diff options
Diffstat (limited to 'Heat_Transfer_In_SI_Units_by_J_P_Holman/11-Mass_Transfer.ipynb')
| -rw-r--r-- | Heat_Transfer_In_SI_Units_by_J_P_Holman/11-Mass_Transfer.ipynb | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/Heat_Transfer_In_SI_Units_by_J_P_Holman/11-Mass_Transfer.ipynb b/Heat_Transfer_In_SI_Units_by_J_P_Holman/11-Mass_Transfer.ipynb new file mode 100644 index 0000000..b5f9836 --- /dev/null +++ b/Heat_Transfer_In_SI_Units_by_J_P_Holman/11-Mass_Transfer.ipynb @@ -0,0 +1,243 @@ +{ +"cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Chapter 11: Mass Transfer" + ] + }, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 11.1: diffusion_coefficient_for_co2.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"clear;\n", +"clc;\n", +"printf('\t\t\tExample Number 11.1\n\n\n');\n", +"// diffusion coefficient for co2\n", +"// Example 11.1(page no.-583)\n", +"// solution\n", +"\n", +"T = 25+273.15;// [K] temperature of air\n", +"Vco2 = 34.0;// molecular volume of co2\n", +"Vair = 29.0;// molecular volume of air\n", +"Mco2 = 44;// molecular weight of co2\n", +"Mair = 28.9;// molecular weight of air\n", +"P = 1.01325*10^(5);// [Pa] atmospheric pressure\n", +"// using equation (11-2)\n", +"D = 435.7*T^(1.5)*(((1/Mco2)+(1/Mair))^(1/2))/(P*(Vco2^(1/3)+Vair^(1/3))^(2));\n", +"printf('value of diffusion coefficient for co2 in air is %f square centimeter/s',D);" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 11.2: diffusion_coefficient_for_co2.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"clear;\n", +"clc;\n", +"printf('\t\t\tExample Number 11.2\n\n\n');\n", +"// diffusion coefficient for co2\n", +"// Example 11.2(page no.-586-587)\n", +"// solution\n", +"\n", +"T = 25+273.15;// [K] temperature of air\n", +"p = 1.01325*10^(5);// [Pa] atmospheric pressure\n", +"pw1 = 3166.7618901;// [Pa] partial pressure at the bottom of test tube\n", +"pw2 = 0;// [Pa] partial pressure at the top of test tube\n", +"pa1 = p-pw1;// [Pa] \n", +"pa2 = p-pw2;// [Pa]\n", +"D = .256*10^(-4);// [square meter/s] diffusion coefficient\n", +"Mw = 18;// [g] molecular weight of water\n", +"A = 22*((5*10^(-3))^(2))/7;// [square meter] area of test tube\n", +"R = 8314;// [J/mol K]gas constant\n", +"// using equation(11-16)\n", +"mw = (D*p*Mw*A/(R*T*0.15))*log(pa2/pa1);// mass flow rate\n", +"printf(' mass flow rate is %e kg/s',mw);" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 11.3: Wet_bulb_temperature.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"clear;\n", +"clc;\n", +"printf('\t\t\tExample Number 11.3\n\n\n');\n", +"// Wet-bulb temperature\n", +"// Example 11.3(page no.-590-591)\n", +"// solution\n", +"\n", +"Pg = 2107;// [Pa] from steam table at 18.3 degree celcius\n", +"Pw = Pg*18;// [Pa]\n", +"Rw = 8315;// [J/mol K] gas constant\n", +"Tw = 273.15+18.3;// [K]\n", +"RHOw = Pw/(Rw*Tw);// [kg/cubic meter]\n", +"Cw = RHOw;// [kg/cubic meter]\n", +"RHOinf = 0;// since the free stream is dry air\n", +"Cinf = 0;\n", +"P = 1.01325*10^(5);// [Pa]\n", +"R = 287;// [J /kg K]\n", +"T = Tw;// [K]\n", +"RHO = P/(R*T);// [kg/cubic meter]\n", +"Cp = 1004;// [J/kg degree celsius]\n", +"Le = 0.845;\n", +"Hfg = 2.456*10^(6);// [J/kg]\n", +"// now using equation(11-31)\n", +"Tinf = (((Cw-Cinf)*Hfg)/(RHO*Cp*(Le^(2/3))))+Tw;// [K]\n", +"Tin = Tinf-273.15;// [degree celsius]\n", +"printf('temperature of dry air is %f degree celsius',Tin);\n", +"printf('\n\n these calculations are now recalculated the density at the arithmetic-average temperature between wall and free-stream conditions');\n", +"printf('\n\n with this adjustments these results are RHO = 1.143 kg/m^(3) and Tinf = 55.8 degree celcius');\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 11.4: relative_humidity_of_air_stream.