[698] | 1 | #*------------------------------------------------------------------- |
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| 2 | * EMSO Model Library (EML) Copyright (C) 2004 - 2007 ALSOC. |
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| 3 | * |
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| 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 | * Author: Paula B. Staudt |
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| 17 | * $Id: condenser.mso 555 2008-07-18 19:01:13Z rafael $ |
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| 18 | *--------------------------------------------------------------------*# |
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| 19 | |
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| 20 | using "streams"; |
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| 21 | |
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| 22 | Model condenserSteady |
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[792] | 23 | |
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| 24 | ATTRIBUTES |
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[698] | 25 | Pallete = true; |
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| 26 | Icon = "icon/CondenserSteady"; |
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| 27 | Brief = "Model of a Steady State condenser with no thermodynamics equilibrium."; |
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| 28 | Info = |
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[792] | 29 | "== ASSUMPTIONS == |
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[698] | 30 | * perfect mixing of both phases; |
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| 31 | * no thermodynamics equilibrium. |
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[792] | 32 | |
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| 33 | == SET == |
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[698] | 34 | * the pressure drop in the condenser; |
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[792] | 35 | |
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| 36 | == SPECIFY == |
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| 37 | * the InletVapour stream; |
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| 38 | * the InletQ (the model requires an energy stream, also you can use a controller for setting the heat duty using the heat_flow model). |
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| 39 | |
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| 40 | == OPTIONAL == |
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| 41 | * the condenser model has two control ports |
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| 42 | ** TI OutletLiquid Temperature Indicator; |
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| 43 | ** PI OutletLiquid Pressure Indicator; |
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[698] | 44 | "; |
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| 45 | |
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| 46 | PARAMETERS |
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[792] | 47 | outer PP as Plugin (Brief = "External Physical Properties", Type="PP"); |
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| 48 | outer NComp as Integer (Brief = "Number of Components"); |
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[802] | 49 | |
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| 50 | Mw(NComp) as molweight (Brief = "Component Mol Weight",Hidden=true); |
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| 51 | low_flow as flow_mol (Brief = "Low Flow",Default = 1E-6, Hidden=true); |
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| 52 | zero_flow as flow_mol (Brief = "No Flow",Default = 0, Hidden=true); |
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| 53 | KfConst as area (Brief="Constant for K factor pressure drop", Default = 1, Hidden=true); |
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| 54 | |
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| 55 | VapourFlow as Switcher (Brief="Vapour Flow", Valid = ["on", "off"], Default = "on",Hidden=true); |
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[698] | 56 | |
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[802] | 57 | Kfactor as positive (Brief="K factor for pressure drop", Lower = 1E-8, Default = 1E-3); |
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[792] | 58 | Pdrop as press_delta (Brief="Pressure Drop in the condenser",Default=0, Symbol="\Delta _P"); |
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[786] | 59 | |
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[802] | 60 | SET |
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| 61 | |
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| 62 | Mw = PP.MolecularWeight(); |
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| 63 | low_flow = 1E-6 * 'kmol/h'; |
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| 64 | zero_flow = 0 * 'kmol/h'; |
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| 65 | KfConst = 1*'m^2'; |
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| 66 | |
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[698] | 67 | VARIABLES |
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[801] | 68 | in InletVapour as stream (Brief="Vapour inlet stream", PosX=0.16, PosY=0, Symbol="_{in}^{Vapour}"); |
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| 69 | out OutletLiquid as liquid_stream (Brief="Liquid outlet stream", PosX=0.53, PosY=1, Symbol="_{out}^{Liquid}"); |
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| 70 | in InletQ as power (Brief="Heat Duty", PosX=1, PosY=0.08, Symbol="Q_{in}",Protected=true); |
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[802] | 71 | |
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| 72 | rho as dens_mass (Brief ="Inlet Vapour Mass Density",Hidden=true, Symbol ="\rho"); |
