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diff --git a/Process_Heat_Transfer_by_D_Q_Kern/16-Extended_Surfaces.ipynb b/Process_Heat_Transfer_by_D_Q_Kern/16-Extended_Surfaces.ipynb new file mode 100644 index 0000000..901691d --- /dev/null +++ b/Process_Heat_Transfer_by_D_Q_Kern/16-Extended_Surfaces.ipynb @@ -0,0 +1,549 @@ +{ +"cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Chapter 16: Extended Surfaces" + ] + }, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 16.1: Calculation_of_the_Fin_Efficiency_and_a_Weighted_Efficiency_Curve.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"printf('\t example 16.1 \n');\n", +"printf('\t approximate values are mentioned in the book \n');\n", +"Af=(20*0.75*12*2)/(144);\n", +"Ao=((3.14*1.25)-(20*0.035))*(12/144);\n", +"printf('\t fin surface is : %.1f ft^2/lin ft \n',Af);\n", +"printf('\t bare tube surface is : %.3f ft^2/lin ft \n',Ao);\n", +"A=(Af+Ao);\n", +"printf('\t total outside surface : %.2f ft^2/lin ft \n',A);\n", +"Ai=(3.14*1.06*12)/(144);\n", +"printf('\t total inside surface : %.3f ft^2/lin ft \n',Ai);\n", +"printf('\t fin efficiencies \n');\n", +"b=0.0625; // ft\n", +"hf=4; // from table in solution\n", +"m=(5.24*(hf^(1/2))); // m=((hf*P)/(Kax))^(1/2), eq 16.8\n", +"n=(tanh(m*b))/(m*b); // efficiency , eq 16.26\n", +"printf('\n hf m n \n '+string(hf)+' '+string(m)+' '+string(n)+' \n');\n", +"// similarly efficiencies values are calculated at different hf values\n", +"printf('\t weighted efficiency curve \n');\n", +"hfi=((n*Af)+(Ao))*(hf/Ai); // eq 16.34\n", +"printf('\n hf hfi \n '+string(hf)+' '+string(hfi)+' \n');\n", +"// similarly efficiencies values are calculated at different hf values\n", +"hf=[4 16 36 100 400 625 900]; // from 2nd table in the solution\n", +"hfi=[35.4 110.8 193.5 370 935 1295 1700]; // from 2nd table in the solution\n", +"plot2d('oll',hf,hfi);\n", +"xtitle('weighted fin efficiency curve','heat transfer coefficient to fin,Btu/(ft^2)*(hr)','coefficient hf referred to the tube ID');\n", +"//end" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 16.2: Calculation_of_a_Heat_transfer_Curve_from_Experimental_Data.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"printf('\t example 16.2 \n');\n", +"printf('\t approximate values are mentioned in the book \n');\n", +"Ts=302; // F\n", +"t1=151;\n", +"t2=185;\n", +"w=15200; // lb/hr\n", +"// The dropwise condensation of steam was promoted with oil.\n", +"aa=(3.14*(3.068^2-1.25^2))/(4*144)-((20*0.035*0.75)/(144));\n", +"printf('\t annulus flow area : %.4f ft^2 \n',aa);\n", +"p=(3.14*(1.25/12))-(20*0.035/12)+(20*0.75*2/12);\n", +"printf('\t wetted perimeter : %.2f ft \n',p);\n", +"De=(4*aa/p);\n", +"printf('\t equivalent diameter : %.3f ft \n',De);\n", +"Q=w*0.523*(t2-t1);\n", +"printf('\t heat load : %.2e Btu/hr \n',Q);\n", +"delt1=Ts-t1; //F\n", +"delt2=Ts-t2; // F\n", +"printf('\t delt1 is : %.0f F \n',delt1);\n", +"printf('\t delt2 is : %.0f F \n',delt2);\n", +"LMTD=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));\n", +"printf('\t LMTD is :%.0f F \n',LMTD);\n", +"Ai=0.277; // ft^2/ft\n", +"n=20; // number of fins\n", +"Ui=(Q/(Ai*n*LMTD));\n", +"printf('\t Ui : %.0f Btu/(hr)*(ft^2)*(F) \n',Ui);\n", +"hi=3000; // assumed value for dropwise condensation of steam\n", +"hfi=(Ui*hi)/(hi-Ui);\n", +"printf('\t hfi : %.0f Btu/(hr)*(ft^2)*(F) \n',hfi);\n", +"hf=120; // from fig 16.7 for hfi=418\n", +"mu=1.94; // lb/(ft*hr)\n", +"k=0.079;\n", +"Z=2.34; // Z=((c*mu)/k)^(1/3)\n", +"jf=(hf*De/(Z*k)); // eq 16.36\n", +"printf('\t jf : %.0f \n',jf);\n", +"Ga=(w/aa);\n", +"printf('\t Ga : %.2e lb/(hr)*(ft^2) \n',Ga);\n", +"Rea=(De*Ga/mu);\n", +"printf('\t Rea : %.2e \n',Rea);\n", +"// end\n", +"\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 16.3: Calculation_of_a_Double_Pipe_Extended_surface_Gas_Oil_Cooler.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"printf('\t example 16.3 \n');\n", +"printf('\t approximate values are mentioned in the book \n');\n", +"T1=250; // inlet hot fluid,F\n", +"T2=200; // outlet hot fluid,F\n", +"t1=80; // inlet cold fluid,F\n", +"t2=120; // outlet cold fluid,F\n", +"W=18000; // lb/hr\n", +"w=11950; // lb/hr\n", +"printf('\t 1.for heat balance \n')\n", +"C=0.53; // Btu/(lb)*(F)\n", +"Q=((W)*(C)*(T1-T2)); // Btu/hr\n", +"printf('\t total heat required for gas oil is : %.2e Btu/hr \n',Q);\n", +"c=1; // Btu/(lb)*(F)\n", +"Q=((w)*(c)*(t2-t1)); // Btu/hr\n", +"printf('\t total heat required for water is : %.2e Btu/hr \n',Q);\n", +"delt1=T2-t1; //F\n", +"delt2=T1-t2; // F\n", +"printf('\t delt1 is : %.0f F \n',delt1);\n", +"printf('\t delt2 is : %.0f F \n',delt2);\n", +"LMTD=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));\n", +"printf('\t LMTD is :%.0f F \n',LMTD);\n", +"X=((delt1)/(delt2));\n", +"printf('\t ratio of two local temperature difference is : %.2f \n',X);\n", +"Fc=0.47; // from fig.17\n", +"Kc=0.27; \n", +"Tc=((T2)+((Fc)*(T1-T2))); // caloric temperature of hot fluid,F\n", +"printf('\t caloric temperature of hot fluid is : %.0f F \n',Tc);\n", +"tc=((t1)+((Fc)*(t2-t1))); // caloric temperature of cold fluid,F\n", +"printf('\t caloric temperature of cold fluid is : %.0f F \n',tc);\n", +"printf('\t hot fluid:shell side,gas oil \n');\n", +"ID=3.068; // in, table 11\n", +"OD=1.9; // in, table 11\n", +"af=0.0175; // fin cross section,table 10\n", +"aa=((3.14*ID^2/(4))-(3.14*OD^2/(4))-(24*af))/(144);\n", +"printf('\t flow area is : %.4f ft^2 \n',aa);\n", +"p=(3.14*(OD))-(24*0.035)+(24*0.5*2);\n", +"printf('\t wetted perimeter : %.2f in \n',p);\n", +"De=(4*aa*12/(p));\n", +"printf('\t De : %.4f ft \n',De);\n", +"Ga=(W/aa); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Ga);\n", +"mu1=2.5*2.42; // at 224F,lb/(ft)*(hr), from fig.14\n", +"Rea=((De)*(Ga)/mu1); // reynolds number\n", +"printf('\t