3-t1; //F
+delt4=T2-t2; // F
+printf("\t delt1 is : %.0f F \n",delt3);
+printf("\t delt2 is : %.0f F \n",delt4);
+LMTDs=((delt4-delt3)/((2.3)*(log10(delt4/delt3))));
+printf("\t LMTD is :%.1f F \n",LMTDs);
+w2=(qs/LMTDs);
+printf("\t w1 is : %.2e lb/hr \n",w2);
+delt=(Q/(w1+w2));
+printf("\t delt is : % .1f F \n",delt);
+Tc=((T1)+(T2))/(2); // caloric temperature of hot fluid,F
+printf("\t caloric temperature of hot fluid is : %.1f F \n",Tc);
+tc=((t1)+(t3))/(2); // caloric temperature of cold fluid,F
+printf("\t caloric temperature of cold fluid is : %.0f F \n",tc);
+printf("\t hot fluid:shell side,pentane \n");
+C1=0.198; // for 0.3Ds
+Ds=25; // in
+L=16; // ft
+N=370
+a=(C1*Ds^2);
+printf("\t a is : %.0f in^2 \n",a);
+N1=((N*a*4)/(3.14*Ds^2));
+printf("\t number of submerged tubes are : %.0f \n",N1);
+Nt=N-N1;
+printf("\t number of tubes for condensation are : %.0f \n",Nt);
+Af=(N1/N);
+printf("\t flooded surface : %.2f \n",Af);
+printf("\t for condensaton \n");
+G1=(W/(L*Nt^(2/3))); // from eq.12.43
+printf("\t G1 is : %.1f lb/(hr)*(lin ft) \n",G1);
+printf("\t cold fluid:inner tube side,water \n");
+n=4; // number of passes
+L=16; //ft
+at1=0.302; // flow area, in^2
+at=((Nt*at1)/(144*n)); // total area,ft^2,from eq.7.48
+printf("\t flow area is : %.3f ft^2 \n",at);
+Gt=(w/(at)); // mass velocity,lb/(hr)*(ft^2)
+printf("\t mass velocity is : %.1e lb/(hr)*(ft^2) \n",Gt);
+V=(Gt/(3600*62.5));
+printf("\t V is : %.2f fps \n",V);
+mu2=1.98; // lb/(ft)*(hr)
+D=0.0517; // ft
+Ret=((D)*(Gt)/mu2); // reynolds number
+printf("\t reynolds number is : %.2e \n",Ret);
+hi=940; //Btu/(hr)*(ft^2)*(F)
+printf("\t hi is : %.0f Btu/(hr)*(ft^2)*(F) \n",hi);
+ID=0.62; // ft
+OD=0.75; //ft
+hio=((hi)*(ID/OD)); // using eq.6.5
+printf("\t Correct hio to the surface at the OD is : %.0f Btu/(hr)*(ft^2)*(F) \n",hio);
+ho=251; // Btu/(hr)*(ft^2)*(F), from fig 12.9
+printf("\t Correct ho to the surface at the OD is : %.0f Btu/(hr)*(ft^2)*(F) \n",ho);
+Uc=((hio)*(ho)/(hio+ho)); // clean overall coefficient,Btu/(hr)*(ft^2)*(F)
+printf("\t clean overall coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n",Uc);
+Ac=(qc/(Uc*LMTDc));
+printf("\t clean surface required for dcondensation : %.0f ft^2 \n",Ac);
+printf("\t subcooling \n");
+ho=50; // Btu/(hr)*(ft^2)*(F)
+printf("\t individual heat transfer coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n",ho);
+Us=((hio)*(ho)/(hio+ho)); // clean overall coefficient,Btu/(hr)*(ft^2)*(F)
+printf("\t clean overall coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n",Us);
+As=(qs/(Us*LMTDs));
+printf("\t clean surface required for desuperheating : %.0f ft^2 \n",As);
+AC=As+Ac;
+printf("\t total clean surface : %.0f ft^2 \n",AC);
+UC=((Us*As)+(Uc*Ac))/(AC);
+printf("\t weighted clean overall coefficient : %.0f Btu/(hr)*(ft^2)*(F) \n",UC);
+A=1160; // ft^2
+printf("\t total surface area is : %.0f ft^2 \n",A);
+UD=((Q)/((A)*(delt)));
+printf("\t actual design overall coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n",UD);
+Rd=((UC-UD)/((UD)*(UC))); // (hr)*(ft^2)*(F)/Btu
+printf("\t actual Rd is : %.4f (hr)*(ft^2)*(F)/Btu \n",Rd);
+printf("\t pressure drop  for annulus \n");
+printf("\t condensation \n");
+printf("\t It will be necessary to spread the batHes to a spacing of 18in.to compensate for the reduction in crossfiow area due to the flooded subcooling zone. The tube-side pressure drop will be the same as before. Assume bundle flooded to 0.3Ds.\n");
+As=0.547; // ft^2
+Gs=(W/(As)); // mass velocity,lb/(hr)*(ft^2)
+printf("\t mass velocity is : %.1e lb/(hr)*(ft^2) \n",Gs);
+De=0.0792; // fig 28
+Res=((De)*(Gs)/0.0165); // reynolds number
+printf("\t reynolds number is : %.2e \n",Res);
+f=0.00121; // friction factor for reynolds number 193000, using fig.29
+s=0.00454; // for reynolds number 193000,using fig.6
+Ds=2.08; // ft
+B=18
+phys=1;
+N=(12*L/B); // number of crosses,using eq.7.43
+printf("\t number of crosses are : %.0f \n",N);
+delPsc=((f*(Gs^2)*(Ds)*(N))/(5.22*(10^10)*(De)*(s)*(phys)))/(2); // using eq.12.47,psi
+printf("\t delPsc is : %.1f psi \n",delPsc);
+printf("\t delPss is negligible \n");
+printf("\t allowable delPa is 2 psi \n");
+//end