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| 73 | |
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[801] | 74 | out TI as control_signal (Brief="Temperature Indicator of Condenser", Protected = true, PosX=0.50, PosY=0); |
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| 75 | out PI as control_signal (Brief="Pressure Indicator of Condenser", Protected = true, PosX=0.32, PosY=0); |
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[792] | 76 | |
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[698] | 77 | EQUATIONS |
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| 78 | |
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[802] | 79 | switch VapourFlow |
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| 80 | |
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| 81 | case "on": |
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| 82 | InletVapour.F*sum(Mw*InletVapour.z) = Kfactor *sqrt(Pdrop*rho)*KfConst; |
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| 83 | |
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| 84 | when InletVapour.F < low_flow switchto "off"; |
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| 85 | |
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| 86 | case "off": |
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| 87 | InletVapour.F = zero_flow; |
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| 88 | |
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| 89 | when InletVapour.P > OutletLiquid.P switchto "on"; |
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| 90 | |
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| 91 | end |
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| 92 | |
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[784] | 93 | "Molar Flow Balance" |
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[735] | 94 | InletVapour.F = OutletLiquid.F; |
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[784] | 95 | |
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| 96 | "Molar Composition Balance" |
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[735] | 97 | InletVapour.z = OutletLiquid.z; |
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[698] | 98 | |
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| 99 | "Energy Balance" |
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[735] | 100 | InletVapour.F*InletVapour.h = OutletLiquid.F*OutletLiquid.h + InletQ; |
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[698] | 101 | |
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[802] | 102 | "Inlet Vapour Density" |
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| 103 | rho = PP.VapourDensity(InletVapour.T, InletVapour.P, InletVapour.z); |
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| 104 | |
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[784] | 105 | "Pressure Drop" |
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| 106 | OutletLiquid.P = InletVapour.P - Pdrop; |
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[698] | 107 | |
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[792] | 108 | "Temperature indicator" |
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| 109 | TI * 'K' = OutletLiquid.T; |
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| 110 | |
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| 111 | "Pressure indicator" |
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| 112 | PI * 'atm' = OutletLiquid.P; |
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| 113 | |
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[698] | 114 | end |
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| 115 | |
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| 116 | Model condenserReact |
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| 117 | ATTRIBUTES |
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[721] | 118 | Pallete = false; |
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[698] | 119 | Icon = "icon/Condenser"; |
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| 120 | Brief = "Model of a Condenser with reaction in liquid phase."; |
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| 121 | Info = |
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| 122 | "== Assumptions == |
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| 123 | * perfect mixing of both phases; |
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| 124 | * thermodynamics equilibrium; |
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| 125 | * the reaction only takes place in liquid phase. |
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| 126 | |
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| 127 | == Specify == |
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| 128 | * the reaction related variables; |
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| 129 | * the inlet stream; |
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[735] | 130 | * the outlet flows: OutletVapour.F and OutletLiquid.F; |
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[698] | 131 | * the heat supply. |
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| 132 | |
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| 133 | == Initial Conditions == |
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[735] | 134 | * the condenser temperature (OutletLiquid.T); |
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[698] | 135 | * the condenser liquid level (Level); |
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[735] | 136 | * (NoComps - 1) OutletLiquid (OR OutletVapour) compositions. |
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[698] | 137 | "; |
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| 138 | |
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[721] | 139 | PARAMETERS |
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| 140 | outer PP as Plugin(Type="PP"); |
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[698] | 141 | outer NComp as Integer; |
