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diff --git a/Fundamental_of_internal_combustion_engines/chap16.ipynb b/Fundamental_of_internal_combustion_engines/chap16.ipynb new file mode 100755 index 00000000..158b33df --- /dev/null +++ b/Fundamental_of_internal_combustion_engines/chap16.ipynb @@ -0,0 +1,874 @@ +{
+ "metadata": {
+ "name": ""
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+ {
+ "cells": [
+ {
+ "cell_type": "heading",
+ "level": 1,
+ "metadata": {},
+ "source": [
+ "Chapter16:Engine Testing and Performance"
+ ]
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.1 page no: 519"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "N=3000 #The speed of the engine in rpm \n",
+ "r=9 #Compression ratio \n",
+ "l=17.2 #The length of the connecting rod in cm\n",
+ "t=20 #The combustion ends at a TDC in degrees\n",
+ "k=3 #Three litre spark engine\n",
+ "n=6.0 #V-6 Engine\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "Vs=(k/n)*10**-3\n",
+ "d=(((Vs*4)/math.pi)**(1/3.0))\n",
+ "L=d*100\n",
+ "up=2*d*N/60.0\n",
+ "Vc=(Vs/(r-1))*10**6\n",
+ "cr=L/2.0\n",
+ "R=l/cr\n",
+ "up1=up*((math.pi/2.0)*math.sin(math.pi/9.0)*(1+(math.cos(math.pi/9.0)/(R**2-(math.sin(math.pi/9.0)**2))**(1/2.0))))\n",
+ "s=(cr*math.cos(math.pi/9.0))+(l**2-(cr**2)*(math.sin(math.pi/9.0))**2)**(1/2.0)\n",
+ "x=l+cr-s\n",
+ "V=Vc+(math.pi/4.0)*(d*100)**2*x\n",
+ "\n",
+ "#Output \n",
+ "print\"(a)The cylinder bore and The stroke length (d = L) = \",round(L,2),\"cm\"\n",
+ "print\"(b) The average piston speed = \",round(up,2),\"m/s\"\n",
+ "print\"(c) The clearence volume of one cylinder = \",round(Vc,2),\"cm**3\"\n",
+ "print\"(d) The piston speed at the end of combustion = \",round(up1,2),\"m/s\"\n",
+ "print\"(e) The distance the piston travels from TDC at the end of combustion = \",round(x,2),\"cm\" \n",
+ "print\"(f) Instantaneous volume = \",round(V,2),\"cm**3\" \n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "(a)The cylinder bore and The stroke length (d = L) = 8.6 cm\n",
+ "(b) The average piston speed = 8.6 m/s\n",
+ "(c) The clearence volume of one cylinder = 62.5 cm**3\n",
+ "(d) The piston speed at the end of combustion = 5.71 m/s\n",
+ "(e) The distance the piston travels from TDC at the end of combustion = 0.32 cm\n",
+ "(f) Instantaneous volume = 81.24 cm**3\n"
+ ]
+ }
+ ],
+ "prompt_number": 12
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.2 page no: 521"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#Input data\n",
+ "d=0.175 #The diameter of the bore in m\n",
+ "L=0.32 #The length of the stroke in m\n",
+ "p=6.5 #Mean effective pressure in bar\n",
+ "pp=0.4 #Pumping loop mean effective pressure in bar\n",
+ "N=510.0 #The speed of the engine in rpm\n",
+ "pm=0.65 #Diagrams from the dead cycle give a mep in bar\n",
+ "n=55.0 #Firing strokes per minute \n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "pmi=p-pp \n",
+ "c=((N/2.0)-n) \n",
+ "ipw=pmi*10**5*L*(math.pi/4.0)*d**2*(n/60.0)*(1/1000.0) \n",
+ "Pp=pm*10**5*L*(math.pi/4.0)*d**2*(c/60.0)*(1/1000.0) \n",
+ "fp=ipw-Pp #Power in kW\n",
+ "fip=pmi*10**5*L*(math.pi/4.0)*d**2*(N/(2*60))*(1/1000.0)\n",
+ "fbp=fip-fp\n",
+ "nm=(fbp/fip)*100\n",
+ "\n",
+ "#Output \n",
