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"cell_type": "heading",
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"metadata": {},
"source": [
"Chapter6-Wind Energy"
]
},
{
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"level": 2,
"metadata": {},
"source": [
"Example 6.2.1-pg244"
]
},
{
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"input": [
"##Ex.6.2.1. \n",
"import math\n",
"##For air,the value of gas constant\n",
"R=0.287 ##unit=kj/kg K\n",
"##T=15. in degreecalcius\n",
"T=15.+273.;##in kalvin\n",
"RT=0.287*10**3*288.;\n",
"P=1.01325*10**5;##unit=Pa;at 1 atm\n",
"Vi=15.;##unit=m/s\n",
"gc=1.;\n",
"D=120.;##turbine diameter;unit=m\n",
"N=40./60.;\n",
"##Air density\n",
"p=(P/RT);\n",
"print'%s %.2f %s'%(\"Air density p=\",p,\" kg/M^3\");\n",
"##1] Total_power= Ptotal=p*A*Vi^3/2*gc\n",
"##power density =Ptotal/A=p*Vi^3/2*gc\n",
"power_density=(1./(2.*gc))*(p*Vi**3.);\n",
"##2] Maximum_power_density=Pmax/A=8*p*Vi^3/27*gc\n",
"Maximum_power_density=(8./(27.*gc))*(p*Vi**3);\n",
"print'%s %.2f %s %.2f %s '%(\"\\n power density =Ptotal/A= \",power_density,\" W/m^2\"and \" \\n Maximum power density=Pmax/A= \",Maximum_power_density,\" W/m^2\");\n",
"##3]Assuming n=35%\n",
"n=0.35;\n",
"##let P/A=x\n",
"x=n*(power_density);\n",
"print'%s %.2f %s'%(\"\\n P/A=\",x,\" W/m^2\");\n",
"##4]Total power P= power density * Area\n",
"Total_power_P=724.*(math.pi/4.)*(D**2) ##Total power P= power density*(%pi/4)*D^2\n",
"print'%s %.2f %s %.2f %s'%(\"\\n Total_power_P=\",Total_power_P,\" watt\"and \"=\",Total_power_P*10**-3,\" kW\")\n",
"##5]Torgue at maximum efficiency\n",
"Tmax=(2./(27.*gc))*((1.226*D*Vi*Vi*Vi)/N);##Tmax=(2/(27*gc))*((p*D*Vi*Vi*Vi)/N);\n",
"print'%s %.2f %s'%(\"\\n Torgue at maximum efficiency=\",Tmax,\" Newton\")\n",
"##and maximum axial thurst\n",
"Fxmax=(3.14/(9.*gc))*1.226*D**2.*Vi**2.;##Fxmax=(%pi/(9*gc))*p*D^2*Vi^2;\n",
"print'%s %.2f %s'%(\"\\n maximum axial thurst=\",Fxmax,\" Newton\");\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Air density p= 1.23 kg/M^3\n",
"\n",
" power density =Ptotal/A= 2068.65 \n",
" Maximum power density=Pmax/A= 1225.86 W/m^2 \n",
"\n",
" P/A= 724.03 W/m^2\n",
"\n",
" Total_power_P= 8188247.09 = 8188.25 kW\n",
"\n",
" Torgue at maximum efficiency= 55170.00 Newton\n",
"\n",
" maximum axial thurst= 1385870.40 Newton\n"
]
}
],
"prompt_number": 5
}
],
"metadata": {}
}
]
}
|