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[721] | 142 | |
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| 143 | V as volume (Brief="Condenser total volume"); |
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| 144 | Across as area (Brief="Cross Section Area of reboiler"); |
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[698] | 145 | |
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[721] | 146 | stoic(NComp) as Real (Brief="Stoichiometric matrix"); |
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| 147 | Hr as energy_mol; |
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| 148 | Initial_Level as length (Brief="Initial Level of liquid phase"); |
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| 149 | Initial_Temperature as temperature (Brief="Initial Temperature of Condenser"); |
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| 150 | Initial_Composition(NComp) as fraction (Brief="Initial Liquid Composition"); |
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| 151 | |
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| 152 | VARIABLES |
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[698] | 153 | |
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[735] | 154 | in InletVapour as stream (Brief="Vapour inlet stream", PosX=0.1164, PosY=0, Symbol="_{inV}"); |
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| 155 | out OutletLiquid as liquid_stream (Brief="Liquid outlet stream", PosX=0.4513, PosY=1, Symbol="_{outL}"); |
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| 156 | out OutletVapour as vapour_stream (Brief="Vapour outlet stream", PosX=0.4723, PosY=0, Symbol="_{outV}"); |
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[721] | 157 | InletQ as power (Brief="Cold supplied", PosX=1, PosY=0.6311, Symbol="_{in}"); |
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[698] | 158 | |
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[721] | 159 | M(NComp) as mol (Brief="Molar Holdup in the tray"); |
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| 160 | ML as mol (Brief="Molar liquid holdup"); |
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| 161 | MV as mol (Brief="Molar vapour holdup"); |
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| 162 | E as energy (Brief="Total Energy Holdup on tray"); |
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| 163 | vL as volume_mol (Brief="Liquid Molar Volume"); |
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| 164 | vV as volume_mol (Brief="Vapour Molar volume"); |
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| 165 | Level as length (Brief="Level of liquid phase"); |
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| 166 | Vol as volume; |
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| 167 | r3 as reaction_mol (Brief="Reaction Rates", DisplayUnit = 'mol/l/s'); |
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| 168 | C(NComp) as conc_mol (Brief="Molar concentration", Lower = -1); |
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[698] | 169 | |
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[721] | 170 | INITIAL |
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| 171 | |
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| 172 | Level = Initial_Level; |
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[735] | 173 | OutletLiquid.T = Initial_Temperature; |
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| 174 | OutletLiquid.z(1:NComp-1) = Initial_Composition(1:NComp-1)/sum(Initial_Composition); |
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[721] | 175 | |
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| 176 | EQUATIONS |
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| 177 | "Molar Concentration" |
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[735] | 178 | OutletLiquid.z = vL * C; |
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[698] | 179 | |
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[721] | 180 | "Reaction" |
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[735] | 181 | r3 = exp(-7150*'K'/OutletLiquid.T)*(4.85e4*C(1)*C(2) - 1.23e4*C(3)*C(4)) * 'l/mol/s'; |
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[698] | 182 | |
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[721] | 183 | "Component Molar Balance" |
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[735] | 184 | diff(M) = InletVapour.F*InletVapour.z - OutletLiquid.F*OutletLiquid.z - OutletVapour.F*OutletVapour.z + stoic*r3*ML*vL; |
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[698] | 185 | |
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[721] | 186 | "Energy Balance" |
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[735] | 187 | diff(E) = InletVapour.F*InletVapour.h - OutletLiquid.F*OutletLiquid.h- OutletVapour.F*OutletVapour.h + InletQ + Hr * r3 * ML*vL; |
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[698] | 188 | |
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[721] | 189 | "Molar Holdup" |
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[735] | 190 | M = ML*OutletLiquid.z + MV*OutletVapour.z; |
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[698] | 191 | |
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[721] | 192 | "Energy Holdup" |
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[735] | 193 | E = ML*OutletLiquid.h + MV*OutletVapour.h - OutletVapour.P*V; |
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[698] | 194 | |
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[721] | 195 | "Mol fraction normalisation" |
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[735] | 196 | sum(OutletLiquid.z)=1.0; |
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[698] | 197 | |
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[721] | 198 | "Liquid Volume" |
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[735] | 199 | vL = PP.LiquidVolume(OutletLiquid.T, OutletLiquid.P, OutletLiquid.z); |
