[302] | 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: Rafael de P. Soares and Paula B. Staudt |
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| 17 | * $Id: pfr.mso 325 2007-07-29 00:41:04Z arge $ |
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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 pfr |
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| 23 | |
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| 24 | ATTRIBUTES |
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| 25 | Pallete = true; |
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| 26 | Brief = "Model of a Generic PFR with constant mass holdup"; |
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| 27 | Icon = "icon/pfr"; |
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| 28 | Info = " |
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| 29 | Requires the information of: |
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| 30 | * Reaction values |
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| 31 | * Heat of reaction |
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| 32 | * Pressure profile |
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| 33 | "; |
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| 34 | |
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| 35 | PARAMETERS |
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| 36 | |
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| 37 | outer PP as Plugin (Brief = "External Physical Properties", Type="PP"); |
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| 38 | outer NComp as Integer (Brief="Number of components"); |
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| 39 | NReac as Integer (Brief="Number of reactions"); |
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| 40 | stoic(NComp, NReac) as Real (Brief = "Stoichiometric Matrix"); |
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| 41 | NDisc as Integer (Brief="Number of points of discretization", Default=10); |
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| 42 | Mw(NComp) as molweight (Brief="Component Mol Weight"); |
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| 43 | L as length (Brief="Reactor Length"); |
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| 44 | Across as area (Brief="Cross section area"); |
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| 45 | |
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| 46 | SET |
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| 47 | |
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| 48 | Mw = PP.MolecularWeight(); |
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| 49 | |
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| 50 | VARIABLES |
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| 51 | |
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[325] | 52 | in Inlet as stream (Brief = "Inlet Stream", PosX=0, PosY=0.5076); |
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| 53 | out Outlet as stream (Brief = "Outlet Stream", PosX=1, PosY=0.5236); |
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[302] | 54 | |
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| 55 | str(NDisc+1) as streamPH; |
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| 56 | vel(NDisc+1) as velocity; |
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| 57 | vol(NDisc+1) as vol_mol; |
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| 58 | rho(NDisc+1) as dens_mass; |
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| 59 | |
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| 60 | q(NDisc) as heat_rate; |
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| 61 | M(NComp, NDisc) as mol (Brief = "Molar holdup"); |
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| 62 | Mt(NDisc) as mol (Brief = "Molar holdup"); |
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| 63 | C(NComp, NDisc) as conc_mol (Brief="Components concentration", Lower=-1e-6); |
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| 64 | E(NDisc) as energy (Brief="Total Energy Holdup on element"); |
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| 65 | r(NReac, NDisc) as reaction_mol; |
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| 66 | Hr(NReac, NDisc) as heat_reaction; |
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| 67 | |
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| 68 | EQUATIONS |
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| 69 | |
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| 70 | "Inlet boundary" |
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| 71 | str(1).F = Inlet.F; |
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| 72 | str(1).T = Inlet.T; |
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| 73 | str(1).P = Inlet.P; |
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| 74 | str(1).z = Inlet.z; |
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| 75 | |
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| 76 | "Outlet boundary" |
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| 77 | Outlet.F = str(NDisc+1).F; |
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| 78 | Outlet.T = str(NDisc+1).T; |
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| 79 | Outlet.P = str(NDisc+1).P; |
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| 80 | Outlet.z = str(NDisc+1).z; |
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| 81 | Outlet.h = str(NDisc+1).h; |
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| 82 | Outlet.v = str(NDisc+1).v; |
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| 83 | |
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| 84 | for z in [1:NDisc] |
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| 85 | for c in [1:NComp-1] |
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| 86 | "Component Molar Balance" |
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| 87 | diff(M(c,z)) = (str(z).F*str(z).z(c) - str(z+1).F*str(z+1).z(c)) |
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| 88 | + sum(stoic(c,:)*r(:, z)) * Across*L/NDisc; |
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| 89 | end |
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| 90 | |
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| 91 | "Energy Balance" |
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| 92 | diff(E(z)) = str(z).F*str(z).h - str(z+1).F*str(z+1).h + |
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| 93 | sum(Hr(:,z)*r(:,z)) * Across*L/NDisc - q(z); |
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| 94 | |
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| 95 | "Energy Holdup" |
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| 96 | E(z) = Mt(z)*str(z+1).h - str(z+1).P*Across*L/NDisc; |
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| 97 | |
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| 98 | "mass flow is considered constant" |
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| 99 | str(z+1).F*vol(z+1) = str(z).F*vol(z); # FIXME: is this correct? No (constant velocity: only for equimolar) |
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| 100 | #rho(z+1)*vel(z+1) = rho(z)*vel(z); # FIXME: this is correct! But does not converge. |
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| 101 | |
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| 102 | "Molar concentration" |
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| 103 | C(:,z) * Across*L/NDisc = M(:,z); |
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| 104 | |
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| 105 | "Sum of M" |
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| 106 | Mt(z) = sum(M(:,z)); |
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| 107 | |
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| 108 | "Geometrical constraint" |
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| 109 | Across*L/NDisc = Mt(z) * vol(z); |
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| 110 | |
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| 111 | "Molar fraction" |
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| 112 | str(z+1).z * Mt(z) = M(:,z); |
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| 113 | end |
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| 114 | |
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| 115 | for z in [1:NDisc+1] |
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| 116 | "Specific Volume" |
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| 117 | vol(z) = PP.VapourVolume(str(z).T, str(z).P, str(z).z); |
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| 118 | |
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| 119 | "Specific Mass" |
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| 120 | rho(z) = PP.VapourDensity(str(z).T, str(z).P, str(z).z); |
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| 121 | |
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| 122 | "Velocity" |
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| 123 | vel(z)*Across = str(z).F*vol(z); |
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| 124 | end |
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| 125 | end |
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