+ "print\" The full load break power = \",round(fbp,2),\"kW\" \n",
+ "print\"The mechanical efficiency of the engine = \",round(nm,2),\"percent\"\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ " The full load break power = 17.32 kW\n",
+ "The mechanical efficiency of the engine = 86.79 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 7
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.3 page no: 522"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "d=0.09 #The diameter of the bore in m\n",
+ "L=0.1 #The length of the stroke in m\n",
+ "T=120 #The torque measured in Nm\n",
+ "n=4 #Number of cylinders \n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "pmb=((4*math.pi*T)/(L*(math.pi/4)*d**2*n))/10.0**5\n",
+ "\n",
+ "#Output \n",
+ "print\"The brake mean effective pressure = \",round(pmb,2),\"bar\"\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The brake mean effective pressure = 5.93 bar\n"
+ ]
+ }
+ ],
+ "prompt_number": 8
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.4 page no: 522"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#Input data\n",
+ "d=0.06 #The diameter of the bore in m \n",
+ "L=0.085 #The length of the stroke in m\n",
+ "N=3000 #The speed of the engine in rpm\n",
+ "r=0.35 #Torque arm radius in m\n",
+ "W=160 #Weight in N\n",
+ "f=6.6 #Fuel consumption in l/h\n",
+ "g=0.78 #specific gravity of the fuel \n",
+ "CV=44000 #The calorific value of the fuel in kJ/kg\n",
+ "w1=114 #Brake load for cylinder 1 in N\n",
+ "w2=110 #Brake load for cylinder 2 in N\n",
+ "w3=112 #Brake load for cylinder 3 in N\n",
+ "w4=116 #Brake load for cylinder 4 in N\n",
+ "n=4 #Number of cylinders\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "Vf=(f*10**-3)/3600.0\n",
+ "df=g*1000\n",
+ "mf=df*Vf\n",
+ "T=W*r\n",
+ "bp=(2*math.pi*N*T)/(60.0*1000.0)\n",
+ "pmb=((120*bp*1000)/(L*(math.pi/4.0)*d**2*N*n))/10.0**5\n",
+ "nb=((bp)/(mf*CV))*100\n",
+ "bsfc=(mf*3600)/bp\n",
+ "bp1=((2*math.pi*N*w1*r)/(60.0*1000.0))\n",
+ "ip1=bp-bp1 \n",
+ "ip2=bp-((2*math.pi*N*w2*r)/(60*1000))\n",
+ "ip3=bp-((2*math.pi*N*w3*r)/(60*1000))\n",
+ "ip4=bp-((2*math.pi*N*w4*r)/(60*1000))\n",
+ "ip=ip1+ip2+ip3+ip4\n",
+ "nm=(bp/ip)*100\n",
+ "pmi=pmb/(nm/100.0)\n",
+ "\n",
+ "#Output\n",
+ "print\"The brake power =\",round(bp,3),\"kW \" \n",
+ "print\"The brake mean effective pressure = \",round(pmb,3),\"bar\"\n",
+ "print\"The brake thermal efficiency =\" ,round(nb,0),\"percent\"\n",
+ "print\"The brake specific fuel consumption = \",round(bsfc,3),\"kg/kWh\"\n",
+ "print\"The indicated power = \",round(ip,2),\"kW \"\n",
+ "print\"The mechanical efficiency =\", round(nm,1),\"percent \" \n",
+ "print\"The indicated mean effective pressure = \",round(pmi,1),\"bar\" \n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The brake power = 17.593 kW \n",
+ "The brake mean effective pressure = 7.32 bar\n",
+ "The brake thermal efficiency = 28.0 percent\n",
+ "The brake specific fuel consumption = 0.293 kg/kWh\n",
+ "The indicated power = 20.67 kW \n",
+ "The mechanical efficiency = 85.1 percent \n",
+ "The indicated mean effective pressure = 8.6 bar\n"
+ ]
+ }
+ ],
+ "prompt_number": 1
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.5 page no: 523"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "d=0.15 #The diameter of the bore in m\n",
