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diff --git a/Basic_Principles_And_Calculations_In_Chemical_Engineering/ch29.ipynb b/Basic_Principles_And_Calculations_In_Chemical_Engineering/ch29.ipynb new file mode 100644 index 00000000..db601ca5 --- /dev/null +++ b/Basic_Principles_And_Calculations_In_Chemical_Engineering/ch29.ipynb @@ -0,0 +1,290 @@ +{ + "metadata": { + "name": "" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 29 : Humidity Charts and their Uses" + ] + }, + { + "cell_type": "heading", + "level": 3, + "metadata": {}, + "source": [ + "Example 29.1 page no. 895\n" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "# determining properties of moist air from the humidity chart\n", + "\n", + "# Variables\n", + "DBT = 90. ;\t\t\t# Dry bulb temperature - [degree F]\n", + "WBT = 70. ;\t\t\t# Wet bulb temperature - [degree F]\n", + "\n", + "#Get point A using DBT & WBT. Following information is obtained from humidity chart, fig. E29.1\n", + "# Results\n", + "print '(a) The Dew point is located at point B or about 60 degree F, using constant humidity line.'\n", + "print ' (b) By interpolation between 40%% and 30%% RH , you can find point A is at 37%% relative humidity .'\n", + "print ' (c) You can read humidity from the righthand ordinate as 0.0112 lb H2O/lb dry air .'\n", + "print ' (d) By interpolation again between 14.0 cubic feet/lb and 14.5 cubic feet/lb lines , you can find humid volume to be 14.1 cubic feet/lb dry air.'\n", + "print ' (e) The enthalpy value of saturated air with WBT 70 degree F is 34.1 Btu/lb dry air .'\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "(a) The Dew point is located at point B or about 60 degree F, using constant humidity line.\n", + " (b) By interpolation between 40%% and 30%% RH , you can find point A is at 37%% relative humidity .\n", + " (c) You can read humidity from the righthand ordinate as 0.0112 lb H2O/lb dry air .\n", + " (d) By interpolation again between 14.0 cubic feet/lb and 14.5 cubic feet/lb lines , you can find humid volume to be 14.1 cubic feet/lb dry air.\n", + " (e) The enthalpy value of saturated air with WBT 70 degree F is 34.1 Btu/lb dry air .\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 3, + "metadata": {}, + "source": [ + " Example 29.2 page no. 897\n" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "# Heating at constant Humidity\n", + "\n", + "# Solution fig. E29.2\n", + "\n", + "# Variables\n", + "DBT1 = 38 ;\t\t\t# Initial dry bulb temperature - [degree C]\n", + "DBT2 = 86 ;\t\t\t# Final dry bulb temperature - [degree C]\n", + "RH1 = 49 ;\t\t\t# Relative humidity - [%]\n", + "\n", + "#A is initial and B is final point , see fig. E29.2 . Dew point is obtained graphically and it is 24.8 degree C,therefore\n", + "print 'The Dew point is unchanged in the process because humidity is unchanged, and it is located at 24.8 degree C.'