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[721] | 200 | |
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| 201 | "Vapour Volume" |
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[735] | 202 | vV = PP.VapourVolume(OutletVapour.T, OutletVapour.P, OutletVapour.z); |
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[698] | 203 | |
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[721] | 204 | "Thermal Equilibrium" |
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[735] | 205 | OutletLiquid.T = OutletVapour.T; |
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[698] | 206 | |
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[721] | 207 | "Mechanical Equilibrium" |
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[735] | 208 | OutletVapour.P = OutletLiquid.P; |
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[698] | 209 | |
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[721] | 210 | "Geometry Constraint" |
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[698] | 211 | V = ML*vL + MV*vV; |
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| 212 | |
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| 213 | Vol = ML*vL; |
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| 214 | |
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[721] | 215 | "Level of liquid phase" |
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[698] | 216 | Level = ML*vL/Across; |
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| 217 | |
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[721] | 218 | "Chemical Equilibrium" |
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[735] | 219 | PP.LiquidFugacityCoefficient(OutletLiquid.T, OutletLiquid.P, OutletLiquid.z)*OutletLiquid.z = |
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| 220 | PP.VapourFugacityCoefficient(OutletVapour.T, OutletVapour.P, OutletVapour.z)*OutletVapour.z; |
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[698] | 221 | |
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[735] | 222 | sum(OutletLiquid.z)=sum(OutletVapour.z); |
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[698] | 223 | |
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| 224 | end |
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[755] | 225 | |
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[793] | 226 | Model condenser |
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| 227 | |
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| 228 | ATTRIBUTES |
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[755] | 229 | Pallete = true; |
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[793] | 230 | Icon = "icon/Condenser"; |
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[757] | 231 | Brief = "Model of a dynamic condenser with control."; |
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[755] | 232 | Info = |
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[793] | 233 | "== ASSUMPTIONS == |
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[755] | 234 | * perfect mixing of both phases; |
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| 235 | * thermodynamics equilibrium. |
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| 236 | |
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[793] | 237 | == SPECIFY == |
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| 238 | * the InletVapour stream; |
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[755] | 239 | * the outlet flows: OutletVapour.F and OutletLiquid.F; |
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[793] | 240 | * the InletQ (the model requires an energy stream, also you can use a controller for setting the heat duty using the heat_flow model). |
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| 241 | |
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| 242 | == OPTIONAL == |
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| 243 | * the condenser model has three control ports |
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| 244 | ** TI OutletLiquid Temperature Indicator; |
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| 245 | ** PI OutletLiquid Pressure Indicator; |
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| 246 | ** LI Level Indicator of Condenser; |
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| 247 | |
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| 248 | == INITIAL CONDITIONS == |
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[757] | 249 | * Initial_Temperature : the condenser temperature (OutletLiquid.T); |
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[821] | 250 | * Levelpercent_Initial : the condenser liquid level in percent (LI); |
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[757] | 251 | * Initial_Composition : (NoComps) OutletLiquid compositions. |
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[755] | 252 | "; |
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| 253 | |
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| 254 | PARAMETERS |
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[793] | 255 | outer PP as Plugin (Brief = "External Physical Properties", Type="PP"); |
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[757] | 256 | outer NComp as Integer (Brief="Number of Components"); |
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[768] | 257 | |
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| 258 | Mw(NComp) as molweight (Brief = "Component Mol Weight",Hidden=true); |
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[793] | 259 | low_flow as flow_mol (Brief = "Low Flow",Default = 1E-6, Hidden=true); |
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| 260 | zero_flow as flow_mol (Brief = "No Flow",Default = 0, Hidden=true); |
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| 261 | KfConst as area (Brief="Constant for K factor pressure drop", Default = 1, Hidden=true); |
