{
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{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 2 : Review of basic concepts"
]
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 2.1 Page No : 29"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import math\n",
"\n",
"# Variables\n",
"R = 8.314;\t\t\t #universal gas constant in J/molK\n",
"t1 = 300.;\t\t\t #initial temperature of gas in K\n",
"p1 = 0.1;\t\t\t #initial pressure of the gas in MPa\n",
"p2 = 0.5;\t\t\t #pressure of gas after heating in MPa\n",
"p3 = 0.1;\t\t\t #pressure of gas after expansion in MPa\n",
"n = 1.; \t\t\t #number of moles of gas in mole\n",
"\n",
"# Calculations\n",
"w1 = 0*n; \t\t\t # Calculations of work done by the gas during heating in kJ (since dv = 0)\n",
"t2 = t1*(p2/p1);\t\t\t # Calculations of temperature of gas after heating in K\n",
"t3 = t2;\t\t \t # Calculations of temperature of gas after expansion in K (constant temperature expansion)\n",
"volume2 = p2/p3;\t\t\t # Calculations of ratio of volume of gas after expansion to the volume of gas after heating (no unit)\n",
"w2 = (R*t2*math.log(volume2)*n)/1000\n",
"volume3 = t3/t1;\t\t\n",
"w3 = (R*t1*(1-volume3)*n)/1000\n",
"work_net = w1+w2+w3;\t\t\t # Calculations of net work done by the gas for the process in kJ\n",
"\n",
"# Results\n",
"print ' Work done during heating process:Work from 1-2 = %d kJ '%(w1);\n",
"print ' Work done during constant temperature expansion: Work from 2-3 = %.3f kJ '%(w2);\n",
"print ' Work done during constant pressure compression: Work from 3-1 = %.3f kJ '%(w3);\n",
"print ' Net work done by the gas during the process = %.3f kJ '%(work_net);\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Work done during heating process:Work from 1-2 = 0 kJ \n",
" Work done during constant temperature expansion: Work from 2-3 = 20.071 kJ \n",
" Work done during constant pressure compression: Work from 3-1 = -9.977 kJ \n",
" Net work done by the gas during the process = 10.095 kJ \n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"Example 2.2 Page No : 30"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variables\n",
"v1 = 0.1;\t\t\t #volume of gas initially present in the cylinder in m**3\n",
"p1 = 0.1;\t\t\t #initial pressure of gas in MPa\n",
"p_atm = 0.1;\t\t #atmospheric pressure acting on the piston in MPa\n",
"v2 = 0.3;\t\t\t #volume of gas after heating in m**3\n",
"p2 = 0.6;\t\t\t #pressure of gas after heating in MPa\n",
"\n",
"# Calculations\n",
"work = ((p1+p2)*(v2-v1)*10**6)/(2*1000);\t\t\t # Calculations of work done by the gas in kJ \n",
"\n",
"# Results\n",
"print ' The work done by the gas = %d kJ'%(work);\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
" The work done by the gas = 70 kJ\n"
]
}
],
"prompt_number": 4
}
],
"metadata": {}
}
]
}