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diff --git a/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter19.ipynb b/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter19.ipynb deleted file mode 100755 index a351bd14..00000000 --- a/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter19.ipynb +++ /dev/null @@ -1,353 +0,0 @@ -{ - "cells": [ - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "# Chapter 19 - Psychrometry" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 1: pg 625" - ] - }, - { - "cell_type": "code", - "execution_count": 3, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - "Example 19.1\n", - " (a) The mass of water vapor in the humid air is (kg) = 0.0087\n", - " The specific volume of humid air is (m^3/kg) = 0.811\n", - " (b) The mass of water vapor in the humid air is (kg) = 0.029\n", - " The specific volume of humid air is (m^3/kg) = 0.881\n", - " On the warm day the air contains 2.5 times the mass of water vapor as on the cool day \n", - "\n" - ] - } - ], - "source": [ - "#pg 625\n", - "print('Example 19.1');\n", - "\n", - "# aim : To compare the moisture content and the true specific volumes of atmosphere air \n", - "# (a) temperature is 12 C and the air is saturaded\n", - "# (b) temperature is 31 C and air is .75 saturated\n", - "\n", - "# Given values\n", - "P_atm = 101.4;# atmospheric pressure, [kN/m^2]\n", - "R = .287;# [kJ/kg K]\n", - "\n", - "# solution\n", - "# (a)\n", - "T = 273+12;# air temperature, [K]\n", - "# From steam table at 12 C\n", - "p = 1.4;# [kN/m^2]\n", - "vg = 93.9;# [m^3/kg]\n", - "pa = P_atm-p;# partial pressure of the dry air, [kN/m^2]\n", - "va = R*T/pa;# [m^3/kg]\n", - "\n", - "mw = va/vg;# mass of water vapor in the air,[kg]\n", - "v = va/(1+mw);# specific volume of humid air, [m^3/kg]\n", - "\n", - "print ' (a) The mass of water vapor in the humid air is (kg) = ',round(mw,4)\n", - "print ' The specific volume of humid air is (m^3/kg) = ',round(v,3)\n", - "\n", - "# (b)\n", - "x = .75;# dryness fraction\n", - "T = 273.+31;# air temperature, [K]\n", - "# From steam table\n", - "p = 4.5;# [kN/m^2]\n", - "vg = 31.1;# [m^3/kg]\n", - "pa = P_atm-p;# [kN/m^2]\n", - "va = R*T/pa;# [m^3/kg]\n", - "mw1= va/vg;# mass of water vapor in the air, [kg]\n", - "mw_actual = mw1*x;# actual mass of vapor, [kg]\n", - "v = va/(1+mw_actual);# true specific volume of humid air,[m^3/kg] \n", - "\n", - "print ' (b) The mass of water vapor in the humid air is (kg) = ',round(mw1,4)\n", - "print ' The specific volume of humid air is (m^3/kg) = ',round(v,3)\n", - "\n", - "ewv = mw_actual/mw ;\n", - "print ' On the warm day the air contains ',round(ewv,1),' times the mass of water vapor as on the cool day \\n'\n", - "\n", - "# End\n" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 2: pg 626" - ] - }, - { - "cell_type": "code", - "execution_count": 4, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - "Example 19.2\n", - " (a) The partial pressure of vapor is (kN/m^2) = 1.521\n", - " The partial pressure of dry air is (kN/m^2) = 98.479\n", - " (b) The specific humidity of the mixture is (kg/kg dry air) = 0.0096\n", - " (c) The composition of the mixture is = 0.99\n" - ] - } - ], - "source": [ - "#pg 626\n", - "print('Example 19.2');\n", - "\n", - "# aim : To determine\n", - "# (a) the partial pressures of the vapor and the dry air\n", - "# (b) the specific humidity of the mixture\n", - "# (c) the composition of the mixture\n", - "\n", - "# Given values\n", - "phi = .65;# Relative humidity\n", - "T = 273.