+ "L=0.16 #The length of the stroke in m\n",
+ "N=500 #The speed of the engine in rpm\n",
+ "mf=0.0475 #Fuel consumption in kg/min\n",
+ "CV=42000 #The calorific value in kJ/kg\n",
+ "w=400 #The tension on either side of the pulley in N\n",
+ "c=2.2 #Brake circumference in m\n",
+ "l=50 #Length of the indicator diagram in mm\n",
+ "ap=475 #Area of the positive loop of indicator diagram in mm**2\n",
+ "an=25 #Area of the negative loop of indicator diagram in mm**2\n",
+ "s=0.8333 #Spring constant in bar/mm\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "r=c/(2.0*math.pi)\n",
+ "T=w*r\n",
+ "bp=(2*math.pi*N*T)/(60.0*1000.0)\n",
+ "M=(ap-an)/l\n",
+ "imep=M*s\n",
+ "ip=(imep*10**5*L*(math.pi/4.0)*d**2*(N/(2.0*60.0))*(1/1000.0))\n",
+ "nm=(bp/ip)*100\n",
+ "nb=((bp*60)/(mf*CV))*100\n",
+ "ni=((nb/100.0)/(nm/100.0))*100\n",
+ "bsfc=(mf*60)/bp\n",
+ "\n",
+ "#Output\n",
+ "print\"(a) The brake power = \",round(bp,3),\"kW\"\n",
+ "print \"(b) The indicated power = \",round(ip,3),\"kW\"\n",
+ "print\"(c) The mechanical efficiency = \",round(nm,0),\"percent\"\n",
+ "print\"(d) The brake thermal efficiency = \",round(nb,3)\n",
+ "print\"(e) The indicated thermal efficiency = \",round(ni,3)\n",
+ "print\"(f) The brake specific fuel consumption = \",round(bsfc,3),\" kg/kWh\"\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "(a) The brake power = 7.333 kW\n",
+ "(b) The indicated power = 8.835 kW\n",
+ "(c) The mechanical efficiency = 83.0 percent\n",
+ "(d) The brake thermal efficiency = 22.055\n",
+ "(e) The indicated thermal efficiency = 26.573\n",
+ "(f) The brake specific fuel consumption = 0.389 kg/kWh\n"
+ ]
+ }
+ ],
+ "prompt_number": 2
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.6 page no: 524"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "n=8 #Number of cylinders\n",
+ "d=0.08 #The diameter of the bore in m\n",
+ "L=0.1 #The length of the stroke in m\n",
+ "N=4500 #The speed of the engine in rpm \n",
+ "dy=0.55 #The dynamometer readings in m\n",
+ "w=40 #The weight of the dynamometer scale reading in kg\n",
+ "c=100 #Fuel consumption in cc\n",
+ "t=9.5 #Time taken for fuel consumption in s\n",
+ "CV=44000 #The calorific value of the fuel in kJ/kg\n",
+ "p=1 #The atmospheric air pressure in bar\n",
+ "T=300 #The atmospheric air temperature in K\n",
+ "ma=6 #Mass flow rate of air in kg/min\n",
+ "g=0.7 #Specific gravity of the fuel \n",
+ "Vc=65 #The clearance volume of each cylinder in cc\n",
+ "R=287 #Real gas constant in J/kgK\n",
+ "g=1.4 #Isentropic index\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "bp=(2*math.pi*N*dy*w*9.81)/(60.0*1000.0)\n",
+ "bmep=((bp*1000*60)/(L*(math.pi/4.0)*d**2*(N/2.0)*n))/10.0**5\n",
+ "mf=(c*g*3600)/(t*2.0*1000.0)\n",
+ "bsfc=(mf/bp)\n",
+ "bsac=(ma*60)/bp\n",
+ "a=bsac/bsfc\n",
+ "nb=((bp*3600)/(mf*CV))*100\n",
+ "Va=(ma*R*T)/(p*10.0**5)\n",
+ "Vs=(math.pi/4.0)*d**2*L*(N/2.0)*n\n",
+ "nv=(Va/Vs)*100\n",
+ "Vs1=((math.pi/4.0)*d**2*L)*10**6\n",
+ "cr=(Vs1+Vc)/Vc\n",
+ "na=(1-(1/cr)**(g-1))*100\n",
+ "re=((nb)/(na))*100\n",
+ "\n",
+ "#Output\n",
+ "print\"The brake power = \",round(bp,1),\"kW\" \n",
+ "print\"The brake mean effective pressure = \",round(bmep,3),\"bar\"\n",
