{ "metadata": { "name": "", "signature": "sha256:756d82bd4f6b1c40b9796c02104f4ba9dd307f7a3eb5083116664c3ed159b9c9" }, "nbformat": 3, "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": {} } ] }