1 files changed, 82 insertions, 0 deletions
diff --git a/497/CH16/EX16.5/Chap16_Ex5.sce b/497/CH16/EX16.5/Chap16_Ex5.sce
new file mode 100755
index 000000000..19b0b730b
--- /dev/null
+++ b/497/CH16/EX16.5/Chap16_Ex5.sce
@@ -0,0 +1,82 @@
+//Kunii D., Levenspiel O., 1991. Fluidization Engineering(II Edition). Butterworth-Heinemann, MA, pp 491
+
+//Chapter-16, Example 5, Page 425
+//Title: Solvent Recovery from Polymer Particles
+//==========================================================================================================
+
+clear
+clc
+
+//INPUT
+rhos=1600;//Density of solid in kg/m^3
+Cps=1.25;//Specific heat of solids in kJ/kg K
+Fo=0.5;//Flow rate of solids in kg/s
+Tsi=20;//Inital temperature of solids in degree C
+Qwi=1;//Initial moisture fraction in water
+Qwf=0.2;//Final moisture fraction in water
+Qhi=1.1;//Initial moisture fraction in heptane
+Qhf=0.1;//Final moisture fraction in heptane
+Tgi=240;//Initial temperature of gas in degee C
+Te=110;//Bed temperature in degree C
+ephsilonm=0.45;//Void fraction of fixed bed
+ephsilonf=0.75;//Void fraction of fluidized bed
+uo=0.6;//Superficial gas velocity in m/s
+di=0.08;//Diameter of tubes in m
+li=0.2;//Pitch for square arrangement
+hw=400;//Heat transfer coefficient in W/m^2 K
+Tc=238;//Temperature at which steam condenses in degree C
+//Specific heats in kJ/kg K
+Cwl=4.18;//Water liquid
+Cwv=1.92;//Water vapor
+Chl=2.05;//Heptane liquid
+Chv=1.67;//Heptane vapor
+//Latent heat of vaporization in kJ/kg
+Lw=2260;//Water
+Lh=326;//Heptane
+//Density of vapor in kg/m^3 at operating conditions
+rhow=0.56;//Water
+rhoh=3.1;//Heptane
+Lf=1.5;//Length of fixed bed in m
+t=140;//Half-life of heptane in s
+L=1.5;//Length of tubes in heat exchanger
+pi=3.14;
+
+//CALCULATION
+//(a) Dryer without Internals
+xw=(Qwi-Qwf)/(Qhi-Qhf);//Water-heptane weight ratio
+xv=((Qwi-Qwf)/18)/((Qhi-Qhf)/100);//Water-heptane volume ratio
+T=(Qwi-Qwf)/18+(Qhi-Qhf)/100;//Total volume
+rhogbar=((Qwi-Qwf)/18)/T*rhow+((Qhi-Qhf)/100)/T*rhoh;//Mean density of the vapor mixture
+Cpgbar=(((Qwi-Qwf)/18)/T)*rhow*Cwv+(((Qhi-Qhf)/100)/T)*rhoh*Cwv;//Mean specific heat of vapor mixture
+//Volumetric flow of recycle gas to the dryer in m^3/s from Eqn.(53)
+x=(Cpgbar*(Tgi-Te))^-1*[Fo*(Qwi-Qwf)*[Lw+Cwl*(Te-Tsi)]+Fo*(Qhi-Qhf)*[Lh+Chl*(Te-Tsi)]+Fo*(Cps*(Te-Tsi))];
+r=Fo*[(Qwi-Qwf)/rhow+(Qhi-Qhf)/rhoh};//Rate of formation of vapor in bed
+uo1=uo*(x/(x+r));//Superficial velocity just above the distributor
+At=x/uo1;//Cross-sectional area of bed
+dt=sqrt(4/pi*At);//Diameter of bed
+B=-log(Qwf/Qwi)/t;//Bed height from Eqn.(63)
+tbar=((Qhi/Qhf)-1)/B;//Mean residence time of solids
+W=Fo*tbar;//Weight of bed
+Lm=W/(At*(1-ephsilonm)*rhos);//Static bed height
+Lf=(Lm*(1-ephsilonm))/(1-ephsilonf);//Height of fluidized bed
+
+//(b) Dryer with internal heaters
+f=1/8;//Flow rate is 1/8th the flow rate of recirculation gas as in part (a)
+x1=f*x;//Volumetric flow of recycle gas to the dryer in m^3/s from Eqn.(53)
+uo2=uo*(x1/(x1+r));//Superficial velocity just above the distributor
+Abed=x1/uo2;//Cross-sectional area of bed
+q=[Fo*(Qwi-Qwf)*[Lw+Cwl*(Te-Tsi)]+Fo*(Qhi-Qhf)*[Lh+Chl*(Te-Tsi)]+Fo*(Cps*(Te-Tsi))]-Abed*uo2*Cpgbar*(Tgi-Te);//Heat to be added from energy balance of Eqn.(53)
+Aw=q*10^3/(hw*(Tc-Te));//Total surface area of heat exchanger tubes
+Lt=Aw/(pi*di);//Total length of tubes
+Nt=Lt/L;//Total number of tubes
+Atubes=Nt*(pi/4*di^2);//Total cross-sectional area of tubes
+Atotal=Abed+Atubes;//Total cross-sectional area of tube filled dryer
+d=sqrt(Atotal*pi/4);//Diameter of vessel
+li=sqrt(Atotal/Nt);//Pitch for square array of tubes
+
+//OUTPUT
+printf('\n\t\t\tBed diameter(m)\tRecycle vapor flow(m^3/s)');
+printf('\nWithout internal heater\t%f\t%f',dt,x);
+printf('\nWith heating tubes\t%f\t%f',d,x1);
+
+//====================================END OF PROGRAM ======================================================
+\ No newline at end of file