reynolds number is : %.2e \n',Rea);\n", +"jf=18.4; // from fig.16.10\n", +"Z=0.25; // Z=k*((c)*(mu1)/k)^(1/3), fig 16\n", +"Hf=((jf)*(1/De)*(Z)); // Hf=(hf/phya),using eq.6.15,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t individual heat transfer coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',Hf);\n", +"printf('\t cold fluid:inner tube side,water \n');\n", +"D=0.134; // ft\n", +"row=62.5;\n", +"at=(3.14*D^2/(4));\n", +"printf('\t flow area is : %.4f ft^2 \n',at);\n", +"Gt=(w/(at)); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Gt);\n", +"V=(Gt/(3600*row));\n", +"printf('\t V is : %.2f fps \n',V);\n", +"mu2=0.72*2.42; // at 99F,lb/(ft)*(hr)\n", +"Ret=((D)*(Gt)/mu2); // reynolds number\n", +"printf('\t reynolds number is : %.1e \n',Ret);\n", +"hi=(970*0.82); // fig 25\n", +"printf('\t hi : %.0f Btu/(hr)*(ft^2)*(F) \n',hi);\n", +"printf('\t calculation of tfw \n');\n", +"// Tc-tfw=40F assumption from fig 14\n", +"tfw=184;\n", +"mufw=3.5; // cp, at 184F\n", +"phya=(2.5/mufw)^0.14;\n", +"printf('\t phya is : %.2f \n',phya); // from fig.24\n", +"hf=(Hf)*(phya); // from eq.6.36\n", +"printf('\t Correct hf to the surface at the OD is : %.1f Btu/(hr)*(ft^2)*(F) \n',hf);\n", +"Rdo=0.002;\n", +"Rf=(1/hf);\n", +"printf('\t Rf : %.4f \n',Rf);\n", +"hf1=(1/(Rdo+Rf)); // eq 16.37\n", +"printf('\t hf1 : %.1f \n',hf1);\n", +"hfi1=255; // fig 16.9\n", +"hfi2=(hf1*5.76); // eq 16.38 and fig 16.9,((Af+Ao)/(Ai))=5.76 from previous prblm\n", +"printf('\t hfi2 : %.0f \n',hfi2);\n", +"Rmetal=(hfi2-hfi1)/(hfi2*hfi1); // eq 16.39\n", +"printf('\t Rmetal : %.5f \n',Rmetal);\n", +"phyt=1; // for cooling water\n", +"Rdi=0.003;\n", +"Ri=(1/hi);\n", +"printf('\t Ri : %.5f \n',Ri);\n", +"hi1=(1/(Rdi+Ri)); // eq 16.40\n", +"printf('\t hi1 : %.1f \n',hi1);\n", +"UDi=(hi1*hfi1)/(hi1+hfi1); // eq 16.41\n", +"printf('\t UDi : %.0f \n',UDi);\n", +"// To obtain the true flux the heat load must be divided by the actual heat-transfer surface.For a 1}2-in. IPS pipe there are 0.422 ft2/lin foot, from table 11\n", +"// trial\n", +"Ai=(Q/(UDi*LMTD)); // LMTD=delt\n", +"printf('\t Ai : %.1f ft^2 \n',Ai);\n", +"L=(Ai/0.422);\n", +"printf('\t length of pipe required : %.1f lin ft \n',L);\n", +"// Use two 20-ft hairpins = 80 lin ft\n", +"Ai1=(80*0.422); // ft^2\n", +"r=(Q/Ai1);\n", +"printf('\t Q/Ai1 : %.2e Btu/(hr)*(ft^2) \n',r);\n", +"deltf=(r/hfi2);\n", +"deltdo=(r*Rdo/5.76);\n", +"printf('\t annulus film : %.1f \n',deltf);\n", +"printf('\t annulus dirt : %.1f \n',deltdo);\n", +"d=deltf+deltdo; // d=Tc-tfw\n", +"deltmetal=(r*Rmetal);\n", +"deltdi=(r*Rdi);\n", +"delti=(r/hi);\n", +"printf('\t Tc-tfw : %.1f \n',d);\n", +"printf('\t fin and tube metal : %.1f \n',deltmetal);\n", +"printf('\t tube side dirt : %.1f \n',deltdi);\n", +"printf('\t tubeside film : %.1f \n',delti);\n", +"Td=deltf+deltdo+deltmetal+deltdi+delti;\n", +"printf('\t total temperature drop : %.1f F \n',Td);\n", +"printf('\t pressure drop for annulus \n');\n", +"De1=0.0359; // ft\n", +"Rea1=(De1*Ga/mu1);\n", +"printf('\t reynolds number : %.2e \n',Rea1);\n", +"f=0.00036; // fig 16.10\n", +"s=0.82; //using fig.6\n", +"delPs=((f*(Ga^2)*(80))/(5.22*(10^10)*(De1)*(s)*(phya))); // using eq.7.44,psi\n", +"printf('\t delPs is : %.1f psi \n',delPs);\n", +"printf('\t allowable delPa is 10 psi \n');\n", +"printf('\t pressure drop for inner pipe \n');\n", +"f=0.000192; // friction factor for reynolds number 65000, using fig.26\n", +"s=1;\n", +"delPt=((f*(Gt^2)*(80))/(5.22*(10^10)*(0.134)*(s)*(1))); // using eq.7.45,psi\n", +"printf('\t delPt is : %.1f psi \n',delPt);\n", +"printf('\t allowable delPa is 10 psi \n');\n", +"//end" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 16.4: Calculation_of_a_Longitudinal_Fin_Shell_and_tube_Exchanger.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"printf('\t example 16.4 \n');\n", +"printf('\t approximate values are mentioned in the book \n');\n", +"T1=250; // inlet hot fluid,F\n", +"T2=100; // outlet hot fluid,F\n", +"t1=80; // inlet cold fluid,F\n", +"t2=100; // outlet cold fluid,F\n", +"W=30000; // lb/hr\n", +"w=50500; // lb/hr\n", +"printf('\t 1.for heat balance \n')\n", +"C=0.225; // Btu/(lb)*(F)\n", +"Q=((W)*(C)*(T1-T2)); // Btu/hr\n", +"printf('\t total heat required for oxygwn is : %.2e Btu/hr \n',Q);\n", +"c=1; // Btu/(lb)*(F)\n", +"Q=((w)*(c)*(t2-t1)); // Btu/hr\n", +"printf('\t total heat required for water is : %.2e Btu/hr \n',Q);\n", +"delt1=T2-t1; //F\n", +"delt2=T1-t2; // F\n", +"printf('\t delt1 is : %.0f F \n',delt1);\n", +"printf('\t delt2 is : %.0f F \n',delt2);\n", +"LMTD=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));\n", +"printf('\t LMTD is :%.1f F \n',LMTD);\n", +"R=((T1-T2)/(t2-t1));\n", +"printf('\t R is : %.1f \n',R);\n", +"S=((t2-t1)/(T1-t1));\n", +"printf('\t S is : %.4f \n',S);\n", +"printf('\t FT is 0.87 \n'); // from fig 18\n", +"delt=(0.87*LMTD); // F\n", +"printf('\t delt is : %.1f F \n',delt);\n", +"Tc=(T2+T1)/(2); // caloric temperature of hot fluid,F\n", +"printf('\t caloric temperature of hot fluid is : %.0f F \n',Tc);\n", +"tc=((t1)+(t2))/(2); // caloric temperature of cold fluid,F\n", +"printf('\t caloric temperature of cold fluid is : %.0f F \n',tc);\n", +"printf('\t hot fluid:shell side,oxygen \n');\n", +"ID=19.25; // in, table 11\n", +"OD=1; // in, table 11\n", +"as=((3.14*ID^2/(4))-(70*3.14*OD^2/(4))-(70*20*0.035*0.5))/(144);\n", +"printf('\t flow area is : %.2f ft^2 \n',as);\n", +"p=(70*3.14*(OD))-(70*20*0.035)+(70*20*0.5*2);\n", +"printf('\t wetted perimeter : %.2e in \n',p);\n", +"De=(4*as*12/(p));\n", +"printf('\t De : %.3f ft \n',De);\n", +"Gs=(W/as); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Gs);\n", +"mu1=0.0545; // at 175F,lb/(ft)*(hr), from fig.15\n", +"Res=((De)*(Gs)/mu1); // reynolds number\n", +"printf('\t reynolds number is : %.3e \n',Res);\n", +"jH=59.5; // from fig.16.10a\n", +"k=0.0175;\n", +"Z=0.89; // Z=((c)*(mu1)/k)^(1/3), fig\n", +"hf=((jH)*(k/De)*(Z)); //using eq.6.15,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t individual heat transfer coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',hf);\n", +"Rdo=0.003;\n", +"hdo=(1/Rdo);\n", +"hf1=(hdo*hf)/(hdo+hf); // eq 16.37\n", +"printf('\t hf1 : %.1f \n',hf1);\n", +"hfi1=142; // fig 16.9\n", +"printf('\t cold fluid:inner tube side,water \n');\n", +"at1=0.479; // table 10\n", +"L=16;\n", +"Nt=70;\n", +"n=4;\n", +"at=((Nt*at1)/(144*n)); // total area,ft^2,from eq.7.48\n", +"printf('\t flow area is : %.4f ft^2 \n',at);\n", +"D=0.0652; // ft\n", +"row=62.5;\n", +"Gt=(w/(at)); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Gt);\n", +"V=(Gt/(3600*row));\n", +"printf('\t V is : %.2f fps \n',V);\n", +"mu2=1.94; // at 90F,lb/(ft)*(hr)\n", +"Ret=((D)*(Gt)/mu2); // reynolds number\n", +"printf('\t reynolds number is : %.2e \n',Ret);\n", +"hi=(940*0.96); // fig 25\n", +"printf('\t hi : %.0f Btu/(hr)*(ft^2)*(F) \n',hi);\n", +"Rdi=0.003;\n", +"hdi=(1/Rdi);\n", +"hi1=(hdi*hi)/(hdi+hi);\n", +"printf('\t hi1 : %.0f Btu/(hr)*(ft^2)*(F) \n',hi1);\n", +"UDi=((hfi1)*(hi1)/(hi1+hfi1)); // eq 16.41,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t overall coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',UDi);\n", +"A2=0.2048; // actual surface supplied for each tube,ft^2,from table 10\n", +"A=(Nt*L*A2); // ft^2\n", +"printf('\t total surface area is : %.0f ft^2 \n',A);\n", +"UDi1=((Q)/((A)*(delt)));\n", +"printf('\t design overall coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',UDi1);\n", +"Re=(1/UDi1)-(1/UDi);\n", +"printf('\t excess fouling factor : %.5f \n',Re);\n", +"Ro=9.27; //Adding to the outside fouling factor\n", +"Rdo1=Rdo+(Re*Ro);\n", +"printf('\t Rdo : %.4f \n',Rdo1);\n", +"hf2=(hf/(1+(hf*Rdo1)));\n", +"printf('\t hf2 : %.1f \n',hf2);\n", +"hfi2=113;\n", +"UDi2=((hfi2)*(hi1)/(hi1+hfi2)); // eq 16.41,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t overall coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',UDi2);\n", +"printf('\t pressure drop for annulus \n');\n", +"De1=0.0433; // ft\n", +"Res1=(De1*Gs/mu1);\n", +"printf('\t reynolds number : %.2e \n',Res1);\n", +"f=0.00025; // fig 16.10\n", +"s=0.00133;\n", +"delPs=((f*(Gs^2)*(L))/(5.22*(10^10)*(De1)*(s)*(1))); // using eq.7.44,psi\n", +"printf('\t delPs is : %.1f psi \n',delPs);\n", +"printf('\t allowable delPa is 2 psi \n');\n", +"printf('\t pressure drop for inner pipe \n');\n", +"f=0.00021; // friction factor for reynolds number 29100, using fig.26\n", +"s=1;\n", +"delPt=((f*(Gt^2)*(L)*(n))/(5.22*(10^10)*(0.0625)*(s)*(1))); // using eq.7.45,psi\n", +"printf('\t delPt is : %.0f psi \n',delPt);\n", +"printf('\t allowable delPa is 10 psi \n');\n", +"//end" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 16.5: Calculation_of_a_Transverse_fin_Air_Cooler.