+ "print\"The brake specific fuel consumption = \",round(bsfc,3),\"kg/kWh\"\n",
+ "print\"The brake specific air consumption = \",round(bsac,3),\"kg/kWh\"\n",
+ "print\"The air fuel ratio = \",round(a,2)\n",
+ "print\"The brake thermal efficiency = \",round(nb,3),\"percent\" \n",
+ "print\"The volumetric efficiency = \",round(nv,1),\"percent\"\n",
+ "print\"The relative efficiency = \",round(re,1),\"percent\"\n",
+ "\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The brake power = 101.7 kW\n",
+ "The brake mean effective pressure = 6.744 bar\n",
+ "The brake specific fuel consumption = 0.261 kg/kWh\n",
+ "The brake specific air consumption = 3.54 kg/kWh\n",
+ "The air fuel ratio = 13.57\n",
+ "The brake thermal efficiency = 31.369 percent\n",
+ "The volumetric efficiency = 57.1 percent\n",
+ "The relative efficiency = 54.1 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 7
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.7 page no: 526"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "n=6 #Number of cylinders\n",
+ "Do=0.03 #Orifice diameter in m\n",
+ "Cd=0.6 #Coefficient of discharge \n",
+ "H=0.14 #Pressure drop across the orifice\n",
+ "d=0.1 #The diameter of the bore in m\n",
+ "L=0.11 #The length of the stroke in m\n",
+ "W=540 #Brake load in N\n",
+ "N=2500 #Engine speed in rpm\n",
+ "ch=83/17 #C/H ratio by mass\n",
+ "p=1 #Ambient pressure in bar\n",
+ "t=18 #Time taken for fuel consumption in s\n",
+ "f=100 #The amount of fuel consumption in cc\n",
+ "T=300.0 #Ambient air temperature in K\n",
+ "df=780 #The density of the fuel in kg/m**3\n",
+ "R=287.0 #Real gas constant in J/kgK\n",
+ "g=9.81 #Gravitational force constant in m/s**2\n",
+ "dhg=13600 #Density of Hg in kg/m**3\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "da=(p*10**5)/(R*T)\n",
+ "Va=(Cd*(math.pi/4.0)*Do**2*(2*g*H*(dhg/da))**(1/2.0))\n",
+ "Vs=(math.pi/4.0)*d**2*L*(N/(2.0*60.0))*n\n",
+ "nv=(Va/Vs)*100\n",
+ "bp=(W*N)/(20000.0)\n",
+ "bmep=((bp*1000)/(L*(math.pi/4.0)*d**2*(N/(2.0*60.0))*n))/10.0**5\n",
+ "T=(60*bp*1000)/(2.0*math.pi*N)\n",
+ "mf=(f/18.0)*(780/1000.0)*(1/1000.0)*3600\n",
+ "bsfc=mf/bp\n",
+ "so=(0.83*(32/12.0))+(0.17*(8/1.0))\n",
+ "sa=so/bsfc\n",
+ "maa=Va*da\n",
+ "af=(maa*3600)/mf\n",
+ "pea=((af-sa)/sa)*100\n",
+ "\n",
+ "#Output\n",
+ "print\"The volumetric efficiency = \",round(nv,3),\"percent\" \n",
+ "print\"The brake mean effective pressure = \",round(bmep,3),\"bar\" \n",
+ "print\"The brake power = \",bp,\"kW\" \n",
+ "print\"The Torque = \",round(T,3),\"Nm\"\n",
+ "print\"The brake specific fuel consumption = \",round(bsfc,3),\"kg/kWh\" \n",
+ "print\"The percentage of excess air = \",round(pea,1),\"percent\""
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The volumetric efficiency = 70.433 percent\n",
+ "The brake mean effective pressure = 6.25 bar\n",
+ "The brake power = 67.5 kW\n",
+ "The Torque = 257.831 Nm\n",
+ "The brake specific fuel consumption = 0.231 kg/kWh\n",
+ "The percentage of excess air = 31.9 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 12
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.8 page no: 528"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "d=0.2 #The diameter of bore in m\n",
