{ "metadata": { "name": "", "signature": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 3, Constructional Mechanical Features of line" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.1 : page 70" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from numpy import sqrt\n", "#Given Data :\n", "m=1/10 #unitless\n", "EL=66 #in KV\n", "E=EL/sqrt(3) #in KV\n", "#Formula : E=E1+(11/10)*E1+(131/100)*E1+(1651/1000)*E1=(5061/1000)*E1\n", "E1=E*(1000/5061) #in KV\n", "print \"E1 = %0.2f KV\" %E1 \n", "E2=E1*(11/10) #in KV\n", "print \"E2 = %0.3f KV\" %E2\n", "E3=E1*(131/100) #in KV\n", "print \"E3 = %0.2f KV\" %E3\n", "E4=E1*(1651/1000) #in KV\n", "print \"E4 = %0.2f KV\" %E4\n", "Eta=(E/(4*E4))*100 #in %\n", "print \"String Efficiency = %0.1f %%\" %Eta" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "E1 = 7.53 KV\n", "E2 = 8.282 KV\n", "E3 = 9.86 KV\n", "E4 = 12.43 KV\n", "String Efficiency = 76.6 %\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.2 : page 71" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from numpy import sqrt\n", "#Given Data :\n", "W=0.85 #in Kg/meter\n", "L=250 #in meter\n", "Ww=1.4 #in Kg\n", "SafetyFactor=5 #unitless\n", "UTS=10128 #Ultimate tensile strength in Kg\n", "T=UTS/SafetyFactor #in Kg\n", "Wi=0 #there is no ice\n", "Wr=sqrt((W+Wi)**2+Ww**2) #in Kg\n", "S=Wr*L**2/(8*T) #in meter\n", "Sv=(W/Wr)*S #in meter\n", "print \"Horizontal sag = %0.3f m\" %S\n", "print \"Vertical sag = %0.3f m\" %Sv " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Horizontal sag = 6.317 m\n", "Vertical sag = 3.278 m\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.3 : page 72" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from numpy import sqrt\n", "#Given Data :\n", "L=150 #in meter\n", "A=2 #in cm**2(cross sectional area)\n", "US=5000 #in Kg/cm**2(ultimate strength)\n", "g=8.9 #specific gravity\n", "Ww=1.5 #in Kg/m(wind pressure)\n", "SafetyFactor=5 #unitless\n", "B_strength=2*US #in Kg\n", "T=B_strength/SafetyFactor #in Kg\n", "Volume=A*100 #in cm**2\n", "Wc=1.78 #in Kg/m\n", "Wr=sqrt(Wc**2+Ww**2) #in Kg\n", "Sag=Wr*L**2/(8*T) #in meter\n", "print \"Sag = %0.2f m\" % Sag " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Sag = 3.27 m\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.4 : page 73" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from numpy import sqrt, pi\n", "#Given Data :\n", "L=160 #in meter\n", "d=0.95 #in cm\n", "A=pi*d**2/4 #in cm**2(cross sectional area)\n", "US=4250 #in Kg/cm**2(ultimate strength)\n", "g=8.9 #specific gravity\n", "Ww=1.5 #in Kg/m(wind pressure)\n", "SafetyFactor=5 #unitless\n", "B_strength=2*US #in Kg\n", "T=B_strength/SafetyFactor #in Kg\n", "Volume=A*100 #in cm**2\n", "Wc=1.78 #in Kg/m\n", "Wr=sqrt(Wc**2+Ww**2) #in Kg\n", "Sag=Wr*L**2/(8*T) #in meter\n", "print \"Sag = %.f m\" % Sag \n", "#Note : Answer in the book is not accurate." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Sag = 4 m\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.5 : page 73" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "#Given Data :\n", "m=75-45 #in meter\n", "L=300 #in meter\n", "T=2500 #in Kg\n", "w=0.9 #in kg/meter\n", "x=L/2-T*m/(w*L) #in meters\n", "print \"x = %0.2f m\" %x\n", "x=L/2-x #in meter\n", "print \"Centre point P from O is %0.2f m\" %(x) \n", "y=w*x**2/(2*T) #in meter\n", "print \"Height of point P, y= %0.2f m\" %y\n", "x=L/2-T*m/(w*L) #in meters\n", "z=w*(L-x)**2/(2*T) #in meters\n", "print \"Height of B above O is, z = %0.2f m\" %z \n", "print \"The mid point of the line is \",(z-y),\" meter below point B, i.e., \",(75-(z-y)),\" meter above water level.\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "x = -127.78 m\n", "Centre point P from O is 277.78 m\n", "Height of point P, y= 13.89 m\n", "Height of B above O is, z = 32.94 m\n", "The mid point of the line is 19.05 meter below point B, i.e., 55.95 meter above water level.