1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
{
"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
}
|