+ "L=0.3 #The length of the stroke in m\n",
+ "r=5.5 #The compression ratio of the engine\n",
+ "N=400 #The speed of the engine in rpm\n",
+ "imep=4.5 #The indicative mean effective pressure in bar\n",
+ "a=6 #Air to gas by volume \n",
+ "CV=12000 #The calorific value of the gas in kJ/m**3\n",
+ "T=340 #The temperature at the beginning of the compression stroke in K\n",
+ "p=0.97 #The pressure at the beginning of the compression stroke in bar\n",
+ "g=1.4 #Adiabatic index\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "Vs=(math.pi/4.0)*d**2*L\n",
+ "Vc=Vs/(r-1)\n",
+ "V=Vs+Vc\n",
+ "Vg=V/7.0\n",
+ "Vntp=((p*Vg)/T)*(273/1.013)\n",
+ "Q=Vntp*CV*(N/(2.0*60.0))\n",
+ "ip=(imep*10**5*L*(math.pi/4.0)*d**2*(N/(2.0*60.0))*(1/1000.0))\n",
+ "ni=(ip/Q)*100\n",
+ "na=(1-(1/r)**(g-1))*100\n",
+ "nr=(ni/na)*100\n",
+ "\n",
+ "#Output\n",
+ "print\"The indicated power = \",round(ip,2),\"kW\" \n",
+ "print\"The thermal efficiency = \",round(ni,1),\"percent\" \n",
+ "print\"The relative efficiency = \",round(nr,1),\"percent\" \n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The indicated power = 14.14 kW\n",
+ "The thermal efficiency = 27.9 percent\n",
+ "The relative efficiency = 56.5 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 11
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.9 page no: 529"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "n=6.0 #Number of cylinder\n",
+ "bp=130.0 #Brake power in kW\n",
+ "N=1800.0 #The speed of the engine in rpm \n",
+ "CV=42000.0 #The calorific value of the fuel in kJ/kg\n",
+ "C=86.0 #The composition of carbon in the fuel in percent\n",
+ "H=13.0 #The composition of Hydrogen in the fuel in percent\n",
+ "NC=1.0 #The non combustibles present in the fuel in percent\n",
+ "na=85.0 #The absolute volumetric efficiency in percent\n",
+ "ni=38.0 #The indicated thermal efficiency in percent\n",
+ "nm=80.0 #The mechanical efficiency in percent\n",
+ "ac=110.0 #The excess consumption of air in percent\n",
+ "sb=1.2 #The stroke to the bore ratio \n",
+ "da=1.3 #The density of air in kg/m**3\n",
+ "\n",
+ "#Calculations \n",
+ "import math\n",
+ "saf=(((C/100.0)*(32/12.0))+((H/100.0)*(8/1.0)))*(1/0.23)\n",
+ "aaf=saf*(1+1.1)\n",
+ "Ma=(0.23*32)+(0.77*28)\n",
+ "a=(C/100)/12.0\n",
+ "b=(H/100.0)/2.0\n",
+ "x=aaf/Ma\n",
+ "c=(0.21*x)-a-(b/2.0)\n",
+ "d1=0.79*x\n",
+ "ip=bp/(nm/100.0)\n",
+ "mf=ip/((ni/100.0)*CV)\n",
+ "ma=mf*aaf\n",
+ "Va=ma/da\n",
+ "Vs=Va/(na/100.0)#The swept volume per second in m**3/s\n",
+ "d=((Vs*(4/math.pi)*(1/1.2)*((2*60)/N)*(1/n))**(1/3.0))*1000\n",
+ "L=1.2*d\n",
+ "T=a+c+d1\n",
+ "CO2=(a/T)*100\n",
+ "O2=(c/T)*100\n",
+ "N2=(d1/T)*100\n",
+ "\n",
+ "#Output\n",
+ "print\"The volumetric composition of dry exhaust gas :\" \n",
+ "print\"1) CO2 = \",round(a,2),\"kmol\",\"and\" \n",
+ "print\"volume = \",round(CO2,2),\"percent\" \n",
+ "print\"2) O2 = \",round(c,3),\"kmol\",\"and\" \n",
+ "print\"volume = \",round(O2,3),\"percent\"\n",
+ "print\"3) N2 = \",round(d1,3),\"kmol\",\"and\" \n",
+ "print\"volume = \",round(N2,3),\"percent\"\n",
+ "print\"The bore of the engine = \",round(d,0),\"mm\" \n",
+ "print\"The stroke of the engine = \",round(L,1),\"mm\""
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "The volumetric composition of dry exhaust gas :\n",
