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
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
|
{
"metadata": {
"name": "",
"signature": "sha256:20bf663c37cc88094e4d6e0d7e23e0cfc96b3cd4eb305559eda1ce27188b9a4a"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 9 : Thermal radiation basic\n",
"relations"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.1 Page No : 378"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math \n",
"\n",
"# Variables\n",
"T = 5527;\t\t\t#Temperature of black body in degree C\n",
"D = (1.39*10**6);\t\t\t#Diameter of the sun in km\n",
"L = (1.5*10**8);\t\t\t#Distance between the earth and sun in km\n",
"\n",
"# Calculations\n",
"q = (5.67*10**-8*(T+273)**4*D**2)/(4*L**2);\t\t\t#Rate of solar radiation in W/m**2\n",
"\n",
"# Results\n",
"print 'Rate of solar radiation on a plane normal to sun rays is %3.0f W/m**2'%(q)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Rate of solar radiation on a plane normal to sun rays is 1377 W/m**2\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.2 Page No : 383"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"T = (727+273);\t\t\t#Temperature of black body in K\n",
"l1 = 1;\t\t\t#Wavelength in micro meter\n",
"l2 = 5;\t\t\t#Wavelength in micro meter\n",
"F1 = 0.0003;\t\t\t#From Table 9.2 on page no. 385\n",
"F2 = 0.6337;\t\t\t#From Table 9.2 on page no. 385\n",
"\n",
"# Calculations\n",
"a = (5.67*10**-8*T**4)/1000;\t\t\t#Heat transfer in kW/m**2\n",
"F = (F2-F1)*a;\t\t\t#Fraction of thermal radiation emitted by the surface in kW/m**2\n",
"\n",
"# Results\n",
"print 'Fraction of thermal radiation emitted by the surface is %3.1f kW/m**2'%(F)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Fraction of thermal radiation emitted by the surface is 35.9 kW/m**2\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.3 Page No : 384"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"t = 0.8;\t\t\t#Transmittivity of glass in the region except in the wave length region [0.4,3]\n",
"T = 5555;\t\t\t#Temperature of black body in K\n",
"\n",
"# Calculations\n",
"ao = 0;\t\t\t#a0 in micro K\n",
"a1 = (0.4*T);\t\t\t#a1 for the wavelength 0.4 micro meter in micro K\n",
"a2 = (3*T);\t\t\t#a1 for the wavelength 3 micro meter in micro K\n",
"F0 = 0;\t\t\t#From Table 9.2 on page no.385\n",
"F1 = 0.10503;\t\t\t#From Table 9.2 on page no.385\n",
"F2 = 0.97644;\t\t\t#From Table 9.2 on page no.385\n",
"t1 = t*(F2-F1);\t\t\t#Average hemispherical transmittivity of glass \n",
"\n",
"# Results\n",
"print 'Average hemispherical transmittivity of glass is %3.2f'%(t1)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Average hemispherical transmittivity of glass is 0.70\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.4 Page No : 386"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"l = 0.5;\t\t\t#Wavelength at maximum intensity of radiation in micro meter\n",
"C3 = 0.289*10**-2 #mK\n",
"\n",
"# Calculations\n",
"T = C3/(l*10**-6);\t\t\t#Temperature according to Wien's print lacement law in degree C\n",
"E = (5.67*10**-8*T**4)/10**6;\t\t\t#Emissive power umath.sing Stefan-Boltzmann law in MW/m**2\n",
"\n",
"# Results\n",
"print 'Surface temperature is %3.0f K Emissive power is %3.1f MW/m**2'%(T,E)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Surface temperature is 5780 K Emissive power is 63.3 MW/m**2\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.5 Page No : 389"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"Ts = (827+273);\t\t\t#Surface temperature in degree C\n",
