initial commit / add all books

1 files changed, 187 insertions, 0 deletions

diff --git a/389/CH8/EX8.8/Example8_8.sce b/389/CH8/EX8.8/Example8_8.sce
new file mode 100755
index 000000000..bc98fbb0b
--- /dev/null
+++ b/389/CH8/EX8.8/Example8_8.sce
@@ -0,0 +1,187 @@
+clear;

+clc;

+

+// Illustration 8.8

+// Page: 317

+

+printf('Illustration 8.8 - Page: 317\n\n');

+

+// Solution

+

+//***Data***

+// a:NH3 b:air c:H2O

+ya = 0.416;// [mole fraction]

+yb = 0.584;// [mole fraction]

+G1 = 0.0339;// [kmol/square m.s]

+L1 = 0.271;// [kmol/square m.s]

+TempG1 = 20;// [OC]

+//********//

+

+// At 20 OC

+Ca = 36390;// [J/kmol]

+Cb = 29100;// [J/kmol]

+Cc = 33960;// [J/kmol]

+lambda_c = 44.24*10^6;// [J/kmol]

+// Enthalpy base = NH3 gas, H2O liquid, air at 1 std atm.

+Tempo = 20;// [OC]

+lambda_Ao = 0;// [J/kmol]

+lambda_Co = 44.24*10^6;// [J/kmol]

+

+// Gas in:

+Gb = G1*yb;// [kmol air/square m.s]

+Ya1 = ya/(1-ya);// [kmol NH3/kmol air]

+yc1 = 0;// [mole fraction]

+Yc1 = yc1/(1-yc1);// [kmol air/kmol NH]

+// By Eqn 8.58:

+Hg1 = (Cb*(TempG1-Tempo))+(Ya1*(Ca*(TempG1-Tempo))+lambda_Ao)+(Yc1*(Cc*(TempG1-Tempo)+lambda_Co));// [J/kmol air]

+

+// Liquid in:

+xa1 = 0;// [mole fraction]

+xc1 = 1;// [mole fraction]

+Hl1 = 0;// [J/kmol air]

+

+//Gas out:

+Ya2 = Ya1*(1-0.99);// [kmol NH3/kmol air]

+// Assume:

+TempG2 = 23.9;// [OC]

+yc2 = 0.0293;

+deff('[y] = f(Yc2)','y = yc2-(Yc2/(Yc2+Ya2+1))');

+Yc2 = fsolve(0.002,f);// [kmol H2O/kmol air]

+Hg2 = (Cb*(TempG2-Tempo))+(Ya2*(Ca*(TempG2-Tempo))+lambda_Ao)+(Yc2*(Cc*(TempG2-Tempo)+lambda_Co));// [J/kmol air]

+

+// Liquid out:

+Lc = L1-(Yc1*Gb);// [kmol/square m.s]

+La = Gb*(Ya1-Ya2);// [kmol/square m.s]

+L2 = La+Lc;// [kmol/square m.s]

+xa = La/L2;

+xc = Lc/L2;

+// At xa & tempo = 20 OC

+delta_Hs = -1709.6*1000;// [J/kmol soln]

+

+// Condition at the bottom of the tower:

+// Assume:

+TempL = 41.3;// {OC}

+// At(TempL+TempG1)/2:

+Cl = 75481;// [J/kmol]

+deff('[y] = f40(Cl)','y = Hl1+Hg1-((Gb*Hg2)+(L2*(Cl*(TempL-Tempo)+delta_Hs)))');

+Cl = fsolve(7,f40);// [J/kmol.K]

+

+// For the Gas:

+MavG = 24.02;// [kg/kmol]

+Density_G = 0.999;// [kg/cubic m]

+viscosity_G  =  1.517*10^(-5);// [kg/m.s]

+kG  =  0.0261;// [W/m.K]

+CpG  =  1336;// [J/kg.K]

+Dab  =  2.297*10^(-5);// [square m/s]

+Dac  =  3.084*10^(-5);// [square m/s]

+Dcb  =  2.488*10^(-5);// [square m/s]

+PrG  =  CpG*viscosity_G/kG;

+

+// For the liquid:

+MavL  =  17.97;// [kg/kmol]

+Density_L  =  953.1;// [kg/cubic m]

+viscosity_L  =  6.408*10^(-4);// [kg/m.s]

+Dal  =  3.317*10^(-9);// [square m/s]

+kl = 0.4777;// [W/m.K]

+ScL = viscosity_L/(Density_L*Dal);

+PrL = 5.72;

+sigma = 3*10^(-4);

+G_prime = G1*MavG;// [kg/square m.s]

+L_prime = L2*MavL;// [kg/square m.s]

+// From data of Chapter 6:

+Ds = 0.0472;// [m]

+a = 57.57;// [square m/cubic m]

+shiLt = 0.054;

+e = 0.75;

+// By Eqn. 6.71:

+eLo = e-shiLt;

+// By Eqn. 6.72:

+kL = (25.1*Dal/Ds)*(Ds*L_prime/viscosity_L)^0.45*ScL^0.5;// [m/s]

+c = Density_L/MavL;// [kmol/cubic m]

+Fl = kL*c;// [kmol/cubic m]

+// The heat mass transfer analogy of Eqn. 6.72:

+hL = (25.1*kl/Ds)*(Ds*L_prime/viscosity_L)^0.45*PrL^0.5;// [m/s]

+// The heat transfer analogy of Eqn. 6.69:

+hG = (1.195*G_prime*CpG/PrG^(2/3))*(Ds*G_prime/(viscosity_G*(1-eLo)))^(-0.36);// [W/square m.K]

+// To obtain the mass transfer coeffecients:

