From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 905/CH2/EX2.12/2_12.sce | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100755 905/CH2/EX2.12/2_12.sce

(limited to '905/CH2/EX2.12/2_12.sce')

diff --git a/905/CH2/EX2.12/2_12.sce b/905/CH2/EX2.12/2_12.sce
new file mode 100755
index 000000000..7b6e92a31
--- /dev/null
+++ b/905/CH2/EX2.12/2_12.sce
@@ -0,0 +1,48 @@
+clear;
+clc;
+
+// Illustration 2.12
+// Page: 131
+
+printf('Illustration 2.12 -  Page: 131\n\n');
+
+// solution
+//*****Data*****//
+// a-water    b-dry air
+D = 25.4*10^-3; // [Internal diameter of tower, m]
+Z = 1.5; // [length of the wetted section, m]
+Gy = 10; // [mass velocity of air, kg/square m.s]
+Tair = 308; // [K]
+Twater = 295; // [K]
+P = 101.3; // [kPa]
+M_a = 18; // [gram/mole]
+M_b = 29; // [gram/mole]
+R = 8.314; // [cubic m.Pa/mole.K]
+//*****//
+
+// The water vapor partial pressure at the interface remains constant at the vapor pressure of liquid water at 295 K, which is pa1 = Pa = 2.64 kPa
+// The water vapor partial pressure at the bulk of the gas phase increases from pA2 = pAin = 0 for the dry inlet air to pa2= pAout for the air leaving the tower 
+Pa = 2.64; // [kPa]
+
+Gm = Gy/M_b; // [Assuming that gas phase is basically dry air, kmole/square m.s]
+// The properties of dry air at 308 K and 1 atm are (from example 2.9)
+row = 1.14; // [kg/cubic m]
+u = 1.92*10^-5; // [kg/m.s]
+D_ab = 0.242*10^-4; // [square m/s]
+Sc = 0.692; // [Schmidt number]
+
+Re = Gy*D/u; // [Renoylds number]
+
+if(Re<35000 & Re>2000)
+// From equation 2.74
+Sh = 0.023*Re^0.83*Sc^0.44; // [Sherwood number]    
+
+printf("Sherwood number is %f\n\n",Sh);
+else()
+    printf('We cannot use equation 2.74')
+end
+
+c = P/(R*Tair); // [kmole/cubic m]
+// Now using equation 2.89
+Pa_out = Pa*(1-exp((-4*Sh*Z*c*D_ab)/(Gm*D^2))); // [kPa]
+printf("The partial pressure of water in the air leaving the tower is %e kPa\n\n",Pa_out);
\ No newline at end of file
-- 
cgit