"E = (1.37*10**10);\t\t\t#Emmisive power in W/m**3\n",
"\n",
"# Calculations\n",
"Eblmax = (1.307*10**-5*Ts**5);\t\t\t#Maximum emissive power in W/m**3\n",
"e = (E/Eblmax);\t\t\t#Emissivity of the body \n",
"lmax = ((0.289*10**-2)/Ts)/10**-6;\t\t\t#Wavelength correspoing to the maximum spectral intensity of radiation in micro meter\n",
"\n",
"# Results\n",
"print 'Wavelength corresponding to the maximum spectral intensity of radiation is %3.2f micro meter'%(lmax)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Wavelength corresponding to the maximum spectral intensity of radiation is 2.63 micro meter\n"
]
}
],
"prompt_number": 6
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.6 Page No : 389"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"# Variables\n",
"T = (1400+273);\t\t\t#Temperature of the body in K\n",
"l = 0.65;\t\t\t#Wavelength in micro meter\n",
"e = 0.6;\t\t\t#Emissivity\n",
"\n",
"# Calculations\n",
"T = (1./((1./T)-((l*10**-6*math.log(1./e))/(1.439*10**-2))));\t\t\t#Temperature of the body in K\n",
"Tb = (T-273);\t\t\t#Temperature of the body in degree C\n",
"\n",
"# Results\n",
"print 'Temperature of the body is %3.0f degree C'%(Tb)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Temperature of the body is 1467 degree C\n"
]
}
],
"prompt_number": 7
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.7 Page No : 391"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"Ts = (37+273);\t\t\t#Temperature of metallic bar in K\n",
"T = 1100;\t\t\t#Interior temperature in K\n",
"a = 0.52;\t\t\t#Absorptivity at 1100 K\n",
"e = 0.8;\t\t\t#Emissivity at 310 K\n",
"\n",
"# Calculations\n",
"Q = (a*5.67*10**-8*T**4)/1000;\t\t\t#Rate of absorption in kW/m**2\n",
"E = (e*5.67*10**-8*Ts**4)/1000;\t\t\t#Rate of emission in kW/m**2\n",
"\n",
"# Results\n",
"print 'Rate of absorption is %3.2f kW/m**2 \\n \\\n",
"Rate of emission is %3.2f kW/m**2'%(Q,E)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Rate of absorption is 43.17 kW/m**2 \n",
" Rate of emission is 0.42 kW/m**2\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.8 Page No : 391"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"e1 = 0.3\t\t\t#Emissivity of glass upto 3 micro meter\n",
"e2 = 0.9;\t\t\t#Emissivity of glass above 3 micro meter\n",
"t = 0.8;\t\t\t#Transmittivity of glass in the region except in the wave length region [0.4,3]\n",
"\n",
"# Calculations\n",
"E = (5.67*10**-8*5780**4)/10**6;\t\t\t#Emissive power in MW/m**2\n",
"F1 = 0.10503;\t\t\t#From Table 9.2 on page no.385\n",
"F2 = 0.97644;\t\t\t#From Table 9.2 on page no.385\n",
"I = (E*10**6*(F2-F1))/10**6;\t\t\t#Total incident radiation in MW/m**2\n",
"T = (t*I);\t\t\t#Total radiation transmitted in MW/m**2\n",
"t1 = (e1*I);\t\t\t#Absorbed radiation in MW/m**2 in wavelength [0.4,3] micro meter\n",
"t2 = (e1*E*F1);\t\t\t#Absorbed radiation in MW/m**2 in wavelength not in the range [0.4,3] micro meter\n",
"t3 = (e2*(1-F2)*E);\t\t\t#Absorbed radiation in MW/m**2 in wavelength greater than 3 micro meter\n",
"R = (t1+t2+t3);\t\t\t#Total radiation absorbed in MW/m**2\n",
"\n",
"# Results\n",
"print 'Total radiation transmitted is %3.2f MW/m**2 \\n \\\n",
"Total radiation absorbed is %3.2f MW/m**2'%(T,R)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Total radiation transmitted is 44.12 MW/m**2 \n",
" Total radiation absorbed is 19.88 MW/m**2\n"
]
}
],
"prompt_number": 9
}
],
"metadata": {}
}
]
}
|