\n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.6 : page 74" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "#Given Data :\n", "L=60 #in meter\n", "S=25*10**-2 #in meter\n", "A=61.36 #in mm**2(cross sectional area)\n", "W=0.5445 #in Kg/m\n", "UTS=42.20 #in Kg/mm**2\n", "T=W*L**2/(8*S) #in Kg\n", "B_strength=UTS*A #in Kg\n", "SafetyFactor=B_strength/T #unitless\n", "print \"Factor of safety =\", round(SafetyFactor,2) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Factor of safety = 2.64\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.7 : page 75" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "#Given Data :\n", "L=220 #in meter\n", "W=0.604 #in Kg/m\n", "T_strength=5758 #in Kg\n", "SafetyFactor=2 #unitless\n", "T=T_strength/SafetyFactor #in Kg\n", "S=W*L**2/(8*T) #in meter\n", "print \"Sag = %0.2f m \" %S " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Sag = 1.27 m \n" ] } ], "prompt_number": 20 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.8 : page 75" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given Data :\n", "W=850/1000 #in Kg/m\n", "US=7950 #in kg\n", "L=275 #in meter\n", "h=8 #in meter(ground clearance)\n", "SafetyFactor=2 #unitless\n", "T=US/SafetyFactor #in Kg\n", "S=W*L**2/(8*T) #in meter\n", "H=h+S #in meter\n", "print \"Height above the ground = %0.2f m \" %H" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Height above the ground = 10.02 m \n" ] } ], "prompt_number": 21 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.9 : page 76" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import floor\n", "#Given Data :\n", "m=1/9 #unitless\n", "EL=33 #in K\n", "EbyE1=1+(1+m)+(1+3*m+m**2) #assumed\n", "E=EL/sqrt(3) #in KV\n", "E1=E/EbyE1 #in KV\n", "print \"E1 = %0.2f kV\" %E1\n", "E2=(1+m)*E1 #in KV\n", "print \"E2 = %0.2f kV\" %E2 \n", "E3=(1+3*m+m**2)*E1 #in KV\n", "print \"E3 = %0.2f kV\" %E3 \n", "E=E1+E2+E3 #in KV\n", "Eff=E/(3*E3) \n", "Eff*=100 # %\n", "print \"String Efficiency = %.f %%\" %floor(Eff)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "E1 = 5.51 kV\n", "E2 = 6.12 kV\n", "E3 = 7.42 kV\n", "String Efficiency = 85 %\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.10 : page 77" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given Data :\n", "#Applying KCL we get I1+i1=I2+ix and I2+i2=I3+iy\n", "#On solving we get : 1*2*E1=1*1*E2+0*1*E3 and 0*2*E1=-1*2*E2+1*3*E3 \n", "E1byE=1/(1+(154/155)+(166/155)) #assumed\n", "E2byE=(154/155)*E1byE #assumed\n", "E3byE=(166/155)*E1byE #assumed\n", "Eff=1/((3*(166/155)*E1byE))\n", "Eff*=100 # %\n", "print \"String Efficiency = %.f %%\" %Eff " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "String Efficiency = 95 %\n" ] } ], "prompt_number": 29 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.11 - page : 78" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given Data :\n", "L=200 #in meter\n", "W=684/1000 #in Kg/m\n", "T=1450 #in Kg\n", "S=W*L**2/(8*T) #in meter\n", "print \"Sag = %0.2f m\" %S" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Sag = 2.36 m\n" ] } ], "prompt_number": 30 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 3.12 : page 78" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt\n", "#Given Data :\n", "L=220 #in meter\n", "T=586 #in Kg\n", "Wc=0.62 #in Kg\n", "Ww=39.2*0.94/100 #in Kg\n", "Wr=sqrt(Wc**2+Ww**2) #in Kg\n", "cos_theta=Wc/Wr #unitless\n", "Sv=Wr*L**2*cos_theta/(8*T) #in meter\n", "print \"Vertical Sag = %0.2f m\" %Sv \n", "# Answer is not accurate in the textbook." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Vertical Sag = 6.40 m\n" ] } ], "prompt_number": 34 } ], "metadata": {} } ] }