{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 9 : Theories of Mass Transfer" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.1.1 pgno31" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "The film thickness is cm 0.00765\n" ] } ], "source": [ "#initialization of variables\n", "p1 = 10. # pressure in atm\n", "H = 600. # henrys constant in atm\n", "c1 = 0 # gmol/cc\n", "N1 = 2.3*10**-6 # mass flux in mol/cm**2-sec\n", "c = 1./18. #total Concentration in g-mol/cc\n", "D = 1.9*10**-5 # Diffusion co efficient in cm**2/sec\n", "#Calculations\n", "c1i = (p1/H)*c # Component concentration in gmol/cc\n", "k = N1/(c1i-c1)#Mass transfer co efficient in cm/sec\n", "l = D/k # Film thickness in cm\n", "#Results\n", "print\"The film thickness is cm\",round(l,5)\n", "\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.2.1 pgno:34" ] }, { "cell_type": "code", "execution_count": 8, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "The contact time sec 3.9\n", "\n", "The surface resident time sec 3.0\n" ] } ], "source": [ "#initialization of variables\n", "D = 1.9*10**-5 #Diffusion co efficient in cm**2/sec\n", "k = 2.5*10**-3 # M.T.C in cm/sec\n", "from math import pi\n", "#Calculations\n", "Lbyvmax = 4*D/((k**2)*pi)#sec\n", "tou = D/k**2 # sec\n", "#Results\n", "print\"The contact time sec\",round(Lbyvmax,1)\n", "print\"\\nThe surface resident time sec\",round(tou,1)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.3.1 pgno:35" ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "The apparent m.t.c for the first case is cm/sec 0.000379885493042\n", "\n", "The apparent m.t.c for the second case is cm/sec 0.000742723884992\n", "\n", "The apparent is proportional to the power of of the velocity 0.61\n" ] } ], "source": [ "#initialization of variables\n", "const = 0.5 # The part of flow in the system which bypasses the region where the mass transfer occurs\n", "v1 = 1. # cm/sec\n", "al = 10**3\n", "k = 10**-3 # cm/sec\n", "v2 = 3. # cm/sec\n", "from math import log\n", "from math import exp\n", "#Calculations\n", "C1byC10first = const + (1-const)*(exp(-k*al/v1))# c1/c10\n", "appk1 = (v1/al)*(log(1/C1byC10first))# Apparent m.t.c for first case in cm/sec\n", "C1byC10second = const + (1-const)*(exp(-((3)**0.5)*k*al/v2))#c1/c10 in second case\n", "appk2 = (v2/al)*log(1/C1byC10second)# apparent m.t.c for second case in cm/sec\n", "power = log(appk2/appk1)/log(v2/v1)\n", "#Results\n", "print\"The apparent m.t.c for the first case is cm/sec\",appk1\n", "print\"\\nThe apparent m.t.c for the second case is cm/sec\",appk2\n", "print\"\\nThe apparent is proportional to the power of of the velocity\",round(power,2)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.4.1 pgno:37" ] }, { "cell_type": "code", "execution_count": 10, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "The average mass transfer coefficient is cm/sec 0.000431530124388\n" ] } ], "source": [ "#initialization of variables\n", "D = 1*10**-5 #cm**2/sec\n", "d = 2.3 # cm\n", "L = 14 # cm\n", "v0 = 6.1 # cm/sec\n", "#gamma(4./3.)=0.8909512761;\n", "#calculations\n", "k = ((3**(1./3.))/(0.8909512761))*((D/d))*(((d**2)*v0/(D*L))**(1./3.))# cm/sec\n", "#Results\n", "print\"The average mass transfer coefficient is cm/sec\",k\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.4.2 pgno:40" ] }, { "cell_type": "code", "execution_count": 6, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "The distance at which turbulent flow starts is cm 300.0\n", "\n", "The boundary layer for flow at this point is cm 300.0\n", "\n", "The boundary layer for concentration at this point is cm 300.0\n", "\n", "The local m.t.c at the leading edge and at the position of transistion is x10**-5 cm/sec 0.589714620247\n" ] } ], "source": [ "#initialization of variables\n", "tn = 300000 # turbulence number\n", "v0 = 10 # cm/sec\n", "p = 1 # g/cc\n", "mu = 0.01 # g/cm-sec\n", "delta = 2.5 #cm\n", "D = 1*10**-5 # cm**2/sec\n", "#Calculations\n", "x = tn*mu/(v0*p)# cm\n", "delta = ((280/13)**(1/2))*x*((mu/(x*v0*p))**(1/2))#cm\n", "deltac = ((D*p/mu)**(1/3))*delta#cm\n", "k = (0.323*(D/x)*((x*v0*p/mu)**0.5)*((mu/(p*D))**(1/3)))*10**5# x*10**-5 cm/sec\n", "#Results\n", "print\"The distance at which turbulent flow starts is cm\",x\n", "print\"\\nThe boundary layer for flow at this point is cm\",delta\n", "print\"\\nThe boundary layer for concentration at this point is cm\",deltac\n", "print\"\\nThe local m.t.c at the leading edge and at the position of transistion is x10**-5 cm/sec\",k\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python 2", "language": "python", "name": "python2" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 2 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython2", "version": "2.7.9" } }, "nbformat": 4, "nbformat_minor": 0 }