\n", + "\n", + "# Calculations\n", + "# Additional data is obtained from humidity chart , according to book data is as follows\n", + "A_Hsat = 90.0 ;\t\t\t# Enthalpy of saturation at point A- [kJ/kg]\n", + "A_dH = -0.5 ;\t\t\t#Enthalpy deviation-[kJ/kg]\n", + "A_Hact = A_Hsat + A_dH ;\t\t\t# Actual enthalpy at point A -[kJ/kg]\n", + "B_Hsat = 143.3 ;\t\t\t# Enthalpy of saturation at point B- [kJ/kg]\n", + "B_dH = -3.3 ;\t\t\t#Enthalpy deviation -[kJ/kg]\n", + "B_Hact = B_Hsat + B_dH ;\t\t\t# Actual enthalpy at point B -[kJ/kg]\n", + "\n", + "\t\t\t# Energy balance reduces to Q = del_H \n", + "del_H = B_Hact - A_Hact ;\t\t\t# Total change in enthalpy - [kJ/kg]\n", + "v = 0.91 ;\t\t\t# Specific volume of moist air at point A -[cubic metre / kg]\n", + "Q = del_H/v ;\t\t\t# Heat added per cubic metre of inital moist air -[kJ]\n", + "\n", + "# Results\n", + "print ' Heat added per cubic metre of inital moist air is %.1f kJ.'%Q\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The Dew point is unchanged in the process because humidity is unchanged, and it is located at 24.8 degree C.\n", + " Heat added per cubic metre of inital moist air is 55.5 kJ.\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 3, + "metadata": {}, + "source": [ + " Example 29.3 page no. 898\n" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "# Cooling and Humidification using a Water Spray\n", + "\n", + "# Solution fig. E29.3b\n", + "\n", + "# Variables\n", + "DBT1 = 40 ;\t\t\t# Initial dry bulb temperature - [degree C]\n", + "DBT2 = 27 ;\t\t\t# Final dry bulb temperature - [degree C]\n", + "\n", + "# Process is assumed to be adiabatic, therefore wet bulb temperature is constant\n", + "WBT1 = 22 ;\t\t\t# Initial wet bulb temperature - [degree C]\n", + "WBT2 = WBT1 ;\t\t\t# Final wet bulb temperature - [degree C]\n", + "\n", + "# Calculations\n", + "#A is initial and B is final point , see fig. E29.3b . Humidity is obtained from humidity chart, according to book the respective humidities are as follows\n", + "H_B = 0.0145 ;\t\t\t# Humidity at point B -[kg H2O/kg dry air]\n", + "H_A = 0.0093 ;\t\t\t# Humidity at point A -[kg H2O/kg dry air]\n", + "Diff = H_B - H_A ;\t\t\t# Moisture added in kg per kilogram of dry air going through humidifier -[kg H2O/kg dry air] \n", + "\n", + "# Results\n", + "print 'Moisture added per kilogram of dry air going through humidifier is %.4f kg H2O.'%Diff\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Moisture added per kilogram of dry air going through humidifier is 0.0052 kg H2O.\n" + ] + } + ], + "prompt_number": 3 + }, + { + "cell_type": "heading", + "level": 3, + "metadata": {}, + "source": [ + " Example 29.4 page no. 900\n" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "# Combined Material and Energy Balance for a Cooling Tower\n", + "\n", + "# Solution fig. E29.4\n", + "\n", + "# Variables\n", + "c_bl = 8.30 * 10**6 ;\t\t\t# Capacity of blower - [cubic feet/hr]\n", + "DBT_A = 80 ;\t\t\t# Initial dry bulb temperature of moist air - [degree F]\n", + "DBT_B = 95 ;\t\t\t# Final dry bulb temperature of exit air - [degree F]\n", + "WBT_A = 65 ;\t\t\t# Initial wet bulb temperature of moist air - [degree F]\n", + "WBT_B = 90 ;\t\t\t# Final wet bulb temperature of exit air - [degree F]\n", + "T1_H2O = 120 ;\t\t\t# Initial temperature of water - [degree F]\n", + "T2_H2O = 90 ;\t\t\t# Final temperature of water - [degree F]\n", + "\n", + "#A is initial and B is final point , see fig. E29.4 . Humidity is obtained from humidity chart, according to book the respective humidities are as follows\n", + "H_A = 0.0098; \t\t\t# Humidity of air at A - [lb H2O / lb dry air]\n", + "H1_A = 69 ;\t\t\t# Humidity of air at A - [grains H2O / lb dry