{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 3 - Temperature and Heat" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 1 - Pg 33" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the mass of water required per pound of iron \n", "import math\n", "#Initialization of variables\n", "T1=500 #F\n", "T2=100 #F\n", "Tf=75 #F\n", "cpi=0.120 #B/lb F\n", "cpw=1.0 #B/lb F\n", "#calculations\n", "Qw=1*cpw*(T2-Tf)\n", "Qi=-1*cpi*(T2-T1)\n", "mw=Qi/Qw\n", "#results\n", "print '%s %.2f %s' %(\"Mass of water = \",mw,\"lb water/lb iron\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Mass of water = 1.92 lb water/lb iron\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2 - Pg 34" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the net heat transferred\n", "import math\n", "import scipy\n", "from scipy import integrate\n", "#Initialization of variables\n", "m=5 #lb\n", "T1=1540+460 #R\n", "T2=540+460 #R\n", "#calculations\n", "def q(T):\n", "\tcp=m*(0.248+0.448*math.pow(10,-8) *T*T)\n", "\treturn cp;\n", "\n", "Q=scipy.integrate.quad(q,T1,T2)\n", "#results\n", "print '%s %d %s' %(\"Heat transferred =\",Q[0],\"Btu\")\n", "print '%s' %(\"The answer is a bit different due to rounding off error in textbook\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Heat transferred = -1292 Btu\n", "The answer is a bit different due to rounding off error in textbook\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3 - Pg 36" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the heat required for the process\n", "#Initialization of variables\n", "Tm=235 #F\n", "Tb=832 #F\n", "T=70 #F\n", "cps=0.18 #B/lb F\n", "cpl=0.235 #B/lb F\n", "Lf=15.8 #B/lb\n", "Lv=120 #B/lb\n", "m=10 #lb\n", "#calculations\n", "Qa=m*cps*(Tm-T)\n", "Qb=m*Lf\n", "Qc=m*cpl*(Tb-Tm)\n", "Qd=m*Lv\n", "Q=Qa+Qb+Qc+Qd\n", "#results\n", "print '%s %.1f %s' %(\"Heat required =\",Q,\"Btu\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Heat required = 3057.9 Btu\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4 - Pg 36" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the mass of ice required for the process\n", "#Initialization of variables\n", "T1=22 #F\n", "T2=32 #F\n", "T3=40 #F\n", "T4=70 #F\n", "cps=0.501 #B/lb F\n", "cpw=1 #B/lb F\n", "Lf=143.3 #B/lb\n", "m=40 #lb\n", "#calculations\n", "Qa=cps*(T2-T1)\n", "Qb=Lf\n", "Qc=cpw*(T3-T2)\n", "Qd=m*cpw*(T3-T4)\n", "mi=-Qd/(Qa+Qb+Qc)\n", "#results\n", "print '%s %.2f %s' %(\"Mass of ice required =\",mi,\"lb ice\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Mass of ice required = 7.68 lb ice\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5 - Pg 37" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the extra mass of ice required\n", "#Initialization of variables\n", "T1=22 #F\n", "T2=32 #F\n", "T3=40 #F\n", "T4=70 #F\n", "cps=0.501 #B/lb F\n", "cpw=1 #B/lb F\n", "Lf=143.3 #B/lb\n", "m=40 #lb\n", "cp=0.092\n", "mc=10\n", "#calculations\n", "Qa=cps*(T2-T1)\n", "Qb=Lf\n", "Qc=cpw*(T3-T2)\n", "Qe=mc*cp*(T3-T4)\n", "mi=-Qe/(Qa+Qb+Qc)\n", "#results\n", "print '%s %.3f %s' %(\"Extra Mass of ice required =\",mi,\"lb ice\")" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Extra Mass of ice required = 0.177 lb ice\n" ] } ], "prompt_number": 6 } ], "metadata": {} } ] }