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[768] | 262 | |
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[793] | 263 | VapourFlow as Switcher (Brief="Vapour Flow", Valid = ["on", "off"], Default = "on",Hidden=true); |
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[768] | 264 | |
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[793] | 265 | V as volume (Brief="Condenser total volume"); |
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| 266 | Across as area (Brief="Cross Section Area of condenser"); |
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| 267 | Kfactor as positive (Brief="K factor for pressure drop", Lower = 1E-8, Default = 1E-3); |
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[755] | 268 | |
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[821] | 269 | Levelpercent_Initial as positive (Brief="Initial liquid height in Percent", Default = 0.70); |
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[793] | 270 | Initial_Temperature as temperature (Brief="Initial Temperature of Condenser"); |
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| 271 | Initial_Composition(NComp) as positive (Brief="Initial Liquid Composition", Lower=1E-6); |
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[755] | 272 | |
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| 273 | VARIABLES |
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[757] | 274 | |
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[793] | 275 | in InletVapour as stream (Brief="Vapour inlet stream", PosX=0.13, PosY=0, Symbol="_{in}^{Vapour}"); |
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| 276 | out OutletLiquid as liquid_stream (Brief="Liquid outlet stream", PosX=0.35, PosY=1, Symbol="_{out}^{Liquid}"); |
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| 277 | out OutletVapour as vapour_stream (Brief="Vapour outlet stream", PosX=0.54, PosY=0, Symbol="_{out}^{Vapour}"); |
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| 278 | in InletQ as power (Brief="Heat supplied", Protected = true, PosX=1, PosY=0.08, Symbol="Q_{in}"); |
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[755] | 279 | |
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[793] | 280 | out TI as control_signal (Brief="Temperature Indicator of Condenser", Protected = true, PosX=0.33, PosY=0); |
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| 281 | out LI as control_signal (Brief="Level Indicator of Condenser", Protected = true, PosX=0.43, PosY=0); |
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| 282 | out PI as control_signal (Brief="Pressure Indicator of Condenser", Protected = true, PosX=0.25, PosY=0); |
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[757] | 283 | |
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[793] | 284 | M(NComp) as mol (Brief="Molar Holdup in the tray", Protected = true); |
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| 285 | ML as mol (Brief="Molar liquid holdup", Protected = true); |
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| 286 | MV as mol (Brief="Molar vapour holdup", Protected = true); |
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| 287 | E as energy (Brief="Total Energy Holdup on tray", Protected = true); |
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| 288 | vL as volume_mol (Brief="Liquid Molar Volume", Protected = true); |
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| 289 | vV as volume_mol (Brief="Vapour Molar volume", Protected = true); |
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| 290 | rho as dens_mass (Brief ="Inlet Vapour Mass Density",Hidden=true, Symbol ="\rho"); |
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| 291 | Level as length (Brief="Level of liquid phase", Protected = true); |
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| 292 | Pdrop as press_delta (Brief = "Pressure Drop", DisplayUnit = 'kPa', Symbol ="\Delta P", Protected=true); |
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[755] | 293 | |
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[768] | 294 | SET |
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| 295 | |
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| 296 | Mw = PP.MolecularWeight(); |
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[793] | 297 | low_flow = 1E-6 * 'kmol/h'; |
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| 298 | zero_flow = 0 * 'kmol/h'; |
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| 299 | KfConst = 1*'m^2'; |
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[768] | 300 | |
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[755] | 301 | INITIAL |
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| 302 | |
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[821] | 303 | "Initial level Percent" |
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| 304 | LI = Levelpercent_Initial; |
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[757] | 305 | |
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| 306 | "Initial Temperature" |
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[793] | 307 | OutletLiquid.T = Initial_Temperature; |
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[757] | 308 | |
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| 309 | "Initial Composition" |
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[793] | 310 | OutletLiquid.z(1:NComp-1) = Initial_Composition(1:NComp-1)/sum(Initial_Composition); |
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[768] | 311 | |
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[755] | 312 | EQUATIONS |
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[768] | 313 | |
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| 314 | switch VapourFlow |
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| 315 | |
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[793] | 316 | case "on": |
