{
"cells": [
 {
		   "cell_type": "markdown",
	   "metadata": {},
	   "source": [
       "# Chapter 6: Using Entropy"
	   ]
	},
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.10: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"m1 = 5.00                                           // initial mass in kg\n",
"P1 = 5.00                                           // initial pressure in bar\n",
"T1 = 500.00                                         // initial temperature in kelvin\n",
"P2 = 1.00                                           // final pressure in bar\n",
"// From table A-22\n",
"pr1 = 8.411\n",
"// Using this value of pr2 and interpolation in table A-22\n",
"T2 = 317.00                                         // in kelvin\n",
"// Calculations \n",
"pr2 = (P2/P1)*pr1\n",
"m2 = (P2/P1)*(T1/T2)*m1\n",
"// Results\n",
"printf('The amount of mass remaining in the tank  is %f kg',m2)\n",
"printf('and its temperature is %f kelvin.',T2);"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.11: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 1.00                                              // inlet pressure in bar\n",
"T1 = 593.00                                            // inlet temperature in kelvin\n",
"P2 = 1.00                                              // exit pressure in bar\n",
"eta =0.75                                              // turbine efficiency\n",
"// From table A-4\n",
"h1 = 3105.6                                            // in Kj/kg\n",
"s1 = 7.5308                                            // in kj/kg.k\n",
"// From table A-4 at 1 bar\n",
"h2s = 2743.00                                          // in kj/kg\n",
"// Calculations\n",
"w = eta*(h1 - h2s)\n",
"// Result\n",
"printf( ' The work developed per unit mass of steam flowing through is %f kJ/kg.',w);"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.12: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 3.00                                  // pressure of air entering in bar\n",
"T1 = 390.00                                // temperature of air entering in kelvin\n",
"P2 = 1.00                                  // pressure of exit air\n",
"Wcvdot = 74.00                             // work developed in kj/kg\n",
"// From table A-22,at 390k\n",
"h1 = 390.88                                // in kj/kg\n",
"pr1 = 3.481\n",
"// From interpolation table A-22\n",
"h2s = 285.27                               // in kj/kg\n",
"// calculations\n",
"pr2 = (P2/P1)*pr1\n",
"Wcvdots = h1 - h2s\n",
"eta = Wcvdot/Wcvdots\n",
"// Result\n",
"printf( ' The turbine efficiency is %.4f ',eta)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.13: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 1.00                                       // pressure of entering steam in Mpa\n",
"T1 = 593.00                                     // temperature of entering steam in kelvin\n",
"V1 = 30.00                                      // velocity of entering steam in m/s\n",
"P2 = 0.3                                        // pressure of exit steam in Mpa\n",
"T2 = 453.00                                     // temperature of exit steam in kelvin\n",
"// From table A-4, at T1 = 593 kelvin and P1 = 1 Mpa;\n",
"// and at T2 = 453 kelvin and P2 = .3 Mpa\n",
"h1 = 3093.9                                     // in kj/kg\n",
"s1 = 7.1962                                     // in kj/kg.k\n",
"h2 = 2823.9                                     // in kj/kg\n",
"// Interpolating in table A-4\n",
"h2s = 2813.3                                    // in kj/kg\n",
"// Calculations\n",
"V2squareby2 = h1 - h2 + (V1**2)/2000\n",
"V2squareby2s = h1 - h2s + (V1**2)/2000\n",
"eta = V2squareby2/V2squareby2s\n",
"// Results\n",
"printf( ' The nozzle efficiency is %.4f',eta)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.14: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"// From table A-9\n",
"h1 = 249.75                                             // in kj/kg\n",
"h2 = 294.17                                             // in kj/kg\n",
"mdot = 0.07                                             // in kg/s\n",