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"printf('\t example 16.5 \n');\n", +"printf('\t approximate values are mentioned in the book \n');\n", +"T1=250; // inlet hot fluid,F\n", +"T2=200; // outlet hot fluid,F\n", +"t1=150; // inlet cold fluid,F\n", +"t2=190; // outlet cold fluid,F\n", +"W=100000; // lb/hr\n", +"w=31200; // lb/hr\n", +"printf('\t 1.for heat balance \n')\n", +"C=0.25; // Btu/(lb)*(F)\n", +"Q=((W)*(C)*(T1-T2)); // Btu/hr\n", +"printf('\t total heat required for air is : %.2e Btu/hr \n',Q);\n", +"c=1; // Btu/(lb)*(F)\n", +"Q=((w)*(c)*(t2-t1)); // Btu/hr\n", +"printf('\t total heat required for water is : %.2e Btu/hr \n',Q);\n", +"delt1=T2-t1; //F\n", +"delt2=T1-t2; // F\n", +"printf('\t delt1 is : %.0f F \n',delt1);\n", +"printf('\t delt2 is : %.0f F \n',delt2);\n", +"LMTD=((delt2-delt1)/((2.3)*(log10(delt2/delt1))));\n", +"printf('\t LMTD is :%.1f F \n',LMTD);\n", +"R=((T1-T2)/(t2-t1));\n", +"printf('\t R is : %.1f \n',R);\n", +"S=((t2-t1)/(T1-t1));\n", +"printf('\t S is : %.4f \n',S);\n", +"printf('\t FT is 0.985 \n'); // from fig 18\n", +"delt=(0.985*LMTD); // F\n", +"printf('\t delt is : %.1f F \n',delt);\n", +"Tc=(T2+T1)/(2); // caloric temperature of hot fluid,F\n", +"printf('\t caloric temperature of hot fluid is : %.0f F \n',Tc);\n", +"tc=((t1)+(t2))/(2); // caloric temperature of cold fluid,F\n", +"printf('\t caloric temperature of cold fluid is : %.0f F \n',tc);\n", +"Af=(3.14*2*8*12*(1.75^2-1^2))/(4);\n", +"Ao=((3.14*1*12)-(3.14*1*8*0.035*12));\n", +"printf('\t fin surface is : %.0f in^2/lin ft \n',Af);\n", +"printf('\t bare tube surface is : %.1f in^2/lin ft \n',Ao);\n", +"A=(Af+Ao);\n", +"printf('\t total outside surface : %.1f ft^2/lin ft \n',A);\n", +"p=(2*3*2*8*12/8)+(((12)-(8*0.035*12))*(2));\n", +"printf('\t projected perimeter : %.1f in/ft \n',p);\n", +"De=(2*A/(3.14*p*12)); // eq 16.104\n", +"printf('\t De : %.3f ft \n',De);\n", +"// 21 tubes may be fit in one :vertical bank (Fig. 16.19b) ,20 tubes in alternating banks for triangular pitch\n", +"as=((4^2*12^2)-(21*1*48)-((21)*(2*0.035*3*8*48/8)))/(144); // fig 16.19\n", +"printf('\t flow area : %.1f ft^2 \n',as);\n", +"printf('\t hot fluid:shell side,oxygen \n');\n", +"Gs=(W/as); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Gs);\n", +"mu1=0.052; // at 225F,lb/(ft)*(hr), from fig.15\n", +"Res=((De)*(Gs)/mu1); // reynolds number\n", +"printf('\t reynolds number is : %.2e \n',Res);\n", +"jf=157; // from fig.16.18a\n", +"k=0.0183;\n", +"Z=0.89; // Z=((c)*(mu1)/k)^(1/3), fig\n", +"phys=1;\n", +"hf=((jf)*(k/De)*(Z)); //using eq.6.15,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t individual heat transfer coefficient is : %.1f Btu/(hr)*(ft^2)*(F) \n',hf);\n", +"Rdo=0.003;\n", +"hdo=(1/Rdo);\n", +"hf1=(hdo*hf)/(hdo+hf); // eq 16.37\n", +"printf('\t hf1 : %.1f \n',hf1);\n", +"hfi1=142; // fig 