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Diffstat (limited to '1328/CH10/EX10.1/10_1.sce')
-rw-r--r-- | 1328/CH10/EX10.1/10_1.sce | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/1328/CH10/EX10.1/10_1.sce b/1328/CH10/EX10.1/10_1.sce new file mode 100644 index 000000000..0fe8afdd0 --- /dev/null +++ b/1328/CH10/EX10.1/10_1.sce @@ -0,0 +1,73 @@ +printf("\t example 10.1 \n");
+printf("\t approximate values are mentioned in the book \n");
+T1=250; // inlet hot fluid,F
+T2=250; // outlet hot fluid,F
+t1=95; // inlet cold fluid,F
+t2=145; // outlet cold fluid,F
+W=16000; // lb/hr
+w=410; // lb/hr
+printf("\t 1.for heat balance \n");
+printf("\t for crude \n");
+c=0.485; // Btu/(lb)*(F)
+Q=((W)*(c)*(t2-t1)); // Btu/hr
+printf("\t total heat required for crude is : %.2e Btu/hr \n",Q);
+printf("\t for steam \n");
+l=945.5; // Btu/(lb)
+Q=((w)*(l)); // Btu/hr
+printf("\t total heat required for steam 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);
+printf("\t On the assumption that the fluids are mixed between passes, each pass must be solved independently. Since only two passes are present in this exchanger, it is simply a matter of assuming the temperature at the end of the first pass. More than half the heat load must be transferred in the first pass; therefore assume ti at the end of the first pass is 125°F \n");
+ti=125; // F
+tc=((t1)+(ti))/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,steam \n");
+ho=(1500); // condensation of steam Btu/(hr)*(ft^2)*(F)
+printf("\t individual heat transfer coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n",ho);
+printf("\t cold fluid:inner tube side,crude \n");
+Nt=86;
+n=2; // number of passes
+L=12; //ft
+at1=0.594; // flow area, in^2,from table 10
+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/(.177)); // mass velocity,lb/(hr)*(ft^2)
+printf("\t mass velocity is : %.2e lb/(hr)*(ft^2) \n",Gt);
+mu2=2.95*2.42; // at 145F,lb/(ft)*(hr)
+D=(0.87/12); // ft
+Ret1=((D)*(Gt)/mu2); // reynolds number
+printf("\t reynolds number is : %.0f \n",Ret1);
+mu3=4.8*2.42; // at 110F,lb/(ft)*(hr)
+D=(0.87/12); // ft
+Ret2=((D)*(Gt)/mu3); // reynolds number
+printf("\t reynolds number is : %.0f \n",Ret2);
+c=0.485; // Btu/(lb)*(F),at 120F,from fig.2
+k=0.0775; // Btu/(hr)*(ft^2)*(F/ft), from table 4
+Pr=((c)*(mu3)/k); // prandelt number
+printf("\t prandelt number is : %.1f \n",Pr);
+Hi=((1.86)*(k/D)*((Ret2*(D/L)*Pr)^(1/3))); // using eq.6.1,Btu/(hr)*(ft^2)*(F)
+printf("\t Hi is : %.1f Btu/(hr)*(ft^2)*(F) \n",Hi);
+muw=1.2*2.42; // lb/(ft)*(hr),at 249F from fig.14
+phyt=(mu3/muw)^0.14;
+printf("\t phyt is : %.1f \n",phyt); // from fig.24
+hi=(Hi)*(phyt); // from eq.6.37
+printf("\t Correct hi to the surface at the OD is : %.0f Btu/(hr)*(ft^2)*(F) \n",hi);
+tp=(tc)+(((ho)/(hi+ho))*(T1-tc)); // from eq.5.31
+printf("\t tp is : %.0f F \n",tp);
+delt=tp-tc; //F
+printf("\t delt is : %.0f F \n",delt);
+Ai1=0.228 // internal surface per foot of length,ft
+Ai=(Nt*L*Ai1/2); // ft^2
+printf("\t total surface area is : %.1f ft^2 \n",Ai);
+delt3=((hi*Ai*delt)/(W*c)); // delt3=ti-t1, F
+printf("\t delt3 is : %.1f F \n",delt3);
+ti=t1+delt3; // F
+printf("\t ti is : %.1f F \n",ti);
+printf("\t The oil now enters the second pass at 126.9°F \n");
+// end
+
+
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