"// From table A-9\n",
"s1 = 0.9572                                             // in Kj/Kg.k\n",
"h2s = 285.58                                            // in kj/kg\n",
"// Calculations\n",
"wcvdot = -(mdot*(h2-h1))\n",
"eta = (h2s-h1)/(h2-h1)        \n",
"// Results\n",
"printf( ' The power in  is %f kw',wcvdot);\n",
"printf( ' The isentropic efficiency is %.3f',eta)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.15: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 1.00                               // pressure of entering air in bar\n",
"T1 = 293.00                             // temperature of entering air in kelvin\n",
"P2 = 5.00                               // pressure of exit air in bar\n",
"n = 1.3\n",
"R = 8.314/28.97\n",
"// From table A-22\n",
"h1 = 293.17                             // in kj/kg\n",
"h2 = 426.35                             //  in kj/kg\n",
"// Calculations\n",
"T2 = T1*((P2/P1)**((n-1)/n))             // in kelvin\n",
"wcvdot=((n*R)/(n-1))*(T1-T2)            // in kj/kg\n",
"Qcvdot= wcvdot + (h2-h1)                // in kj/kg\n",
"// Results\n",
"printf( ' The work per unit mass passing through the device is %.2f kJ/kg',wcvdot)\n",
"printf( ' The heat transfer per unit mass is %.2f kJ/kg. ',Qcvdot)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.1: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"T = 373.15                                // temperature in kelvin\n",
"// From table A-2\n",
"p = 1.014*(10**5)                         // pressure in pascal\n",
"vg = 1.673\n",
"vf = 1.0435e-3\n",
"sg = 7.3549\n",
"sf = 1.3069\n",
"// Calculations\n",
"w = p*(vg-vf)*(10**(-3))\n",
"Q = T*(sg-sf)\n",
"// Results \n",
"printf( ' The work per unit mass is %.3f KJ/Kg',w)\n",
"printf( ' The heat transfer per unit mass is %.2f kj/kg',Q)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.2: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"// Assumptions:\n",
"// From table A-2 at 100 degree celcius\n",
"ug = 2506.5                                  // in kj/kg\n",
"uf = 418.94                                  // in kj/kg\n",
"sg = 7.3549\n",
"sf = 1.3069\n",
"// Calculations:-\n",
"// From energy balance\n",
"W = -(ug-uf)\n",
"// From entropy balance\n",
"sigmabym = (sg-sf)\n",
"// Results\n",
"printf( ' The net work per unit mass is %.2f KJ/kg. ',W)\n",
"printf( ' The amount of entropy produced per unit mass is %.2f KJ/kg.',sigmabym)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.3: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"T1 = 273.0                                // initial temperature of saturated vapor in kelvin\n",
"P2 = 0.7*(10**6)                          // final pressure in pascal\n",
"// From table A-10,\n",
"u1 = 227.06                               // in kj/kg\n",
"// minimum theoretical work corresponds to state of isentropic compression\n",
"// From table A-12,\n",
"u2s = 244.32                              // in kj/kg\n",
" \n",
"// Calculations \n",
"Wmin = u2s-u1\n",
"// Results\n",
"printf( ' The minimum theoretical work input required per unit mass of refrigerant is: %.2f kJ/kg',Wmin)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.4: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given :-\n",
"Qdot = -1.2                          // in kilo watt\n",
"Tb = 300.0                           // in kelvin\n",
"Tf = 293.0                           // in kelvin\n",
"// Calculations\n",
"// Part (a)\n",
"// From entropy balance \n",
"sigmadot = -Qdot/Tb\n",
"// Part(b)\n",
"// From entropy balance \n",
"sigmadt = -Qdot/Tf\n",
"// Results\n",
"printf( ' The rate of entropy production with gearbox as system is %f kw/k',sigmadot)\n",
"printf( ' The rate of entropy production with gearbox + sorrounding as system is %f kw/k',sigmadt)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.5: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// GIven:-\n",
"Tmi = 1200.0                                   // initial temperature of metal in kelvin\n",
"cm = 0.42                                      // specific heat of metal in KJ/kg.k\n",
"mm = 0.3                                       // mass of metal in kg\n",