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| 317 | InletVapour.F*sum(Mw*InletVapour.z) = Kfactor *sqrt(Pdrop*rho)*KfConst; |
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[768] | 318 | |
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[793] | 319 | when InletVapour.F < low_flow switchto "off"; |
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[768] | 320 | |
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[793] | 321 | case "off": |
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| 322 | InletVapour.F = zero_flow; |
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[768] | 323 | |
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| 324 | when InletVapour.P > OutletLiquid.P switchto "on"; |
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| 325 | |
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| 326 | end |
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| 327 | |
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[755] | 328 | "Component Molar Balance" |
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| 329 | diff(M) = InletVapour.F*InletVapour.z - OutletLiquid.F*OutletLiquid.z- OutletVapour.F*OutletVapour.z; |
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| 330 | |
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| 331 | "Energy Balance" |
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| 332 | diff(E) = InletVapour.F*InletVapour.h - OutletLiquid.F*OutletLiquid.h- OutletVapour.F*OutletVapour.h + InletQ; |
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| 333 | |
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| 334 | "Molar Holdup" |
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| 335 | M = ML*OutletLiquid.z + MV*OutletVapour.z; |
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| 336 | |
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| 337 | "Energy Holdup" |
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| 338 | E = ML*OutletLiquid.h + MV*OutletVapour.h - OutletVapour.P*V; |
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| 339 | |
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| 340 | "Mol fraction normalisation" |
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| 341 | sum(OutletLiquid.z)=1.0; |
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[767] | 342 | |
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| 343 | "Mol fraction Constraint" |
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[755] | 344 | sum(OutletLiquid.z)=sum(OutletVapour.z); |
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| 345 | |
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| 346 | "Liquid Volume" |
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| 347 | vL = PP.LiquidVolume(OutletLiquid.T, OutletLiquid.P, OutletLiquid.z); |
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| 348 | |
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| 349 | "Vapour Volume" |
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| 350 | vV = PP.VapourVolume(OutletVapour.T, OutletVapour.P, OutletVapour.z); |
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| 351 | |
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[768] | 352 | "Inlet Vapour Density" |
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| 353 | rho = PP.VapourDensity(InletVapour.T, InletVapour.P, InletVapour.z); |
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| 354 | |
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[755] | 355 | "Chemical Equilibrium" |
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| 356 | PP.LiquidFugacityCoefficient(OutletLiquid.T, OutletLiquid.P, OutletLiquid.z)*OutletLiquid.z = |
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| 357 | PP.VapourFugacityCoefficient(OutletVapour.T, OutletVapour.P, OutletVapour.z)*OutletVapour.z; |
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| 358 | |
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| 359 | "Thermal Equilibrium" |
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| 360 | OutletLiquid.T = OutletVapour.T; |
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| 361 | |
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| 362 | "Mechanical Equilibrium" |
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| 363 | OutletVapour.P = OutletLiquid.P; |
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| 364 | |
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[768] | 365 | "Pressure Drop" |
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| 366 | OutletLiquid.P = InletVapour.P - Pdrop; |
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| 367 | |
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[755] | 368 | "Geometry Constraint" |
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| 369 | V = ML*vL + MV*vV; |
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| 370 | |
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| 371 | "Level of liquid phase" |
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| 372 | Level = ML*vL/Across; |
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| 373 | |
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[757] | 374 | "Temperature indicator" |
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[793] | 375 | TI * 'K' = OutletLiquid.T; |
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[757] | 376 | |
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[767] | 377 | "Pressure indicator" |
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[793] | 378 | PI * 'atm' = OutletLiquid.P; |
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[767] | 379 | |
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[757] | 380 | "Level indicator" |
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[793] | 381 | LI*V = Level*Across; |
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[757] | 382 | |
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[755] | 383 | end |
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