+20;# temperature, [K]\n", - "p = 100.;# barometric pressure, [kN/m^2]\n", - "\n", - "# solution\n", - "# (a)\n", - "# From the steam table at 20 C\n", - "pg = 2.34;# [kN/m^2]\n", - "ps = phi*pg;# partial pressure of vapor, [kN/m^2]\n", - "pa = p-ps;# partial pressure of dry air, [kN/m^2]\n", - "print ' (a) The partial pressure of vapor is (kN/m^2) = ',ps\n", - "print ' The partial pressure of dry air is (kN/m^2) = ',pa\n", - "\n", - "# (b)\n", - "# from equation [15]\n", - "omega = .622*ps/(p-ps);# specific humidity of the mixture\n", - "print ' (b) The specific humidity of the mixture is (kg/kg dry air) = ',round(omega,4)\n", - "\n", - "# (c)\n", - "# using eqn [1] from section 19.2\n", - "y = 1/(1+omega);# composition of the mixture\n", - "print ' (c) The composition of the mixture is = ',round(y,2)\n", - "\n", - "# End\n" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 3: pg 627" - ] - }, - { - "cell_type": "code", - "execution_count": 5, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - "Example 19.3\n", - " (a) The specific humidity is (kg/kg air) = 0.0119\n", - " (b) The dew point is (C) = 10.08\n", - " (c) The degree of superheat is (C) = 14.92\n", - " (d) The mass of condensate is (kg/kg dry air) = 0.003\n", - "there is calculation mistake in the book so answer is no matching\n" - ] - } - ], - "source": [ - "#pg 627\n", - "print('Example 19.3');\n", - "\n", - "# aim : To determine\n", - "# (a) the specific humidity\n", - "# (b) the dew point\n", - "# (c) the degree of superheat of the superheated vapor\n", - "# (d) the mass of condensate formed per kg of dry air if the moist air is cooled to 12 C\n", - "\n", - "# Given values\n", - "t = 25.;# C\n", - "T = 273.+25;# moist air temperature, [K]\n", - "phi = .6;# relative humidity\n", - "p = 101.3;# barometric pressure, [kN/m^2]\n", - "R = .287;# [kJ/kg K]\n", - "\n", - "# solution\n", - "# (a)\n", - "# From steam table at 25 C\n", - "pg = 3.17;# [kN/m^2]\n", - "ps = phi*pg;# partial pressure of the vapor, [kN/m^2]\n", - "omega = .622*ps/(p-ps);# the specific humidity of air\n", - "\n", - "print ' (a) The specific humidity is (kg/kg air) = ',round(omega,4)\n", - "\n", - "# (b)\n", - "# Dew point is saturated temperature at ps is,\n", - "t_dew = 16.+2*(1.092-1.817)/(2.062-1.817);# [C]\n", - "print ' (b) The dew point is (C) = ',round(t_dew,2)\n", - "\n", - "# (c)\n", - "Dos = t-t_dew;# degree of superheat, [C]\n", - "print ' (c) The degree of superheat is (C) = ',round(Dos,2)\n", - "\n", - "# (d)\n", - "# at 25 C\n", - "pa = p-ps;# [kN/m^2]\n", - "va = R*T/pa;# [m^3/kg]\n", - "# at 16.69 C\n", - "vg = 73.4-(73.4-65.1)*.69/2;# [m^3/kg]\n", - "ms1= va/vg; \n", - "# at 12 C\n", - "vg = 93.8;# [m^3/kg]\n", - "ms2 = va/vg;\n", - "\n", - "m = ms1-ms2;# mas of condensate\n", - "print ' (d) The mass of condensate is (kg/kg dry air) = ',round(m,4)\n", - "\n", - "print 'there is calculation mistake in the book so answer is no matching'\n", - "\n", - "# End\n" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 4: pg 630" - ] - }, - { - "cell_type": "code", - "execution_count": 6, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - " Example 19.4\n", - " (a) The volume of air required is (m^3/h) = 107057.0\n", - " (b) The mass of water added is (kg/h) = 276.7\n", - " (c) The heat transfer required by dry air is (MJ/h) = 458.226\n", - " (d) The heat transferred required for vapor+supply water is (MJ/h) = 721.688\n", - " there is minor variation in the answer reported in the book due to rounding off error\n" - ] - } - ], - "source": [ - "#pg 630\n", - "print(' Example 19.4');\n", - "\n", - "# aim : To determine\n", - "# (a) the volume of external saturated air\n", - "# (b) the mass of air\n", - "# (c) the heat transfer\n", - "# (d) the heat transfer required by the combind water vapour\n", - "\n", - "# given values\n", - "Vb = 56000.;# volume of building, [m^3]\n", - "T2 = 273.+20;# temperature of air in thebuilding, [K]\n", - "phi = .6;# relative humidity\n", - "T1 = 8+273.;# external air saturated temperature, [K]\n", - "p0 = 101.3;# atmospheric pressure, [kN/m^2]\n", - "cp = 2.093;# heat capacity of saturated steam, [kJ/kg K]\n", - "R = .287;# gas constant, [kJ/kg K]\n", - "\n", - "# solution\n", - "# from steam table at 20 C saturation pressure of steam is,\n", - "pg = 2.34;# [kN/m^2]\n", - "\n", - "# (a)\n", - "pvap = phi*pg;# partial pressure of vapor, [kN/m^2] \n", - "P = p0-pvap;# partial pressure of air, [kN/m^2]\n", - "V = 2*Vb;# air required, [m^3]\n", - "# at 8 C saturation pressure ia\n", - "pvap = 1.072;# [kN/m^2]\n", - "P2 = p0-pvap;# partial pressure of entry at 8 C, [kN/m^2]\n", - "\n", - "# using P1*V1/T1=P2*V2/T2;\n", - "V2 = P*V*T1/(T2*P2);# air required at 8 C, [m^3/h]\n", - "print ' (a) The volume of air required is (m^3/h) = ',round(V2)\n", - "\n", - "# (b)\n", - "# assuming\n", - "pg = 1.401;# pressure, [kN/m^2]\n", - "Tg = 273.+12;# [K]\n", - "vg = 93.8;# [m^3/kg]\n", - "# at constant pressure\n", - "v = vg*T2/Tg;# volume[m^3/kg]\n", - "mv = V/v;# mass of vapor in building at 20 C, [kg/h]\n", - "# from steam table at 8 C\n", - "vg2 = 121.;# [m^3/kg]\n", - "mve = V2/vg2;# mass of vapor supplied with saturated entry air, [kg/h]\n", - "mw = mv-mve;# mass of water added, [kg/h]\n", - "print ' (b) The mass of water added is (kg/h) = ',round(mw,1)\n", - "\n", - "# (c)\n", - "# for perfect gas\n", - "m = P2*V2/(R*T1);# [kg/h]\n", - "Cp = .287;# heat capacity, [kJ/kg K]\n", - "Q = m*Cp*(T2-T1);# heat transfer by dry air,[kJ/h]\n", - "print ' (c) The heat transfer required by dry air is (MJ/h) = ',round(Q*10**-3,3)\n", - "\n", - "# (d)\n", - "# from steam table\n", - "h1 = 2516.2;# specific enthalpy of saturated vapor at 8 C,[kJ/kg]\n", - "hs = 2523.6;# specific enthalpy of saturated vapor at 20 C, [kJ/kg]\n", - "h2 = hs+cp*(T2-T1);# specific enthalpy of vapor at 20 c, [kJ/kg]\n", - "Q1 = mve*(h2-h1);# heat transfer required for vapor, [kJ]\n", - "\n", - "# again from steam table\n", - "hf1 = 33.6;# [kJ/kg]\n", - "hg3 = 2538.2;# [kJ/kg]\n", - "Q2 = mw*(hg3-hf1);# heat transfer required for water, [kJ/h]\n", - "Qt = Q1+Q2;# total heat transfer, [kJ/h]\n", - "print ' (d) The heat transferred required for vapor+supply water is (MJ/h) = ',round(Qt*10**-3,3)\n", - "\n", - "print ' there is minor variation in the answer reported in the book due to rounding off error'\n", - "\n", - "# End\n" - ] - } - ], - "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": "2.7.11" - } - }, - "nbformat": 4, - "nbformat_minor": 0 -} |