{
"metadata": {
"name": "",
"signature": "sha256:756d82bd4f6b1c40b9796c02104f4ba9dd307f7a3eb5083116664c3ed159b9c9"
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"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 1 : Basic Concepts"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.1 Page No : 9"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"L = 0.02;\t\t \t#Thicness of stainless steel plate in m\n",
"T = [550,50];\t\t\t#Temperatures at both the faces in degree C\n",
"k = 19.1;\t\t \t#Thermal Conductivity of stainless steel at 300 degree C in W/m.K\n",
" \n",
"# Calculations\n",
"q = ((k*(T[0]-T[1]))/(L*1000));\t\t\t#Heat transfered per uni area in kW/m**2\n",
"\n",
"# Results\n",
"print 'The heat transfered through the material per unit area is %3.1f kW/m**2'%(q)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The heat transfered through the material per unit area is 477.5 kW/m**2\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.2 Page No : 11"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"L = 1.;\t\t\t#Length of the flat plate in m\n",
"w = 0.5;\t\t\t#Width of the flat plate in m\n",
"T = 30.;\t\t\t#Air stream temperature in degree C\n",
"h = 30.;\t\t\t#Convective heat transfer coefficient in W/m**2.K\n",
"Ts = 300.;\t\t\t#Temperature of the plate in degree C\n",
"\n",
"# Calculations\n",
"A = (L*w) \t\t\t#Area of the plate in m**2\n",
"Q = (h*A*(Ts-T)/(1000));\t\t\t#Heat transfer in kW\n",
"\n",
"# Results\n",
"print 'Heat transfer rate is %3.2f kW'%(Q)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Heat transfer rate is 4.05 kW\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.3 Page No : 11"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"T = 55.\t\t\t#Surface temperature in degree C\n",
"\n",
"# Calculations\n",
"q = (5.6697*10**-8*(273+T)**4)/1000;\t\t\t#The rate at which the radiator emits radiant heat per unit area if it behaves as a black body in kW/m**2\n",
"\n",
"# Results\n",
"print 'The rate at which the radiator emits radiant heat per unit area is %3.2f kW/m**2'%(q)\n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The rate at which the radiator emits radiant heat per unit area is 0.66 kW/m**2\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.5 Page No : 20"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"k = 0.145;\t\t\t#Thermal conductivity of Firebrick in W/m.K\n",
"e = 0.85;\t\t\t#Emissivity\n",
"L = 0.145;\t\t\t#Thickness of the wall in m\n",
"Tg = 800.;\t\t\t#Gas temperature in degree C\n",
"Twg = 798.;\t\t\t#Wall temperature ion gas side in degree C\n",
"hg = 40.;\t\t\t#Film conductance on gas side in W/m**2.K\n",
"hc = 10.;\t\t\t#Film conductance on coolant side in W/m**2.K\n",
"F = 1.; \t\t\t#Radiation Shape factor between wall and gas\n",
"\n",
"# Calculations\n",
"R1 = (((e*5.67*10**-8*F*((Tg+273)**4-(Twg+273)**4))/(Tg-Twg))+(1./hg));\t\t\t#Thermal resistance inverse\n",
"R2 = (L/k); \t \t\t#Thermal resistance\n",
"R3 = (1./hc);\t \t \t#Thermal resistance\n",
"U = 1./((1./R1)+R2+R3);\t\t\t#Overall heat transfer coefficient in W/m**2.K\n",
"\n",
"# Results\n",
"print 'Overall heat transfer coefficient is %3.3f W/m**2.K'%(U)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Overall heat transfer coefficient is 0.906 W/m**2.K\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.6 Page No : 21"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"D = 0.05;\t\t\t#Outside diameter of the pipe in m\n",
"e = 0.8;\t\t\t#Emmissivity\n",
"T = 30;\t\t\t#Room Temperature in degree C\n",
"Ts = 250;\t\t\t#Surface temperature in degree C\n",
"h = 10;\t\t\t#Convective heat transfer coefficient in W/m**2.K\n",
"\n",
"# Calculations\n",
"q = ((h*3.14*D*(Ts-T))+(e*3.14*D*5.67*10**-8*((Ts+473)**4-(T+273)**4)));\t\t\t#Heat loss per unit length of pipe in W/m\n",
"\n",
"# Results\n",
"print 'Heat loss per unit length of pipe is %3.1f W/m'%(q) \n",
"\n",
"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Heat loss per unit length of pipe is 2231.3 W/m\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 1.7 Page No : 21"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# Variables\n",
"A = 0.1;\t\t\t#Surface area of water heater in m**2\n",
"Q = 1000.;\t\t\t#Heat transfer rate in W\n",
"Twater = 40;\t\t\t#Temperature of water in degree C\n",
"h1 = 300;\t\t\t#Heat transfer coefficient in W/m**2.K\n",
"Tair = 40;\t\t\t#Temperature of air in degree C\n",
"h2 = 9;\t\t\t#Heat transfer coefficient in W/m**2.K \n",
"\n",
"# Calculations\n",
"Tsw = (Q/(h1*A))+Twater;\t\t\t#Temperature when used in water in degree C\n",
"Tsa = (Q/(h2*A))+Tair;\t\t\t#Temperature when used in air in degree C\n",
"\n",
"# Results\n",
"print 'Temperature when used in water is %3.1f degree C \\n \\\n",
"Temperature when used in air is %i degree C'%(Tsw,Tsa)\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Temperature when used in water is 73.3 degree C \n",
" Temperature when used in air is 1151 degree C\n"
]
}
],
"prompt_number": 7
}
],
"metadata": {}
}
]
}