"Twi = 300.0                                    // initial temperature of water in kelvin\n",
"cw = 4.2                                       // specific heat of water in KJ/Kg.k\n",
"mw = 9.0                                       // mass of water in kg\n",
"// Calculations\n",
"// Part(a)\n",
"// Solving energy balance equation yields\n",
"Tf = (mw*(cw/cm)*Twi+mm*Tmi)/(mw*(cw/cm)+mm)\n",
"// Part (b)\n",
"// Solving entropy balance equation yields\n",
"sigma = mw*cw*log(Tf/Twi)+mm*cm*log(Tf/Tmi)\n",
"// Results\n",
"printf( ' The final equilibrium temperature of the metal bar and the water is %.2f kelvin.',Tf)\n",
"printf( ' The amount of entropy produced is: %.2f kJ/k.',sigma)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.6: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 30.0                                            // pressure of steam entering the turbine in bar\n",
"T1 = 400.0                                           // temperature of steam entering the turbine in degree celcius\n",
"V1 = 160.0                                           // velocity of steam entering the turbine in m/s\n",
"T2 = 100.0                                           // temperature of steam exiting in degree celcius\n",
"V2 = 100.0                                           // velocity of steam exiting in m/s\n",
"Wcvdot = 540.0                                       // work produced by turbine in kJ/kg of steam\n",
"Tb = 350.0                                           // temperature of the boundary in kelvin\n",
"// From table A-4 and table A-2\n",
"h1 = 3230.9                                          // specific enthalpy at entry in Kj/kg\n",
"h2 = 2676.1                                          // specific enthalpy at exit in kj/kg\n",
"// Calculations\n",
"// Reduction in mass and energy balance equations results in \n",
"Qcvdot = Wcvdot + (h2 - h1)+ (V2**2-V1**2)/(2*(10**3))  // heat transfer rate\n",
"// From table A-2\n",
"s2 = 7.3549                                             // in kj/kg.k\n",
"// From table A-4\n",
"s1 = 6.9212                                             // in kj/kg.k\n",
"// From entropy and mass balance equations\n",
"sigmadot = -(Qcvdot/Tb) + (s2-s1)\n",
"// Results\n",
"printf( 'The rate at which entropy is produced within the turbine per kg of steam  flowing is %.2f kJ/kg.k',sigmadot)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.7: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"T1 = 294.0                            // entry temperature of air in kelvin\n",
"P1 = 5.1                              // entry pressure of air in bars\n",
"T2 = 352.0                            // exit temperature of hot stream in kelvin\n",
"P2 = 1.0                              // exit pressure of hot stream in bars\n",
"T3 = 255.0                            // exit temperature of cold stream in kelvin\n",
"P3 = 1.0                              // exit pressure of cold stream in bars\n",
"cp = 1.0                              // in kj/kg.k\n",
"// Calculations\n",
"R = 8.314/28.97\n",
"se = 0.4*(cp*log((T2)/(T1))-R*log(P2/P1)) + 0.6*(cp*log((T3)/(T1))-R*log(P3/P1))\n",
"                                      // specific entropy in kj/kg.k\n",
"// Results\n",
"printf( ' Specific entropy in kj/kg.k =  %.3f KJ/kg.',se)\n",
"printf( ' Since se > 0, the claim of the writer is true');"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.8: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 3.5                                          // pressure of refrigerant entering the compressor in bars\n",
"T1 = 268.0                                        // temperature of refrigerant entering the compressor in kelvin\n",
"P2 = 14.0                                         // pressure of refrigerant entering the condenser in bars\n",
"T2 = 348.0                                        // temperature of refrigerant entering the condenser in kelvin\n",
"P3 = 14.0                                         // pressure of refrigerant exiting the condenser in bars\n",
"T3 = 301.0                                        // temperature of refrigerant exiting the condenser in kelvin\n",
