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clc;
warning("off");
printf("\n\n example5.9 - pg166");
// given
v=1; //[cm/sec] - volume velocity or bulk velocity
vol=1; //[cm^3] - volume
na=2; // moles of a
nb=3; // moles of b
nc=4; // moles of c
mma=2; //molecular weight of a
mmb=3; //molecular weight of b
mmc=4; //molecular weight of c
ma=na*mma; //[g] weight of a
mb=nb*mmb; //[g] weight of b
mc=nc*mmc; //[g] weight of c
NabyA=2+2; //[mol/cm^2*s] - molar flux = diffusing flux +convected flux
NbbyA=-1+3; //[mol/cm^2*s] - molar flux = diffusing flux +convected flux
NcbyA=0+4; //[mol/cm^2*s] - molar flux = diffusing flux +convected flux
NtbyA=NabyA+NbbyA+NcbyA; //[mol/cm^2*s] - total molar flux
// on a mass basis,these corresponds to
nabyA=4+4; //[g/cm^2*s]; - mass flux = diffusing flux +convected flux
nbbyA=-3+9; //[g/cm^2*s]; - mass flux = diffusing flux +convected flux
ncbyA=0+16; //[g/cm^2*s]; - mass flux = diffusing flux +convected flux
ntbyA=nabyA+nbbyA+ncbyA; //[g/cm^2*s] - total mass flux
// concentrations are expressed in molar basis
CA=na/vol; //[mol/cm^3]
CB=nb/vol; //[mol/cm^3]
CC=nc/vol; //[mol/cm^3]
CT=CA+CB+CC; //[mol/cm^3] - total concentration
// densities are on a mass basis
pa=ma/vol; //[g/cm^3]
pb=mb/vol; //[g/cm^3]
pc=mc/vol; //[g/cm^3]
pt=pa+pb+pc; //[g/cm^3]
Ua=NabyA/CA; //[cm/sec];
Ub=NbbyA/CB; //[cm/sec];
Uc=NcbyA/CC; //[cm/sec];
// the same result will be obtained from dividing mass flux by density
Uz=(pa*Ua+pb*Ub+pc*Uc)/(pa+pb+pc);
printf("\n\n Uz=%fcm/sec",Uz);
Uzstar=(NtbyA/CT);
printf("\n\n Uz*=%fcm/sec",Uzstar);
printf("\n\n for this example both Uz and Uz* are slightly greater than the volume velocity of 1cm/sec, because there is a net molar and mass diffusion in the positive direction.");
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