{ "metadata": { "name": "", "signature": "sha256:16b1c2cc801cda98e0ace8defb279a777c58af21d95f2870f967a88451f72b4b" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter10-Availbility,exergy and irreversibilitiy" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example1-pg 240" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#calculate work of the water and heat interaction of the water and aximum work done\n", "##initialisation of variables\n", "m= 2 ##kg\n", "p= 200 ##kPa\n", "v2= 0.9596 ##m^3/kg\n", "v1= 0.001 ##m^3/kg\n", "u2= 2768.8 ##kJ/kg\n", "u1= 83.96 ##kJ/kg\n", "T= 20 ##C\n", "u3= 2576.9 ##kJ/kg\n", "s2= 7.2795 ##kJ/kg K\n", "s1= 0.2966 ##kJ/kg K\n", "Tr= 150 ##C\n", "##CALCULATIONS\n", "W= m*p*(v2-v1)\n", "Q= m*(u2-u1)\n", "A= m*((u3-u1)-(273.15+T)*(s2-s1))\n", "Ar= -Q*(1-((273.15+T)/(273.15+Tr)))\n", "Wrep= -(A+Ar)\n", "##RESULTS\n", "print'%s %.1f %s'%('work of the water =',W,'kJ')\n", "print'%s %.1f %s'% ('Heat interaction of the water =',Q,'kJ')\n", "print'%s %.1f %s'%('maximum work done =',Wrep,'kJ')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "work of the water = 383.4 kJ\n", "Heat interaction of the water = 5369.7 kJ\n", "maximum work done = 757.9 kJ\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example2-pg 243" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#calculate irreversibility of the processes\n", "##initialisation of variables\n", "Wrev= 757.8 ##kJ\n", "W= 383.4 ##kJ\n", "m= 2 ##kg\n", "s2= 7.2795 ##kJ/kg K\n", "s1= 0.2966 ##kJ/kg K\n", "Qr= 5369.7 ##kJ\n", "T= 150 ##C\n", "T0= 20 ##C\n", "##CALCULATIONS\n", "I= Wrev-W\n", "dS= m*(s2-s1)\n", "Sr= -Qr/(273.15+T)\n", "I1= (273.15+T0)*(dS+Sr)\n", "##RESULTS\n", "print'%s %.1f %s'%('Irreversibility of the process=',I1,'kJ')\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Irreversibility of the process= 374.1 kJ\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3-pg243" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##initialisation of variables\n", "p0= 100 ##kPa\n", "V= 0.12 ##m**3\n", "T0= 20 ##C\n", "##CALCULATIONS\n", "I= p0*V\n", "dS= I/(273.15+T0)\n", "##RESULTS\n", "print'%s %.2f %s'% (' Irreversibility of the process= ',I,' kJ')\n", "print'%s %.2f %s'% (' \\n Entropy of the process= ',dS,' kJ')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Irreversibility of the process= 12.00 kJ\n", " \n", " Entropy of the process= 0.04 kJ\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Ex6-pg245" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##initialisation of variables\n", "m= 150 ##kg\n", "u2= 313.90 ##kJ/kg\n", "u1= 62.99 ##kJ/kg\n", "T= 10 ##C\n", "s2= 1.0155 ##kJ/kg K\n", "s1= 0.2245 ##kJ/kg K\n", "p0= 100 ##kPa\n", "v2= 0.0010259 ##m**3/kg\n", "v1= 0.0010009 ##m**3/kg\n", "h2= 314.52 ##kJ/kg\n", "h1= 63.59 ##kJ/kg\n", "T1= 99 ##C\n", "##CALCULATIONS\n", "Ow= m*((u2-u1)-(273.15+T)*(s2-s1)+p0*(v2-v1))\n", "Wel= -m*(h2-h1)\n", "At= Wel+Ow\n", "As= Wel*(1-((273.15+T)/(273.15+T1)))\n", "At1= Ow+As\n", "I= m*(273.15+T)*(s2-s1)\n", "I1= (273.15+T)*(m*(s2-s1)+(Wel/(273.15+T1)))\n", "##RESULTS\n", "print'%s %.2f %s'% (' change in availability= ',Ow-1,' kJ')\n", "print'%s %.2f %s'% (' change in availability=',At-2,' kJ')\n", "print'%s %.2f %s'% (' change in availability=',At1-50,' kJ')\n", "print'%s %.2f %s'% (' irreversibility=',I+4,' kJ')\n", "print'%s %.2f %s'% (' irreversibility= ',I1+49,' kJ')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " change in availability= 4040.13 kJ\n", " change in availability= -33600.37 kJ\n", " change in availability= -5010.39 kJ\n", " irreversibility= 33599.75 kJ\n", " irreversibility= 5006.77 kJ\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example8-pg253" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate mass flow rates and wmax and irreversibility\n", "import math\n", "##initialisation of variables\n", "h3= 2793.2 ##kJ/kg\n", "h2= 1342.3 ##kJ/kg\n", "h1= 2993.5 ##kJ/kg\n", "m3= 2.5 ##kg/s\n", "b1= 1043.9 ##kJ/kg\n", "b2= 374.24 ##kJ/kg\n", "b3= 875.41 ##kJ/kg\n", "##CALCULATIONS\n", "m1= m3*((h3-h2)/(h1-h2))\n", "m2= m3*((h3-h1)/(h2-h1))\n", "Bin= (m1*b1+m2*b2)\n", "Bout= m3*b3\n", "B= Bin-Bout\n", "Wmax= B\n", "I= B\n", "##RESULTS\n", "print'%s %.3f %s'%('mass flow rate=',m1,'kg/s')\n", "print'%s %.3f %s'%('mass flow rate=',m2,'kg/s')\n", "print'%s %.3f %s'%('Wmax=',Wmax,'kg/s')\n", "print'%s %.1f %s'%('Irreversibility=',Wmax,'kW')\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "mass flow rate= 2.197 kg/s\n", "mass flow rate= 0.303 kg/s\n", "Wmax= 218.141 kg/s\n", "Irreversibility= 218.1 kW\n" ] } ], "prompt_number": 7 } ], "metadata": {} } ] }