initial commit / add all books

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+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