{ "metadata": { "name": "", "signature": "sha256:ce73d802673a1107e52bf47eb7b2328d569cd7caf2e704d6bf5c2e992f46aa53" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 5 - The first law and the dynamic open system" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 1 - Pg 68" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate the work done by the system and power\n", "#Initialization of variables\n", "rate= 5 #lbm/sec\n", "Q=50 #Btu/s\n", "h2=1020 #Btu/lbm\n", "h1=1000 #Btu/lbm\n", "V2=50 #ft/s\n", "V1=100 #ft/s\n", "J=778\n", "g=32.2 #ft/s^2\n", "gc=g\n", "Z2=0\n", "Z1=100. #ft\n", "#calculations\n", "dw=Q/rate -(h2-h1) -(V2**2- V1**2)/(2*gc*J) -g/gc *(Z2-Z1)/J\n", "power=dw*rate\n", "#results\n", "print '%s %.1f %s' %(\"work done by the system =\",dw,\"Btu/lbm\")\n", "print '%s %.1f %s' %(\"\\n Power =\",power,\"Btu/s\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "work done by the system = -9.7 Btu/lbm\n", "\n", " Power = -48.6 Btu/s\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2 - Pg 69" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate the area of inlet pipe\n", "#Initialization of variables\n", "V=100 #ft/s\n", "v=15. #lbm/ft^3\n", "m=5. #lbm/s\n", "#calculations\n", "A=m*v/V\n", "#results\n", "print '%s %.2f %s' %(\"Area of inlet pipe =\",A,\"ft^2\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Area of inlet pipe = 0.75 ft^2\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3 - Pg 79" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate the final temperature of the steam and change in temperature\n", "#Initialization of variables\n", "P=100. #psia\n", "#calculations\n", "print '%s' %(\"From table B-4\")\n", "h=1187.2 #Btu/lbm\n", "t1=328 #F\n", "t2=540 #F\n", "dt=t2-t1\n", "#results\n", "print '%s %d %s' %(\"Final temperature of the steam =\",t2,\"F\")\n", "print '%s %d %s' %(\"\\n Change in temperature =\",dt,\"F\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "From table B-4\n", "Final temperature of the steam = 540 F\n", "\n", " Change in temperature = 212 F\n" ] } ], "prompt_number": 3 } ], "metadata": {} } ] }