+ "1) CO2 = 0.07 kmol and\n",
+ "volume = 7.03 percent\n",
+ "2) O2 = 0.117 kmol and\n",
+ "volume = 11.456 percent\n",
+ "3) N2 = 0.831 kmol and\n",
+ "volume = 81.517 percent\n",
+ "The bore of the engine = 149.0 mm\n",
+ "The stroke of the engine = 178.8 mm\n"
+ ]
+ }
+ ],
+ "prompt_number": 13
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.10 page no: 531"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "d=0.18 #The diameter of the cylinder in m\n",
+ "L=0.24 #The length of the stroke in m\n",
+ "t=30.0 #Duration trail in min \n",
+ "N=9000.0 #Number of revolutions \n",
+ "Ne=4450.0 #Total number of explosions\n",
+ "pmi=5.35 #Gross imep in bar\n",
+ "pp=0.35 #Pumping imep in bar\n",
+ "W=40.0 #Net load on brake wheel in kg\n",
+ "dd=0.96 #Diameter of the brake wheel drum in m\n",
+ "dr=0.04 #Diameter of the rope in m\n",
+ "V=2.6 #Volume of gas used in m**3\n",
+ "pg=136.0 #pressure of gas in mmof Hg\n",
+ "dg=0.655 #The density of gas in kg/m**3\n",
+ "T=290.0 #The ambient temperature of air in K\n",
+ "CV=19000.0 #The calorific value of the fuel in kJ/m**3\n",
+ "ta=40.0 #Total air used in m**3\n",
+ "p=720.0 #Pressure of air in mm of Hg\n",
+ "Te=340.0 #Temperature of exhaust gas in degree centigrade \n",
+ "Cpg=1.1 #Specific heat of gas in kJ/kgK\n",
+ "C=80.0 #Cooling water circulated in kg\n",
+ "Tr=30.0 #Rise in temperature of cooling water in degree centigrade \n",
+ "R=287.0 #Real gas constant in J/kgK\n",
+ "\n",
+ "#Calculations\n",
+ "#import math\n",
+ "ip=(pmi-pp)*10**5*L*(math.pi/4.0)*d**2*(Ne/(30.0*60.0))*(1/1000.0)\n",
+ "bp=(math.pi*(N/(30.0*60.0))*W*9.81*(dd+dr)*(1/1000.0))\n",
+ "pgs=760+(pg/13.6)\n",
+ "Vg=((pgs*V)/290.0)*(273/760.0)\n",
+ "Q=(Vg*CV)/30.0\n",
+ "Qbp=bp*60\n",
+ "Qc=(C/t)*4.18*Tr\n",
+ "Va=(((p*ta)/T)*(273/760.0))/30.0\n",
+ "da=(1.013*10**5)/(R*273)\n",
+ "ma=Va*da\n",
+ "mg=(Vg/30)*dg\n",
+ "me=ma+mg\n",
+ "Qe=me*Cpg*(Te-(T-273))\n",
+ "Qu=Q-(Qe+Qc+Qbp)\n",
+ "nm=(bp/ip)*100\n",
+ "ni=((ip*60)/Q)*100 \n",
+ "x=((Qbp/1571.0)*100)\n",
+ "y=((Qc/1571.0)*100)\n",
+ "z=((Qe/1571.0)*100)\n",
+ "k=((Qu/1571.0)*100)\n",
+ "Qf=Qbp+Qc+Qe+Qu\n",
+ "\n",
+ "#Output\n",
+ "print Qe\n",
+ "print\" HEAT BALANCE SEAT\"\n",
+ "\n",
+ "print \" \\nHeat input kj/min % heat expenditure Kj/min %\"\n",
+ "print\"--------------------------------------------------------------------------------------------------\"\n",
+ "print\"heat supplied by fuel \",round(Q,0),\" 100 (a)Heat in bp \", round(Qbp,1),\" \",round(x,1)\n",
+ "print\" (b)Heat loss to cooling tower \",round(Qc,0),\" \",round(y,1)\n",
+ "print\" (c) Heat to exhaust gases \",round(Qe,0),\" \",round(z,0)\n",
+ "print\" (d)unaccounted losses \",round(Qu,0),\" \",round(k,1)\n",
+ "print\"Total \",round(Q,0),\" 100 total \",round(Qf,0), \" 100.0\"\n",
+ " \n",
+ "print\"\\nMechanical efficiency is\",round(nm,2),\"percent\"\n",
+ "print\"Thermal efficiency is\",round(ni,1),\"percent\"\n",
+ "\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ "565.475307496\n",
+ " HEAT BALANCE SEAT\n",
+ " \n",
+ "Heat input kj/min % heat expenditure Kj/min %\n",
+ "--------------------------------------------------------------------------------------------------\n",
