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clear;
clc;
printf('FUNDAMENTALS OF HEAT AND MASS TRANSFER \n Incropera / Dewitt / Bergman / Lavine \n EXAMPLE 14.1 Page 884 \n')// Example 14.1
// Molar and mass fluxes of hydrogen and the relative values of the mass and thermal diffusivities for the three cases
T = 293 ;//[K] Temperature
Ma = 2 ;//[kg/kmol] Molecular Mass
//Table A.8 Hydrogen-Air Properties at 298 K
Dab1 = .41*10^-4; //[m^2/s] diffusion coefficient
//Table A.8 Hydrogen-Water Properties at 298 K
Dab2 = .63*10^-8; //[m^2/s] diffusion coefficient
//Table A.8 Hydrogen-iron Properties at 293 K
Dab3 = .26*10^-12; //[m^2/s] diffusion coefficient
//Table A.4 Air properties at 293 K
a1 = 21.6*10^-6; //[m^2/s] Thermal Diffusivity
//Table A.6 Water properties at 293 K
k = .603 ;//[W/m.K] conductivity
rho = 998 ;//[kg/m^3] Density
cp = 4182 ;//[J/kg] specific Heat
//Table A.1 Iron Properties at 300 K
a3 = 23.1 * 10^-6; //[m^2/s]
//Equation 14.14
//Hydrogen-air Mixture
DabT1 = Dab1*(T/298)^1.5; // [m^2/s] mass diffusivity
J1 = -DabT1*1; //[kmol/s.m^2] Total molar concentration
j1 = Ma*J1; //[kg/s.m^2] mass Flux of Hydrogen
Le1 = a1/DabT1; // Lewis Number Equation 6.50
//Hydrogen-water Mixture
DabT2 = Dab2*(T/298)^1.5; // [m^2/s] mass diffusivity
a2 = k/(rho*cp) ;//[m^2/s] thermal diffusivity
J2 = -DabT2*1 ;//[kmol/s.m^2] Total molar concentration
j2 = Ma*J2 ;//[kg/s.m^2] mass Flux of Hydrogen
Le2 = a2/DabT2 ;// Lewis Number Equation 6.50
//Hydrogen-iron Mixture
DabT3 = Dab3*(T/298)^1.5; // [m^2/s] mass diffusivity
J3 = -DabT3*1; //[kmol/s.m^2] Total molar concentration
j3 = Ma*J3; //[kg/s.m^2] mass Flux of Hydrogen
Le3 = a3/DabT3 ;// Lewis Number Equation 6.50
printf('\n Species a (m^2/s) Dab (m^2/s) Le ja (kg/s.m^2) \n Air %.1e %.1e %.2f %.1e \n Water %.1e %.1e %i %.1e \n Iron %.1e %.1e %.1e %.1e',a1,DabT1,Le1,j1,a2,DabT2,Le2,j2,a3,DabT3,Le3,j3);
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