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diff --git a/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter18.ipynb b/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter18.ipynb deleted file mode 100755 index 696c7fa6..00000000 --- a/Basic_Engineering_Thermodynamics_by_Rayner_Joel/Chapter18.ipynb +++ /dev/null @@ -1,205 +0,0 @@ -{ - "cells": [ - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "# Chapter 18 - Refrigeration" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 1: pg 612" - ] - }, - { - "cell_type": "code", - "execution_count": 1, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - "Example 18.1\n", - " (a) The coefficient of performance of the refrigerator is = 4.49\n", - " (b) The mass flow of refrigerant/h is (kg) = 166.94\n", - " (c) The mass flow of water required is (kg/h) = 579.74\n", - "The answer is a bit different due to rounding off error in textbook\n" - ] - } - ], - "source": [ - "#pg 612\n", - "print('Example 18.1');\n", - "\n", - "# aim : To determine\n", - "# (a) the coefficient of performance\n", - "# (b) the mass flow of the refrigerant\n", - "# (c) the cooling water required by the condenser\n", - "import math\n", - "from math import log\n", - "# given values\n", - "P1 = 462.47;# pressure limit, [kN/m**2]\n", - "P3 = 1785.90;# pressure limit, [kN/m**2]\n", - "T2 = 273.+59;# entering saturation temperature, [K]\n", - "T5 = 273.+32;# exit temperature of condenser, [K]\n", - "d = 75*10**-3;# bore, [m]\n", - "L = d;# stroke, [m]\n", - "N = 8;# engine speed, [rev/s]\n", - "VE = .8;# olumetric efficiency\n", - "cpL = 1.32;# heat capacity of liquid, [kJ/kg K]\n", - "c = 4.187;# heat capacity of water, [kj/kg K]\n", - "\n", - "# solution\n", - "# from given table\n", - "# at P1\n", - "h1 = 231.4;# specific enthalpy, [kJ/kg]\n", - "s1 = .8614;# specific entropy,[ kJ/kg K\n", - "v1 = .04573;# specific volume, [m**3/kg]\n", - "\n", - "# at P3\n", - "h3 = 246.4;# specific enthalpy, [kJ/kg]\n", - "s3 = .8093;# specific entropy,[ kJ/kg K\n", - "v3 = .04573;# specific volume, [m**3/kg]\n", - "T3= 273+40;# saturation temperature, [K]\n", - "h4 = 99.27;# specific enthalpy, [kJ/kg]\n", - "# (a)\n", - "s2 = s1;# specific entropy, [kJ/kg k]\n", - "# using s2=s3+cpv*log(T2/T3)\n", - "cpv = (s2-s3)/log(T2/T3);# heat capacity, [kj/kg k]\n", - "\n", - "# from Fig.18.8\n", - "T4 = T3;\n", - "h2 = h3+cpv*(T2-T3);# specific enthalpy, [kJ/kg]\n", - "h5 = h4-cpL*(T4-T5);# specific enthalpy, [kJ/kg]\n", - "h6 = h5;\n", - "COP = (h1-h6)/(h2-h1);# coefficient of performance\n", - "print ' (a) The coefficient of performance of the refrigerator is = ',round(COP,2)\n", - "\n", - "# (b)\n", - "SV = math.pi/4*d**2*L;# swept volume of compressor/rev, [m**3]\n", - "ESV = SV*VE*N*3600;# effective swept volume/h, [m**3]\n", - "m = ESV/v1;# mass flow of refrigerant/h,[kg]\n", - "print ' (b) The mass flow of refrigerant/h is (kg) = ',round(m,2)\n", - "\n", - "# (c)\n", - "dT = 12;# temperature limit, [C]\n", - "Q = m*(h2-h5);# heat transfer in condenser/h, [kJ]\n", - "# using Q=m_dot*c*dT, so\n", - "m_dot = Q/(c*dT);# mass flow of water required, [kg/h]\n", - "print ' (c) The mass flow of water required is (kg/h) = ',round(m_dot,2)\n", - "\n", - "print 'The answer is a bit different due to rounding off error in textbook'\n", - "# End\n" - ] - }, - { - "cell_type": "markdown", - "metadata": {}, - "source": [ - "## Example 2: pg 614" - ] - }, - { - "cell_type": "code", - "execution_count": 2, - "metadata": { - "collapsed": false - }, - "outputs": [ - { - "name": "stdout", - "output_type": "stream", - "text": [ - "Example 18.2\n", - " (a) The mass flow of R401 is (kg/h) = 592.6\n", - " (b) The dryness fraction of R401 at the entry to the evaporator is = 0.244\n", - " (c) The power to driving motor is (kW) = 5.86\n", - " (d) The ratio of heat transferred from condenser to the power required to the motor is = 4.74 :1\n" - ] - } - ], - "source": [ - "#pg 614\n", - "print('Example 18.2');\n", - "\n", - "# aim : To determine\n", - "# (a) the mass flow of R401\n", - "# (b) the dryness fraction of R401 at the entry to the evaporator\n", - "# (c) the power of driving motor\n", - "# (d) the ratio of heat transferred from condenser to the power required to the motor\n", - "from math import log\n", - "# given values\n", - "P1 = 411.2;# pressure limit, [kN/m^2]\n", - "P3 = 1118.9;# pressure limit, [kN/m^2]\n", - "Q = 100*10**3;# heat transfer from the condenser,[kJ/h]\n", - "T2 = 273+60;# entering saturation temperature, [K]\n", - "\n", - "# given\n", - "# from given table\n", - "# at P1\n", - "h1 = 409.3;# specific enthalpy, [kJ/kg]\n", - "s1 = 1.7431;# specific entropy,[ kJ/kg K\n", - "\n", - "# at P3\n", - "h3 = 426.4;# specific enthalpy, [kJ/kg]\n", - "s3 = 1.7192;# specific entropy,[ kJ/kg K\n", - "T3 = 273.+50;# saturation temperature, [K]\n", - "h4 = 265.5;# specific enthalpy, [kJ/kg]\n", - "# (a)\n", - "s2 = s1;# specific entropy, [kJ/kg k]\n", - "# using s2=s3+cpv*log(T2/T3)\n", - "cpv = (s2-s3)/log(T2/T3);# heat capacity, [kj/kg k]\n", - "\n", - "# from Fig.18.8\n", - "h2 = h3+cpv*(T2-T3);# specific enthalpy, [kJ/kg]\n", - "Qc = h2-h4;# heat transfer from condenser, [kJ/kg]\n", - "mR401 = Q/Qc;# mass flow of R401, [kg]\n", - "print ' (a) The mass flow of R401 is (kg/h) = ',round(mR401,1)\n", - "\n", - "# (b)\n", - "hf1 = 219;# specific enthalpy, [kJ/kg]\n", - "h5 = h4;\n", - "# using h5=hf1+s5*(h1-hf1),so\n", - "x5 = (h5-hf1)/(h1-hf1);# dryness fraction\n", - "print ' (b) The dryness fraction of R401 at the entry to the evaporator is = ',round(x5,3)\n", - "\n", - "# (c)\n", - "P = mR401*(h2-h1)/3600/.7;# power to driving motor, [kW]\n", - "print ' (c) The power to driving motor is (kW) = ',round(P,2)\n", - "\n", - "# (d)\n", - "r = Q/3600./P;# ratio\n", - "print ' (d) The ratio of heat transferred from condenser to the power required to the motor is = ',round(r,2),\":1\"\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 -} |