+ "heat supplied by fuel 1571.0 100 (a)Heat in bp 369.8 23.5\n",
+ " (b)Heat loss to cooling tower 334.0 21.3\n",
+ " (c) Heat to exhaust gases 565.0 36.0\n",
+ " (d)unaccounted losses 301.0 19.1\n",
+ "Total 1571.0 100 total 1571.0 100.0\n",
+ "\n",
+ "Mechanical efficiency is 81.65 percent\n",
+ "Thermal efficiency is 28.8 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 20
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.11 page no: 533"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given \n",
+ "bp=30 #The brake power in kw\n",
+ "mf=10 #Mass flow rate of fuel in kg/h\n",
+ "CV=42000 #Calorific value of the fuel in kJ/kg\n",
+ "mw=9 #Mass flow rate of water in kg/min\n",
+ "Tr=60 #Rise in temperature of the cooling water in degree centigrade\n",
+ "mwe=9.5 #Mass flow rate of water through exhaust gas calorimeter in kg/min\n",
+ "Tc=40 #Rise in temperature when passing through calorimeter in degree centigrade\n",
+ "Te=80 #Temperature of exhaust gas leaving the calorimeter in degree centigrade\n",
+ "a=20 #Air fuel ratio\n",
+ "T=17 #Ambient temperature in degree centigrade\n",
+ "Cpw=4.18 #Specific heat of water in kJ/kgK\n",
+ "Cpg=1 #Mean specific heat of gas in kJ/kgK\n",
+ "\n",
+ "#Calculations\n",
+ "Qf=(mf/60.0)*CV \n",
+ "Qbp=bp*60\n",
+ "Qc=mw*Cpw*Tr\n",
+ "mg=(mf/60.0)+(mf/60.0)*a\n",
+ "Qe=(mwe*Cpw*Tc)+(mg*Cpg*(Te-T))\n",
+ "Qu=Qf-(Qbp+Qc+Qe)\n",
+ "x=((Qbp/Qf))*100\n",
+ "y=(Qc/Qf)*100\n",
+ "z=(Qe/Qf)*100\n",
+ "k=(Qu/Qf)*100\n",
+ "\n",
+ "#Output\n",
+ "print\" HEAT BALANCE SEAT\"\n",
+ "print \"\\n Heat input kj/min % heat expenditure Kj/min %\"\n",
+ "print\"--------------------------------------------------------------------------------------------------\"\n",
+ "print\"heat supplied by fuel \",Qf,\" 100 (a)Heat in bp \", Qbp,\" \",round(x,0)\n",
+ "print\" (b)Heat loss to cooling tower \",round(Qc,0),\" \",round(y,0)\n",
+ "print\" (c) Heat to exhaust gases \",round(Qe,0),\" \",round(z,0)\n",
+ "print\" (d)unaccounted losses \",round(Qu,0),\" \",round(k,0)\n",
+ "print\"Total \",Qf,\" 100 total \",Qf, \" 100\"\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ " HEAT BALANCE SEAT\n",
+ "\n",
+ " Heat input kj/min % heat expenditure Kj/min %\n",
+ "--------------------------------------------------------------------------------------------------\n",
+ "heat supplied by fuel 7000.0 100 (a)Heat in bp 1800 26.0\n",
+ " (b)Heat loss to cooling tower 2257.0 32.0\n",
+ " (c) Heat to exhaust gases 1809.0 26.0\n",
+ " (d)unaccounted losses 1134.0 16.0\n",
+ "Total 7000.0 100 total 7000.0 100\n"
+ ]
+ }
+ ],
+ "prompt_number": 85
+ },
+ {
+ "cell_type": "heading",
+ "level": 2,
+ "metadata": {},
+ "source": [
+ "Example 16.12 page no: 534"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "collapsed": false,
+ "input": [
+ "#given\n",
+ "n=4.0 #Number of cylinders\n",
+ "d=0.085 #The diameter of the bore m\n",
+ "L=0.095 #The length of the stroke in m\n",
+ "tr=0.35 #Torque radius in m\n",
+ "N=3000.0 #The speed of the engine in rpm\n",
+ "w=430.0 #Net brake load in N\n",
+ "w1=300.0 #Net brake load produced at the same speed by three cylinders in N\n",
+ "mf=0.24 #The mass flow rate of fuel in kg/min\n",
+ "CV=44000.0 #The calorific value of the fuel in kJ/kg\n",