"P4 = 3.5                                          // pressure of refrigerant after passing through expansion valve in bars\n",
"P5 = 1.0                                          // pressure of indoor return air entering the condenser in bars\n",
"T5 = 293.0                                        // temperature of indoor return air entering the condenser in kelvin\n",
"AV5 = 0.42                                        // volumetric flow rate of indoor return air entering the condenser in m^3/s\n",
"P6 =  1.0                                         // pressure of return air exiting the condenser in bar\n",
"T6 = 323.0                                        // temperature of return air exiting the condenser in kelvin\n",
"// Part(a)\n",
"// From table A-9\n",
"s1 = 0.9572                                       // in kj/kg.k\n",
"// Interpolating in table A-9\n",
"s2 = 0.98225                                      // in kj/kg.k\n",
"h2 = 294.17                                       // in kj/kg\n",
"// From table A-7\n",
"s3 = 0.2936                                       // in kj/kg.k\n",
"h3 = 79.05                                        // in kj/kg\n",
"h4 = h3                                           // since expansion through valve is throttling process\n",
"// From table A-8\n",
"hf4 = 33.09                                       // in kj/kg\n",
"hg4 = 246.00                                      // in kj/kg\n",
"sf4 = 0.1328                                      // in kj/kg.k\n",
"sg4 = 0.9431                                      // in kj/kg.k\n",
"cp = 1.005                                        // in kj/kg.k\n",
"// Calculations\n",
"x4 = (h4-hf4)/(hg4-hf4)                           // quality at state 4\n",
"s4 = sf4 + x4*(sg4-sf4)                           // specific entropy at state 4\n",
"// CONDENSER!!\n",
"v5 = ((8314/28.97)*T5)/(P5*(10**5))               // specific volume at state 5\n",
"mairdot = AV5/v5                            \n",
"h6 = cp*T6\n",
"h5 = cp*T5\n",
"mrefdot = mairdot*(h6-h5)/(h2-h3)\n",
"deltaS65 = cp*log(T6/T5)-(8.314/28.97)*log(P6/P5) // change in specific entropy\n",
"sigmacond = (mrefdot*(s3-s2)) + (mairdot*(deltaS65))\n",
"// COMPRESSOR!!\n",
"sigmacomp = mrefdot*(s2-s1)\n",
"// VALVE!!\n",
"sigmavalve = mrefdot *(s4-s3)\n",
"// Results\n",
"printf( ' The rates of entropy production for control volume enclosing the condenser  is %f kw/k',sigmacond);\n",
"printf( ' The rates of entropy production for control volume enclosing the compressor  is %f kW/K.',sigmacomp);\n",
"printf( ' The rates of entropy production for control volume enclosing the expansion valve  is %f kW/K ',sigmavalve)"
   ]
   }
,
{
		   "cell_type": "markdown",
		   "metadata": {},
		   "source": [
			"## Example 6.9: Example.sce"
		   ]
		  },
  {
"cell_type": "code",
	   "execution_count": null,
	   "metadata": {
	    "collapsed": true
	   },
	   "outputs": [],
"source": [
"// Given:-\n",
"P1 = 1.00                                    // initial pressure in bar\n",
"T1 = 300.00                                  // initial temperature in kelvin\n",
"T2 = 650.00                                  // final temperature in kelvin\n",
"// Part(a)\n",
"// From table A-22\n",
"pr2 = 21.86                               \n",
"pr1 = 1.3860\n",
"k = 1.39                                     // From table A-20\n",
"// Calculations\n",
"p2 = P1*(pr2/pr1)\n",
"p2a = P1*((T2/T1)**(k/(k-1)))\n",
"// Results\n",
"printf( ' P2  =  %f bar.',p2)\n",
"printf( ' Part(b) IT software problem');\n",
"printf( ' P2a  = %f bar',p2a);"
   ]
   }
],
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		  "kernelspec": {
		   "display_name": "Scilab",
		   "language": "scilab",
		   "name": "scilab"
		  },
		  "language_info": {
		   "file_extension": ".sce",
		   "help_links": [
			{
			 "text": "MetaKernel Magics",
			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
			}
		   ],
		   "mimetype": "text/x-octave",
		   "name": "scilab",
		   "version": "0.7.1"
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		 "nbformat_minor": 0
}