{ "metadata": { "name": "", "signature": "sha256:fa4aed71f1066121dfd73577f913169c9d8ae9a618e0c3fdc846fc1c3ef047bd" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter6-Wind Energy" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.2.1-pg244" ] }, { "cell_type": "code", "collapsed": false, "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": {} } ] }