16.9\n", +"printf('\t cold fluid:inner tube side,water \n');\n", +"at1=0.546; // table 10\n", +"L=4;\n", +"Nt=21;\n", +"n=1;\n", +"at=((Nt*at1)/(144*n)); // total area,ft^2,from eq.7.48\n", +"printf('\t flow area is : %.4f ft^2 \n',at);\n", +"D=0.0695; // ft\n", +"row=62.5;\n", +"Gt=(w/(at)); // mass velocity,lb/(hr)*(ft^2)\n", +"printf('\t mass velocity is : %.2e lb/(hr)*(ft^2) \n',Gt);\n", +"V=(Gt/(3600*row));\n", +"printf('\t V is : %.2f fps \n',V);\n", +"mu2=0.895; // at 170F,lb/(ft)*(hr)\n", +"Ret=((D)*(Gt)/mu2); // reynolds number\n", +"printf('\t reynolds number is : %.2e \n',Ret);\n", +"hi=(710*0.94); // fig 25\n", +"printf('\t hi : %.0f Btu/(hr)*(ft^2)*(F) \n',hi);\n", +"Rdi=0.003;\n", +"hdi=(1/Rdi);\n", +"hi1=(hdi*hi)/(hdi+hi); // 16.40\n", +"printf('\t hi1 : %.0f Btu/(hr)*(ft^2)*(F) \n',hi1);\n", +"k1=60; // table 3 , for brass\n", +"// yb=0.00146 ft\n", +"X=((0.875-0.5)/12)*(21.5/(60*0.00146))^(1/2);\n", +"printf('\t X :%.2f \n',X);\n", +"nf=0.91; // from fig 16.13a , by comparing X value\n", +"Ai=0.218; // ft^2/ft\n", +"hfi2=((nf*Af/144)+(Ao/144))*(hf1/Ai); // eq 16.34\n", +"printf('\t hfi2 : %.0f \n',hfi2);\n", +"UDi=((hfi2)*(hi1)/(hi1+hfi2)); // eq 16.41,Btu/(hr)*(ft^2)*(F)\n", +"printf('\t overall coefficient is : %.0f Btu/(hr)*(ft^2)*(F) \n',UDi);\n", +"A=(21*4*Ai); // ft^2\n", +"printf('\t inside surface per bank is : %.1f ft^2 \n',A);\n", +"Ai1=(Q/(UDi*delt));\n", +"printf('\t Ai1 : %.0f ft^2 \n',Ai1);\n", +"Nb=(Ai1/A);\n", +"printf('\t number of banks : %.0f \n',Nb);\n", +"Vn=(4*4*1.95/12)-(41*3.14*1*4/(2*4*144))-((41*3.14*0.035*8*4/(144*2*4))*(1.75^2-1^2)); // fig 16.19b\n", +"printf('\t net free volume : %.2f ft^3 \n',Vn);\n", +"Af1=(41*2.34*4/2);\n", +"printf('\t frictional surface : %.0f ft^2 \n',Af1);\n", +"printf('\t pressure drop for annulus \n');\n", +"De1=(4*Vn/Af1); // ft\n", +"printf('\t De1 : %.2f ft \n',De1);\n", +"Res1=(De1*Gs/mu1);\n", +"printf('\t reynolds number : %.2e \n',Res1);\n", +"f=0.0024; // fig 16.18b\n", +"s=0.000928;\n", +"Lp=1.95;\n", +"R1=0.538; // R1=(De1/ST)^(0.4)\n", +"R2=1; // R2=(SL/ST)^0.6\n", +"delPs=((f*(Gs^2)*(Lp)*(R1)*(R2))/(5.22*(10^10)*(De1)*(s)*(1)));\n", +"printf('\t delPs is : %.2f psi \n',delPs);\n", +"printf('\t pressure drop for inner pipe \n');\n", +"f=0.0002; // friction factor for reynolds number 30400, using fig.26\n", +"s=1;\n", +"delPt=((f*(Gt^2)*(L)*(Nb))/(5.22*(10^10)*(0.0695)*(s)*(1))); // using eq.7.45,psi\n", +"printf('\t delPt is : %.2f psi \n',delPt);\n", +"//end" + ] + } +], +"metadata": { + "kernelspec": { + "display_name": "Scilab", + "language": "scilab", + "name": "scilab" + }, + "language_info": { + "file_extension": ".sce", + "help_links": [ + { + "text": "MetaKernel Magics", + "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" + } + ], + "mimetype": "text/x-octave", + "name": "scilab", + "version": "0.7.1" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |