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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 13: Gas Dynamics"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.1, page no. 259"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#initialization\n",
      "v = 2000.0                      #ft/sec\n",
      "P = 14.7                        #lb/in^2\n",
      "g = 1.4\n",
      "T = 10+460.0                    #R\n",
      "\n",
      "#calculation\n",
      "c = math.sqrt(g*32.2*53.3*T)\n",
      "Nm = v/c\n",
      "Tratio = 1+ (g-1)/2 *Nm**2\n",
      "Tt = Tratio*T\n",
      "Pratio = (Tratio)**(g/(g-1))\n",
      "Pt = Pratio*P\n",
      "\n",
      "#result\n",
      "print \"Stagnation temperature  =  %d R\" %Tt\n",
      "print \"Stagnation pressure  =  \", round(Pt, 1), \"lb/in^2\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Stagnation temperature  =  802 R\n",
        "Stagnation pressure  =   95.8 lb/in^2\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.2, page no. 261"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#initialization\n",
      "A = 0.3                         #ft^2\n",
      "P = 30.0                        #lb/in^2\n",
      "T = 160+460.0                   #R\n",
      "Mn = 0.82\n",
      "g = 1.4\n",
      "\n",
      "#calculation\n",
      "w = A*144*P*math.sqrt(g*32.2) *Mn*(1+ (g-1)/2.0 *(Mn)**2)**(-3)/math.sqrt(53.3*T)\n",
      "\n",
      "#result\n",
      "print \"Mass flow  = \", round(w, 1), \"lbm/sec\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Mass flow  =  26.9 lbm/sec\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.3, page no. 263"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#initialization\n",
      "Mn = 3.0\n",
      "Mni = 0.2\n",
      "w = 10.0                        #lbm/sec\n",
      "g = 1.4\n",
      "P = 200.0                       #lb/in^2\n",
      "T = 400+460.0                   #R\n",
      "\n",
      "#calculation\n",
      "Astar = w*math.sqrt(53.3*T) *((g+1)/2)**3 /(P*math.sqrt(g*32.2))\n",
      "A1ratio = (2.0/(g+1) + (g-1)*Mni**2 /(g+1))**3 /Mni\n",
      "A1 = A1ratio*Astar\n",
      "A2ratio = (2.0/(g+1) + (g-1)*Mn**2 /(g+1))**3 /Mn\n",
      "A2 = A2ratio*Astar\n",
      "Pexit = P/(1+ Mni*Mn**2)**(g/(g-1))\n",
      "\n",
      "#result\n",
      "print \"Throat Area  =  \", round(Astar, 2), \"in^2\"\n",
      "print \"Inlet Area  = \", round(A1, 2), \"in^2\"\n",
      "print \"Exit Area  = \", round(A2, 2), \"in^2\"\n",
      "print \"Exit pressure  = \", round(Pexit, 2), \"lb/in^2\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Throat Area  =   2.76 in^2\n",
        "Inlet Area  =  8.16 in^2\n",
        "Exit Area  =  11.67 in^2\n",
        "Exit pressure  =  5.44 lb/in^2\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.4, page no. 266"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#initialization\n",
      "Pi = 750.0                  #lb/in^2\n",
      "g = 1.25\n",
      "TA = 2.0                    #in^2\n",
      "r = 3.0\n",
      "\n",
      "#calculation\n",
      "Fstar = round(((g+1)*(2.0/(g+1))**5 *TA*750))\n",
      "Me = 2.45\n",
      "Fratio = round(((1+g*Me**2)/(Me*(math.sqrt(4.5+ (g**2 -1)*Me**2)))), 3)\n",
      "F2 = Fratio*Fstar\n",
      "Pratio = (1+ 0.2*Me**2)**5\n",
      "Fnstar = Fratio-((g+1)/2.0)**5 *r/(Pratio*2.25)\n",
      "Fn = Fnstar*Fstar\n",
      "\n",
      "#result\n",
      "print \"Internal rocket thrust  =  %d lb\" %F2 #answer in textbook is wrong\n",
      "print \"External thrust  =  %d lb\" %Fn #answer in textbook is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Internal rocket thrust  =  2316 lb\n",
        "External thrust  =  2229 lb\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.5, page no. 270"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#initialization\n",
      "Tt2 = 1620+460 #R\n",
      "Tt1 = 60+460 #R\n",
      "Mi = 0.2\n",
      "P = 40 #lb/in^2\n",
      "g = 1.35\n",
      "\n",
      "#calculation\n",
      "Tratio = Tt2/Tt1\n",
      "#From figure\n",
      "fM = 4*0.036\n",
      "NM2 = 0.49\n",
      "Pratio = 0.98/0.885\n",
      "Pt2 = P/Pratio\n",
      "\n",
      "#result\n",
      "print \"Final stagnation pressure  =  \", round(Pt2, 1), \"lb/in^2\"\n",
      "print \"Final mach number  = \", round(fM, 3)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Final stagnation pressure  =   36.1 lb/in^2\n",
        "Final mach number  =  0.144\n"
       ]
      }
     ],
     "prompt_number": 16
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 13.6, page no. 273"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#initialization\n",
      "M = 0.4\n",
      "l = 10.0                            #ft\n",
      "dia =  3.0                          #in\n",
      "P = 50.0                            #lb/in^2\n",
      "ff = 0.008\n",
      "T = 100+460.0                       #R\n",
      "\n",
      "#calculation\n",
      "constant =  4*ff*l/dia\n",
      "exitM = 2.9-constant\n",
      "Nm2 = 0.5\n",
      "Ptratio = 2.73/2.3\n",
      "Pt2 = P/Ptratio\n",
      "\n",
      "#result\n",
      "print \"Exit total pressure  =  \", round(Pt2, 1), \"lb/in^2\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Exit total pressure  =   42.1 lb/in^2\n"
       ]
      }
     ],
     "prompt_number": 17
    }
   ],
   "metadata": {}
  }
 ]
}