[75] | 1 | #*------------------------------------------------------------------- |
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| 2 | * EMSO Model Library (EML) Copyright (C) 2004 - 2007 ALSOC. |
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[57] | 3 | * |
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[75] | 4 | * This LIBRARY is free software; you can distribute it and/or modify |
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| 5 | * it under the therms of the ALSOC FREE LICENSE as available at |
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| 6 | * http://www.enq.ufrgs.br/alsoc. |
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| 7 | * |
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| 8 | * EMSO Copyright (C) 2004 - 2007 ALSOC, original code |
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| 9 | * from http://www.rps.eng.br Copyright (C) 2002-2004. |
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| 10 | * All rights reserved. |
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| 11 | * |
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| 12 | * EMSO is distributed under the therms of the ALSOC LICENSE as |
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| 13 | * available at http://www.enq.ufrgs.br/alsoc. |
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| 14 | * |
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| 15 | *-------------------------------------------------------------------- |
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| 16 | * Model of a centrifugal pump |
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| 17 | *-------------------------------------------------------------------- |
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| 18 | * - Assumptions |
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| 19 | * * Steady State |
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| 20 | * * Only Liquid |
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| 21 | * * Adiabatic |
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| 22 | * * Isentropic |
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| 23 | * |
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| 24 | *---------------------------------------------------------------------- |
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| 25 | * Author: Andrey Copat, Estefane S. Horn, Marcos L. Alencastro |
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| 26 | * $Id: pump.mso 75 2006-12-08 19:01:49Z paula $ |
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| 27 | *--------------------------------------------------------------------*# |
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| 28 | |
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[57] | 29 | using "streams"; |
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| 30 | using "pressure_changers/flux_machine_basic"; |
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| 31 | |
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| 32 | Model centrifugal_pump as flux_machine_basic |
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| 33 | |
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| 34 | PARAMETERS |
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| 35 | ext NComp as Integer (Brief = "Number of chemical components", Lower = 1); |
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| 36 | ext PP as CalcObject (Brief = "External Physical Properties"); |
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| 37 | Mw(NComp) as molweight (Brief = "Molar Weight"); |
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| 38 | Eff as positive (Default = 0.72, Brief = "Pump Efficiency"); |
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| 39 | Meff as positive (Default = 0.95, Brief = "Brake Efficiency"); |
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| 40 | Beta as positive (Default = 0, Brief = "Volumetric Expansivity", Unit = "1/K"); |
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| 41 | g as acceleration (Brief = "Gravity Acceleration", Default = 9.81); |
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| 42 | N as vel_angular (Brief = "Rotation", Default = 100); |
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| 43 | Lev as length (Brief = "Loss Friction", Default = 0); |
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| 44 | |
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| 45 | VARIABLES |
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| 46 | rho as dens_mass (Brief = "Specific Mass", Unit="kg/m^3"); |
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| 47 | Cp as cp_mol (Brief = "Heat Capacity", Unit="kJ/kmol/K"); |
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| 48 | FPower as power (Brief = "Fluid Power", Unit="kW"); |
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| 49 | BPower as power (Brief = "Brake Power",Unit="kW"); |
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| 50 | EPower as power (Brief = "Eletrical Potency", Unit="kW"); |
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| 51 | Pdiff as press_delta (Brief = "Pressure Increase", Unit="kPa"); |
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| 52 | Pratio as positive (Brief = "Pressure Ratio"); |
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| 53 | Head as head (Brief = "Head Developed", Unit="kJ/kmol"); |
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| 54 | Head_is as head (Brief = "Isoentripic Head", Unit="kJ/kmol"); |
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| 55 | Mwm as molweight (Brief = "Mixture Molar Weight"); |
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| 56 | pvm as pressure (Brief = "Mixture Vapour Pressure", Unit = "kPa"); |
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| 57 | NPSHa as length (Brief = "Available Net Positive Suction Head"); |
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| 58 | NS as positive (Brief = "Specific Speed", Unit = "(rpm*(gal/min)^0.5)/(m^3/4)"); |
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| 59 | Q as flow_vol (Brief = "Volumetric Flow Rate"); |
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| 60 | vm as vol_mol (Brief = "Mixture Molar Volume", Unit = "m^3/kmol"); |
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| 61 | |
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| 62 | SET |
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| 63 | Mw = PP.MolecularWeight(); |
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| 64 | |
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| 65 | EQUATIONS |
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| 66 | #Mixtures Properties |
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| 67 | "Calculate Mwm for Inlet Mixture" |
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| 68 | Mwm = sum(Mw([1:NComp])*Inlet.z([1:NComp])); |
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| 69 | |
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| 70 | "Calculate Cp Using a External Physical Properties Routine" |
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| 71 | Cp = PP.LiquidCp(Inlet.T,Inlet.P,Inlet.z); |
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| 72 | |
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| 73 | "Calculate rho using a External Physical Properties Routine" |
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| 74 | rho = PP.LiquidDensity(Inlet.T,Inlet.P,Inlet.z); |
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| 75 | |
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| 76 | "Calculate Mixture Vapour Pressure" |
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| 77 | [pvm] = PP.BubbleP(Inlet.T,Inlet.z); |
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| 78 | |
