clear; clc; // Illustration 12.6 // Page: 685 printf('Illustration 12.6 - Page: 685\n\n'); // Solution //***Data***// Y1 = 0.01;// [kg water/kg dry air] Gs = 1.1;// [kg dry air/square m.s] dia = 13.5/1000;// [m] l = 13/1000;// [m] zS = 50/1000;// [m] Density_S = 600;// [kg dry solid/square m.s] a = 280;// [square m/cubic m] //************// // From Fig 7.5 (Pg 232) Yas = 0.031;// [kg water/kg dry air] Gav = Gs+(Gs*(Y1+Yas)/2);// [kg/square m.s] viscosity_air = 1.9*10^(-5);// [kg/m.s] Area = (2*%pi*dia^2/4)+(%pi*dia*l);// [square m] dp = (Area/%pi)^0.5;// [m] // From Table 3.3 (Pg 74) Re = dp*Gav/viscosity_air; e = 1-(dp*a/6);// [fraction voids] jD = (2.06/e)*Re^(-0.575); // For air water mixture: Sc = 0.6; // From Eqn. 12.33: kY = jD*Gs/Sc^(2/3);// [kg H2O/square m.s.deltaX] // From Eqn. 12.30: NtG = kY*a*zS/Gs; // From Eqn. 12.25: Nmax = Gs*(Yas-Y1);// [kg/square m.s] // From Eqn. 12.31: N = Nmax*(1-exp(-NtG));// [kg water evaporated/square m.s] Y2 = (Yas-Y1)*(N/Nmax)+Y1;// [kg water/kg dry air] // From Fig 7.5 (Pg 232) Tempas = 33;// [OC] // From eqn. 12.2: Rate = N/(Density_S*zS);// [kg H2O/(kg dry solid).s] printf("Humidity of the exit air: %f kg water/kg dry air\n",Y2); printf("Temparature of exit air: %d OC\n",Tempas); printf("Rate of Drying: %e kg H2O/(kg dry solid).s\n",Rate);