air]\n", + "\n", + "# Calculations\n", + "delH_A = 30.05 - 0.12; \t\t\t# Enthalpy of entering air -[Btu/lb dry air]\n", + "v_A = 13.82 ;\t\t\t# Specific volume of entering air -[cubic feet/lb dry air]\n", + "H_B = 0.0297;\t\t\t# Humidity of air at B - [lb H2O / lb dry air]\n", + "H1_B = 208 ;\t\t\t# Humidity of air at B - [grains H2O / lb dry air]\n", + "delH_B = 55.93 - 0.10 ;\t\t\t# Enthalpy of exit air -[Btu/lb dry air]\n", + "v_B = 14.65 ;\t\t\t# Specific volume of exit air -[cubic feet/lb dry air]\n", + "Eq_A = c_bl /v_A ;\t\t\t# Entering dry air equivalent of capacity of blower -[lb dry air]\n", + "\n", + "# Reference temperature for water stream is 32 degree F \n", + "del_H1_H2O = 1*(T1_H2O - 32) ;\t\t\t#Enthalpy of entering water -[Btu/lb H2O]\n", + "del_H2_H2O = 1*(T2_H2O - 32) ;\t\t\t#Enthalpy of exit water -[Btu/lb H2O]\n", + "tr_H2O = H_B - H_A ;\t\t\t# Transfer of water to air -[lb H2O / lb dry air] \n", + "\n", + "# Energy balance around the entire process yields W -\n", + "W = (delH_B - del_H2_H2O*tr_H2O - delH_A)/(del_H1_H2O - del_H2_H2O) ;\t\t\t# Water entering tower - [lb H2O/lb dry air]\n", + "W1 = W - tr_H2O ;\t\t\t# Water leaving tower -[lb H2O/lb dry air]\n", + "Total_W1 = W1* Eq_A ;\t\t\t# Total water leaving tower -[lb/hr]\n", + "\n", + "# Results\n", + "print 'Amount of water cooled per hour is %.2e lb/hr .'%Total_W1\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Amount of water cooled per hour is 4.83e+05 lb/hr .\n" + ] + } + ], + "prompt_number": 4 + }, + { + "cell_type": "heading", + "level": 3, + "metadata": {}, + "source": [ + " Example 29.5 page no. 902\n" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "# Drying of Chlorella\n", + "\n", + "# Solution fig. E29.5\n", + "\n", + "# Variables\n", + "W = 100 ;\t\t\t# Amount of entering water -[lb/hr]\n", + "H1 = .020 ;\t\t\t# Humidity of entering air -[lb H2O / lb dry air]\n", + "T1 = 155 ;\t\t\t#Temperature of entering air -[degree F]\n", + "DTB = 110 ;\t\t\t# Dry bulb temperature of exit air -[degree F]\n", + "WTB = 100 ;\t\t\t# Wet bulb temperature of exit air -[degree F]\n", + "\n", + "# Additional data is obtained from humidity chart, it is as follows\n", + "H2 = .0405 ;\t\t\t#Humidity of exit air -[lb H2O / lb dry air]\n", + "\n", + "# Calculations\n", + "del_H = H2 - H1 ;\t\t\t# Change in humidity betwween two states -[lb H2O / lb dry air]\n", + "air_in = (W*1.02)/(del_H * 1) ;\t\t\t# Amount of wet air entering -[lb]\n", + "\n", + "mol_air = 29. ;\t\t\t# Molecular wt. of air -[lb]\n", + "Ref_T = 32 + 460. ;\t\t\t# Reference temperature - [ degree R]\n", + "gi_T = 90 + 460.; \t\t\t# Given temperature on which calculation is based - [degree R] \n", + "air = (air_in *359*gi_T)/( mol_air*Ref_T) ;\t\t\t# Air consumption of dryer at 90 degree F and 1 atm -[cubic feet]\n", + "\n", + "# Results\n", + "print 'Air consumption of dryer at 90 degree F and 1 atm is %.2e cubic feet .'%air\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Air consumption of dryer at 90 degree F and 1 atm is 6.89e+04 cubic feet .\n" + ] + } + ], + "prompt_number": 5 + }, + { + "cell_type": "code", + "collapsed": true, + "input": [], + "language": "python", + "metadata": {}, + "outputs": [], + "prompt_number": 5 + } + ], + "metadata": {} + } + ] +}
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