+ "mw=65.0 #Mass flow rate of water in kg/min\n",
+ "Tw=12.0 #The rise in temperature in degree centigrade\n",
+ "a=15.0 #The air fuel ratio \n",
+ "Te=450.0 #The temperature of the exhaust gas in degree centigrade \n",
+ "Ta=17.0 #Ambient temperature in degree centigrade\n",
+ "p=76.0 #Barometric pressure in cm of Hg\n",
+ "H=15.5 #The proportion of hydrogen by mass in the fuel in percent\n",
+ "Cpe=1.0 #The mean specific heat of dry exhaust gas in kJ/kgK\n",
+ "Cps=2.0 #The specific heat of super heated steam in kJ/kgK\n",
+ "Cpw=4.18 #The specific heat of water in kJ/kgK\n",
+ "Ts=100.0 #At 76 cm of Hg The temperature in degree centigrade \n",
+ "hfg=2257 #The Enthalpy in kJ/kg\n",
+ "R=287.0 #Real gas cons tant in J/kgK\n",
+ "\n",
+ "#Calculations\n",
+ "import math\n",
+ "bp=(2*math.pi*N*w*tr)/(60.0*1000.0)\n",
+ "bp1=(2*math.pi*N*w1*0.35)/(60.0*1000.0)\n",
+ "ip=bp-bp1\n",
+ "ip1=n*ip\n",
+ "imep=((ip1*60*1000)/(L*(math.pi/4.0)*d**2*(N/2.0)*n))/10.0**5\n",
+ "ni=((ip1*60)/(mf*CV))*100\n",
+ "bsfc=(mf*60)/bp\n",
+ "Vs=(math.pi/4.0)*d**2*L*(N/2.0)*n\n",
+ "ma=a*mf\n",
+ "da=(1*10**5)/(R*(Ta+273))\n",
+ "Va=ma/da\n",
+ "nv=(Va/Vs)*100\n",
+ "Qf=mf*CV\n",
+ "Qbp=bp*60\n",
+ "Qc=mw*Cpw*Tw\n",
+ "mv=9*(H/100.0)*mf\n",
+ "me=ma+mf-mv\n",
+ "Qe=me*Cpe*(Te-Ta)\n",
+ "Qs=(mv*((Cpw*(Ts-Ta))+hfg+(Cps*(Te-Ts))))\n",
+ "Qu=Qf-(Qbp+Qc+Qe+Qs)\n",
+ "x=(Qbp/Qf)*100\n",
+ "y=(Qc/Qf)*100\n",
+ "z=(Qe/Qf)*100\n",
+ "k=(Qs/Qf)*100\n",
+ "l=(Qu/Qf)*100 \n",
+ "\n",
+ "#Output\n",
+ "print\" HEAT BALANCE SEAT\"\n",
+ "print \" Heat input kj/min % heat expenditure Kj/min %\"\n",
+ "print\"----------------------------------------------------------------------------------------------------\"\n",
+ "print\"heat supplied by fuel \",Qf,\" 100 (a)Heat in bp \", Qbp,\" \",round(x,2)\n",
+ "print\" (b)Heat loss to cooling tower \",round(Qc,0),\" \",round(y,2)\n",
+ "print\" (c) Heat to dry exhaust gases \",round(Qe,0),\" \",round(z,1)\n",
+ "print\" (d)Heat loss in steam \",round(Qs,0),\" \",round(k,1)\n",
+ "print\" (e)unaccounted losses \",round(Qu,0),\" \",round(l,2)\n",
+ "print\"Total \",Qf,\" 100 total \",Qf, \" 100\"\n",
+ "\n",
+ "print\"\\nimpep \",round(imep,2),\"bar\"\n",
+ "print\"Thermal efficiency \",round(ni,1),\"percent\"\n",
+ "print\"bsfc=\",round(bsfc,4),\"kg/kwh\"\n",
+ "print\"Volumetric efficiency=\",round(nv,1),\"percent\"\n"
+ ],
+ "language": "python",
+ "metadata": {},
+ "outputs": [
+ {
+ "output_type": "stream",
+ "stream": "stdout",
+ "text": [
+ " HEAT BALANCE SEAT\n",
+ " Heat input kj/min % heat expenditure Kj/min %\n",
+ "----------------------------------------------------------------------------------------------------\n",
+ "heat supplied by fuel 10560.0 100 (a)Heat in bp 2836.85816619 26.86\n",
+ " (b)Heat loss to cooling tower 3260.0 30.87\n",
+ " (c) Heat to dry exhaust gases 1518.0 14.4\n",
+ " (d)Heat loss in steam 1106.0 10.5\n",
+ " (e)unaccounted losses 1839.0 17.41\n",
+ "Total 10560.0 100 total 10560.0 100\n",
+ "\n",
+ "impep 10.61 bar\n",
+ "Thermal efficiency 32.5 percent\n",
+ "bsfc= 0.3046 kg/kwh\n",
+ "Volumetric efficiency= 92.6 percent\n"
+ ]
+ }
+ ],
+ "prompt_number": 21
+ }
+ ],
+ "metadata": {}
+ }
+ ]
+}
\ No newline at end of file |