1 files changed, 120 insertions, 0 deletions
diff --git a/1328/CH15/EX15.4/15_4.sce b/1328/CH15/EX15.4/15_4.sce
new file mode 100644
index 000000000..9b4bde2be
--- /dev/null
+++ b/1328/CH15/EX15.4/15_4.sce
@@ -0,0 +1,120 @@
+printf("\t example 15.4\n");
+printf("\t approximate values are mentioned in the book \n");
+t1=315; // inlet cold fluid,F
+t2=335; // outlet cold fluid,F
+T1=525;
+T2=400;
+Wv=29000; // lb/hr
+Ws=38500; // lb/hr
+w=51000; // lb/hr
+printf("\t 1.for heat balance \n");
+Ht1=238; // enthalpy at t1, Btu/lb, fig 9
+Ht2=252; // enthalpy at t2, Btu/lb, fig 9
+Ht3=378; // enthalpy of vapour at t2 
+qv=(Wv*(Ht3-Ht2)); // for preheat
+printf("\t qv is : %.2e Btu/hr \n",qv);
+qs=Ws*(Ht2-Ht1);
+printf("\t qs is : %.2e Btu/hr \n",qs);
+Q=qs+qv;
+printf("\t total heat required for naphtha is : %.2e Btu/hr \n",Q);
+c=0.66; // Btu/(lb)(F)
+Q=((w)*(c)*(T1-T2)); // Btu/hr
+printf("\t total heat required for gasoil is : %.2e Btu/hr \n",Q);
+delt1=T2-t1; //F
+delt2=T1-t2; // F
+printf("\t delt1 is : %.0f F \n",delt1);
+printf("\t delt2 is : %.0f F \n",delt2);
+LMTD=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));
+printf("\t LMTD is :%.0f F \n",LMTD);
+R=((T1-T2)/(t2-t1));
+printf("\t R is : %.2f \n",R);
+S=((t2-t1)/(T1-t1));
+printf("\t S is : %.3f \n",S);
+printf("\t FT is 0.97 \n"); // from fig 18
+delt=(0.97*LMTD); // F
+printf("\t delt is : %.0f F \n",delt);
+X=((delt1)/(delt2)); // fig 17
+printf("\t ratio of two local temperature difference is : %.3f \n",X);
+Fc=0.41; // from fig.17
+Kc=0.42;
+Tc=((T2)+((Fc)*(T1-T2))); // caloric temperature of hot fluid,F
+printf("\t caloric temperature of hot fluid is : %.0f F \n",Tc);
+tc=((t1)+((Fc)*(t2-t1))); // caloric temperature of cold fluid,F
+printf("\t caloric temperature of cold fluid is : %.0f F \n",tc);
+printf("\t hot fluid:inner tube side,steam \n");
+Nt=116;
+n=8; // number of passes
+L=12; //ft
+at1=0.546; // flow area,table 10, 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 : %.2e lb/(hr)*(ft^2) \n",Gt);
+mu1=1.09; // at 451F, fig 14,lb/(ft)*(hr)
+D=0.0695; // ft
+Ret=((D)*(Gt)/mu1); // reynolds number
+printf("\t reynolds number is : %.2e \n",Ret);
+jH=168; // from fig.24
+Z=0.142; // Z=k*((c)*(mu1)/k)^(1/3), fig 16
+Hi=((jH)*(1/D)*(Z)); //, Hi=(hi/phyt)using eq.6.15d,Btu/(hr)*(ft^2)*(F)
+printf("\t individual heat transfer coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n",Hi);
+Hio=((Hi)*(0.834/1)); //Hio=(hio/phyp), using eq.6.9
+printf("\t Correct Hio to the surface at the OD is : %.0f Btu/(hr)*(ft^2)*(F) \n",Hio);
+printf("\t cold fluid:shell side,naphtha \n");
+ho1=200; // assumption
+tw=(tc)+(((Hio)/(Hio+ho1))*(Tc-tc)); // from eq.5.31, calculation mistake
+printf("\t tw is : %.0f F \n",tw);
+deltw=(tw-tc);
+printf("\t deltw : %.0f F \n",deltw);
+// from fig 15.11, hv>300, hs=60
+Av=(qv/300);
+As=qs/60;
+printf("\t qv/hv : %.3e \n",Av);
+printf("\t qs/hs : %.0e \n",As);
+A1=As+Av;
+printf("\t A : %.3e \n",A1);
+ho=(Q/A1);
+printf("\t ho : %.0f \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);
+A2=0.2618; // actual surface supplied for each tube,ft^2,from table 10
+A=(Nt*L*A2); // 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);
+// check for max. flux=Q/A=11500.(satisfactory)
+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 inner pipe \n");
+f=0.000168; // friction factor for reynolds number 59200, using fig.26
+s=0.73;
+phyt=1;
+delPt=((f*(Gt^2)*(L)*(n))/(5.22*(10^10)*(D)*(s)*(phyt))); // using eq.7.45,psi
+printf("\t delPt is : %.1f psi \n",delPt);
+X1=0.11; // X1=((V^2)/(2*g)), for Gt 1060000,using fig.27
+delPr=((4*n*X1)/(s)); // using eq.7.46,psi
+printf("\t delPr is : %.1f psi \n",delPr);
+delPT=delPt+delPr; // using eq.7.47,psi
+printf("\t delPT is : %.1f psi \n",delPT);
+printf("\t allowable delPa is negligible \n");
+printf("\t pressure drop  for annulus \n");
+Af=(3.14*(21.25^2-(116))/8);
+printf("\t flow area : %.0f in^2 \n",Af);
+as=0.917; // ft^2
+p=(3.14*21.25/2)+(3.14*1*116/2)+(21.25);
+printf("\t wetted perimeter : %.1f in \n",p);
+De=0.186; // ft
+Gs=(Ws/(2*as)); // mass velocity,lb/(hr)*(ft^2)
+printf("\t mass velocity is : %.1e lb/(hr)*(ft^2) \n",Gs);
+mu2=0.435; // at 315F, fig 14,lb/(ft)*(hr)
+Res=((De)*(Gs)/mu2); // reynolds number
+printf("\t reynolds number is : %.2e \n",Ret);
+f=0.00028; // using fig.26
+row=0.337; // fig 13.14
+// soutlet max=0.071,
+s=0.35; // using fig.6
+phys=1;
+delPs=((f*(Gs^2)*(L))/(5.22*(10^10)*(De)*(s)*(phys))); // using eq.7.44,psi
+printf("\t delPs is : %.4f psi \n",delPs);
+printf("\t allowable delPa is .25 psi \n");
+//end