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| 79 | "Calculate Outlet Vapour Fraction" |
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| 80 | Outlet.v = PP.VapourFraction(Outlet.T, Outlet.P, Outlet.z); |
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| 81 | |
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| 82 | "Calculate Liquid Molar Volume" |
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| 83 | vm = PP.LiquidVolume(Inlet.T,Inlet.P,Inlet.z); |
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| 84 | |
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| 85 | #Mass and Energy Balance and Pump Equations |
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| 86 | "Calculate Outlet Stream Pressure" |
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| 87 | Outlet.P = Inlet.P + Pdiff; |
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| 88 | |
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| 89 | "Pratio Definition" |
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| 90 | Outlet.P = Inlet.P * Pratio; |
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| 91 | |
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| 92 | "Calculate Isentropic Head" |
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| 93 | Head_is = Pdiff * Mwm/rho; |
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| 94 | |
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| 95 | "Calculate Real Head" |
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| 96 | Head = Head_is/(Eff*Meff); |
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| 97 | |
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| 98 | "Calculate Outlet Enthalpy" |
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| 99 | Outlet.h - Inlet.h = Head; |
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| 100 | |
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| 101 | "Calculate Fluid Power" |
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| 102 | FPower = Head_is * Inlet.F; |
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| 103 | |
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| 104 | "Calculate Brake Power" |
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| 105 | BPower * Eff = FPower; |
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| 106 | |
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| 107 | "Calculate Eletric Power" |
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| 108 | BPower = EPower * Meff; |
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| 109 | |
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| 110 | "Calculate Outlet Temperature" |
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| 111 | (Outlet.T - Inlet.T) * Cp = (Outlet.h - Inlet.h) - Pdiff * Mwm / rho * (1 - Beta * Inlet.T); |
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| 112 | |
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| 113 | "Molar Balance" |
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| 114 | Outlet.F = Inlet.F; |
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| 115 | |
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| 116 | "Calculate Outlet Composition" |
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| 117 | Outlet.z = Inlet.z; |
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| 118 | |
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| 119 | "Calculate Net Positive Suction Head" |
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| 120 | NPSHa = - Lev + (Inlet.P - pvm)/(g*rho); #If Inlet.P is the suction pump pressure, Lev is 0. |
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| 121 | |
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| 122 | "Calculate Volumetric Flow Rate" |
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| 123 | Q = Inlet.F*vm; |
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| 124 | |
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| 125 | "Calculate Specific Speed" |
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| 126 | NS = N*(Q^0.5)/(Head^3/4); |
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| 127 | |
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| 128 | end |
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| 129 | |
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| 130 | |
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[1] | 131 | #*------------------------------------------------------------------- |
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[75] | 132 | * Model of a pump (simplified, used in distillation column model) |
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[1] | 133 | *-------------------------------------------------------------------- |
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| 134 | * |
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| 135 | * Streams: |
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| 136 | * * an inlet stream |
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| 137 | * * an outlet stream |
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| 138 | * |
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| 139 | * Specify: |
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| 140 | * * the inlet stream |
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| 141 | * * the pump press delta |
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| 142 | * |
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| 143 | *---------------------------------------------------------------------- |
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| 144 | * Author: Paula B. Staudt |
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| 145 | *--------------------------------------------------------------------*# |
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| 146 | |
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| 147 | Model pump |
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| 148 | PARAMETERS |
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| 149 | ext PP as CalcObject; |
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| 150 | ext NComp as Integer; |
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| 151 | |
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| 152 | VARIABLES |
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| 153 | in Inlet as stream; |
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| 154 | out Outlet as stream_therm; |
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| 155 | |
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| 156 | dP as press_delta (Brief="Pump head"); |
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| 157 | |
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| 158 | EQUATIONS |
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| 159 | "Molar Balance" |
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| 160 | Inlet.F = Outlet.F; |
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| 161 | Inlet.z = Outlet.z; |
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| 162 | |
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| 163 | "Pump head" |
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| 164 | Outlet.P = Inlet.P + dP; |
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| 165 | |
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| 166 | "Temperature" |
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| 167 | Outlet.T = Inlet.T; |
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| 168 | |
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| 169 | "Vapourisation Fraction" |
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| 170 | Outlet.v = Inlet.v; |
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| 171 | end |
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