+Ra = 1.4;

+Rc = 1-Ra;

+// From Eqn. 8.83:

+Dam = (Ra-ya)/(Ra*((yb/Dab)+((ya+yc1)/Dac))-(ya/Dac));// [square m/s]

+Dcm = (Rc-yc1)/(Rc*((yb/Dcb)+((ya+yc1)/Dac))-(yc1/Dac));// [square m/s]

+ScGa = viscosity_G/(Density_G*Dam);

+ScGc = viscosity_G/(Density_G*Dcm);

+// By Eqn. 6.69:

+FGa = (1.195*G1/ScGa^(2/3))*(Ds*G_prime/(viscosity_G*(1-eLo)))^(-0.36);// [kmol/square m.K]

+FGc = (1.195*G1/ScGc^(2/3))*(Ds*G_prime/(viscosity_G*(1-eLo)))^(-0.36);// [kmol/square m.K]

+Ra = Ra-0.1;

+// From Eqn. 8.80:

+scf(14);

+for i = 1:3

+    deff('[yai] = f41(xai)','yai = Ra-(Ra-ya)*((Ra-xa)/(Ra-xai))^(Fl/FGa)');

+    xai = xa:0.01:0.10;

+    plot(xai,f41)

+    Ra = Ra+0.1;

+end

+xgrid();

+xlabel("Mole fraction NH3 in the liquid, xa");

+ylabel("Mole fraction NH3 in the gas ya");

+title("Operating Line curves");

+Rc = Rc-0.1;

+// From Eqn. 8.81:

+scf(15);

+for i = 1:3

+    deff('[yci] = f42(xci)','yci = Rc-(Rc-yc1)*((Rc-xc)/(Rc-xci))^(Fl/FGc)');

+    xci = xc:-0.01:0.85;

+    plot(xci,f42)

+    Rc = Rc+0.1;

+end

+xgrid();

+xlabel("Mole fraction H2O in the liquid, xc");

+ylabel("Mole fraction H2O in the gas, yc");

+title("Operating line Curves");

+// Assume:

+Tempi = 42.7;// [OC]

+// The data of Fig. 8.2 (Pg 279) & Fig 8.4 (Pg 319) are used to draw the eqb curve of Fig 8.25 (Pg 320).

+// By interpolation of operating line curves with eqb line and the condition: xai+xci = 1;

+Ra = 1.38;

+Rc = 1-Ra;

+xai = 0.0786;

+yai = f41(xai);

+xci = 1-xai;

+yci = f42(xci);

+// From Eqn. 8.77:

+dYa_By_dZ = -(Ra*FGa*a/Gb)*log((Ra-yai)/(Ra-ya));// [kmol H2O/kmol air]

+// From Eqn. 8.78:

+dYc_By_dZ = -(Rc*FGc*a/Gb)*log((Rc-yci)/(Rc-yc1));// [kmol H2O/kmol air]

+// From Eqn. 8.82:

+hGa_prime = -(Gb*((Ca*dYa_By_dZ)+(Cc*dYc_By_dZ)))/(1-exp(Gb*((Ca*dYa_By_dZ)+(Cc*dYc_By_dZ))/(hG*a)));// [W/cubic m.K]

+// From Eqn. 8.79:

+dtG_By_dZ = -(hGa_prime*(TempG1-Tempi))/(Gb*(Cb+(Ya1*Ca)+(Yc1*Cc)));// [K/m]

+// When the curves of Fig. 8.2 (pg 279) & 8.24 (Pg 319) are interpolated for concentration xai and xci, the slopes are:

+mar = 0.771;

+mcr = 1.02;

+lambda_c = 43.33*10^6;// [J/kmol]

+// From Eqn. 8.3:

+Hai = Ca*(Tempi-Tempo)+lambda_Ao-(mar*lambda_c);// [J/kmol]

+Hci = Cc*(Tempi-Tempo)+lambda_Co-(mcr*lambda_c);// [J/kmol]

+// From Eqn. 8.76

+Tempi2 = TempL+(Gb/(hL*a))*(((Hai-Ca*(TempG1-Tempo)-lambda_Ao)*dYa_By_dZ)+((Hci-Cc*(TempG1-Tempo)-lambda_Co)*dYc_By_dZ)-((Cb+(Ya1*Ca)+(Yc1*Cc))*dtG_By_dZ));// [OC]

+// The value of Tempi obtained is sufficiently close to the value assumed earlier.

+

+deltaYa=-0.05;

+// An interval of deltaYa up the tower

+deltaZ = deltaYa/(dYa_By_dZ);// [m]

+deltaYc = (dYc_By_dZ*deltaZ);

+// At this level:

+Ya_next = Ya1+deltaYa;// [kmol/kmol air]

+Yc_next = Yc1+deltaYc;// [kmol H2O/kmol air]

+tG_next = TempG1+(dtG_By_dZ*deltaZ);// [OC]

+L_next = L1+Gb*(deltaYa+deltaYc);// [kmol/square m.s]

+xa_next = ((Gb*deltaYa)+(L1*xa))/L_next;// [mole fraction NH3]

+Hg_next = (Cb*(tG_next-Tempo))+(Ya_next*(Ca*(tG_next-Tempo))+lambda_Ao)+(Yc_next*(Cc*(tG_next-Tempo)+lambda_Co));// [J/kmol air]

+Hl_next = (L1*Hl1)+(Gb*(Hg_next-Hg2)/L_next);// [J/kmol]

+// The calculation are continued where the specified gas outlet composition are reached.

+// The packed depth is sum of all deltaZ

+Z = 1.58;// [m]

+printf("The packed depth is: %f m\n",Z);
\ No newline at end of file