{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 2 - Ionization" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 1: pg 22" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "the breakdown strength of air for 0.1mm air gap is (kV/cm.) = 43.447\n", "\n", "the breakdown strength of air for 20 cm air gap is (kV/cm.) = 25.58\n" ] } ], "source": [ "#example 2.1\n", "#calculation of breakdown strength of air\n", "\n", "#given data\n", "d1=0.1#length(in cm) of the gap\n", "d2=20#length(in cm) of the gap\n", "\n", "#calculation\n", "#from equation of breakdown strength\n", "E1=24.22+(6.08/(d1**(1./2)))#for gap d1\n", "E2=24.22+(6.08/(d2**(1./2)))#for gap d2\n", "#results\n", "print 'the breakdown strength of air for 0.1mm air gap is (kV/cm.) = ',round(E1,3)\n", "print '\\nthe breakdown strength of air for 20 cm air gap is (kV/cm.) = ',round(E2,3)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2: pg 23" ] }, { "cell_type": "code", "execution_count": 2, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Townsend primary ioniztion coefficient is (/cm torr) = 7.675\n" ] } ], "source": [ "#example 2.2\n", "#calculation of Townsend primary ionization coefficient\n", "from math import log\n", "#given data\n", "d1=0.4#gap distance(in cm)\n", "d2=0.1#gap distance(in cm)\n", "I1=5.5*10**-8#value of current(in A)\n", "I2=5.5*10**-9#value of current(in A)\n", "\n", "#calculation\n", "#from equation of current at anode I=I0*exp(alpha*d)\n", "alpha=(log(I1/I2))*(1/(d1-d2))\n", "#results\n", "print 'Townsend primary ioniztion coefficient is (/cm torr) = ',round(alpha,3)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 3: pg 25" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "the value of Townsend secondary ionization coefficient is 9.994e-04\n" ] } ], "source": [ "#example 2.3\n", "#calculation of Townsend secondary ionization coefficient\n", "from math import exp\n", "#given data\n", "d=0.9#gap distance(in cm)\n", "alpha=7.676#value of alpha\n", "\n", "#calculation\n", "#from condition of breakdown.....gama*exp(alpha*d)=1\n", "gama=1/(exp(d*alpha))\n", "#results\n", "print '%s %.3e' %('the value of Townsend secondary ionization coefficient is ',gama)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 4: pg 26" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "the value of breakdown voltage of the spark gap is (V) = 5626.0\n", "The answer is a bit different due to rounding off error in textbook\n" ] } ], "source": [ "#example 2.4\n", "#calculation of breakdown voltage of a spark gap\n", "from math import log\n", "#given data\n", "A=15#value of A(in per cm)\n", "B=360#value of B(in per cm)\n", "d=0.1#spark gap(in cm)\n", "gama=1.5*10**-4#value of gama\n", "p=760#value of pressure of gas(in torr)\n", "\n", "#calculation\n", "#from equation of breakdown voltage\n", "V=(B*p*d)/(log((A*p*d)/(log(1+(1/gama)))))\n", "\n", "#results\n", "print 'the value of breakdown voltage of the spark gap is (V) = ',round(V)\n", "print 'The answer is a bit different due to rounding off error in textbook'\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 5: pg 26" ] }, { "cell_type": "code", "execution_count": 5, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "the value of minimum spark over voltage is (V) = 481.0\n" ] } ], "source": [ "#example 2.5\n", "#calculation of minimum spark over voltage\n", "from math import log\n", "#given data\n", "A=15#value of A(in per cm)\n", "B=360#value of B(in per cm)\n", "gama=10**-4#value of gama\n", "e=2.178#value of constant\n", "\n", "#calculation\n", "Vbmin=(B*e/A)*(log(1+(1/gama)))\n", "\n", "#results\n", "print 'the value of minimum spark over voltage is (V) = ',round(Vbmin)\n" ] } ], "metadata": { "kernelspec": { "display_name": "Python 2", "language": "python", "name": "python2" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 2 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython2", "version": "2.7.11" } }, "nbformat": 4, "nbformat_minor": 0 }