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"clear;\n", +"clc;\n", +"printf('\t\t\tExample Number 11.4\n\n\n');\n", +"// relative humidity of air stream\n", +"// Example 11.4(page no.-591)\n", +"// solution\n", +"\n", +"// these data were taken from previous example\n", +"Rho = 1.212;// [kg/cubic meter]\n", +"Cp = 1004;// [J/kg]\n", +"Le = 0.845;\n", +"Tw = 18.3;// [degree celsius]\n", +"Tinf = 32.2;// [degree celsius]\n", +"Rhow = 0.015666;// [kg/cubic meter]\n", +"Cw = Rhow;// [kg/cubic meter]\n", +"Hfg = 2.456*10^(6);// [J/kg]\n", +"// we use eqn 11-31\n", +"Cinf = Cw-(Rho*Cp*Le^(2/3)*(Tinf-Tw)/Hfg);// [kg/cubic meter]\n", +"Rhoinf = Cinf;// [kg/cubic meter]\n", +"Rhog = 0.0342;// [kg/cubic meter]\n", +"RH = (Rhoinf/Rhog)*100;\n", +"printf(' relative humidity is therefore %f percentage',RH);\n", +"" + ] + } +, +{ + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 11.5: water_evaporation_rate.sce" + ] + }, + { +"cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], +"source": [ +"clear;\n", +"clc;\n", +"printf('\t\t\tExample Number 11.5\n\n\n');\n", +"// water evaporation rate\n", +"// Example 11.5(page no.-593-594)\n", +"// solution\n", +"\n", +"Ta = 38+273;// [K] temperature of atmospheric air\n", +"RH = 0.30;// relative humidity\n", +"u = 10;// [mi/h] mean wind speed\n", +"R = 0.287;// universal gas constant\n", +"Dw = 0.256*10^(-4);// [square meter/s] from table A-8(page no.-610)\n", +"rho_w = 1000;// [kg/cubic meter]\n", +"// for this calculation we can make use of equation(11-36). from thermodynamic steam tables\n", +"p_g = 6.545;// [kPa] at 38 degree celsius\n", +"p_s = p_g;// [kPa]\n", +"p_w = RH*p_s;// [kPa]\n", +"p_s = 1.933;// [in Hg]\n", +"p_w = 0.580;// [in Hg]\n", +"// also \n", +"u_bar = u*24;// [mi/day]\n", +"// equation(11-36) yields, with the application of the 0.7 factor\n", +"E_lp = 0.7*(0.37+0.0041*u_bar)*(p_s-p_w)^(0.88);// [in/day]\n", +"E_lp = E_lp*2.54/100;// [m/day]\n", +"// noting that standard pan has the diameter of 1.2m, we can use the figure to calculate the mass evaporation rate per unit area as\n", +"m_dot_w_by_A = E_lp*rho_w/24;// [kg/h square meter]\n", +"// as a matter of interest, we might calculate the molecular-diffusion rate of water vapour from equation(11-35), taking z1 as the 1.5m dimension above the standard pan.\n", +"z1 = 1.5;// [m]\n", +"// since rho = p/(R*T)\n", +"// equation(11-35) can be written as \n", +"m_dot_w_by_A1 = 0.622*Dw*p_g*3600/(R*Ta*z1);// [kg/h square meter]\n", +"printf('evaporation rate on the land under these conditions is %e kg/h square meter',m_dot_w_by_A1);\n", +"\n", +"" + ] + } +], +"metadata": { + "kernelspec": { + "display_name": "Scilab", + "language": "scilab", + "name": "scilab" + }, + "language_info": { + "file_extension": ".sce", + "help_links": [ + { + "text": "MetaKernel Magics", + "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" + } + ], + "mimetype": "text/x-octave", + "name": "scilab", + "version": "0.7.1" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |