[420] | 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 | * Author: Gerson Balbueno Bicca |
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| 16 | * $Id: PHE.mso 250 2007-04-27 16:32:02Z bicca $ |
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| 17 | *------------------------------------------------------------------*# |
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| 18 | using "HEX_Engine"; |
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| 19 | |
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| 20 | Model PHE |
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| 21 | |
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| 22 | ATTRIBUTES |
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| 23 | Icon = "icon/phe"; |
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| 24 | Pallete = true; |
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| 25 | Brief = "Shortcut model for plate and Frame heat exchanger."; |
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| 26 | Info = |
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| 27 | "Model of a gasketed plate heat exchanger. |
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| 28 | The heat transfer and pressure loss calculations are based on Kumar [1] work. |
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| 29 | The following assumptions are considered in order to derive the mathematical model [2]: |
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| 30 | |
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| 31 | == Assumptions == |
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| 32 | * Steady-State operation; |
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| 33 | * No phase changes; |
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| 34 | * No heat loss to the surroundings. |
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| 35 | * Uniform distribution of flow through the channels of a pass. |
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| 36 | |
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| 37 | == Specify == |
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| 38 | * The Inlet streams: Hot and Cold; |
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| 39 | |
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| 40 | == Setting The PHE Parameters == |
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| 41 | *ChevronAngle |
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| 42 | *Nplates |
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| 43 | *NpassHot |
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| 44 | *NpassCold |
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| 45 | *Dports |
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| 46 | *PhiFactor |
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| 47 | *Lv |
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| 48 | *Lw |
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| 49 | *pitch |
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| 50 | *pt |
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| 51 | *Kwall |
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| 52 | *Rfc |
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| 53 | *Rfh |
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| 54 | |
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| 55 | == Setting The PHE Option Parameters == |
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| 56 | *SideOne: cold or hot |
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| 57 | |
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| 58 | == References == |
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| 59 | |
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| 60 | [1] E.A.D. Saunders, Heat Exchangers: Selection, Design and |
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| 61 | Construction, Longman, Harlow, 1988. |
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| 62 | |
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| 63 | [2] J.A.W. Gut, J.M. Pinto, Modeling of plate heat exchangers |
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| 64 | with generalized configurations, Int. J. Heat Mass Transfer |
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| 65 | 46 (14) (2003) 2571\2585. |
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| 66 | "; |
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| 67 | |
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| 68 | PARAMETERS |
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| 69 | |
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| 70 | outer PP as Plugin (Brief="External Physical Properties", Type="PP"); |
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| 71 | outer NComp as Integer (Brief="Number of Chemical Components"); |
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| 72 | Pi as constant (Brief="Pi Number",Default=3.14159265, Symbol = "\pi"); |
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| 73 | N1 as Integer (Brief="Auxiliar Constant",Default = 15); |
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| 74 | N2 as Integer (Brief="Auxiliar Constant",Default = 14); |
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| 75 | Kp1(N1) as constant (Brief="First constant in Kumar calculation for Pressure Drop"); |
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| 76 | Kp2(N1) as constant (Brief="Second constant in Kumar calculation for Pressure Drop"); |
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| 77 | Kc1(N2) as constant (Brief="First constant in Kumar calculation for Heat Transfer"); |
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| 78 | Kc2(N2) as constant (Brief="Second constant Kumar calculation for Heat Transfer"); |
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| 79 | M(NComp) as molweight (Brief="Component Mol Weight"); |
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| 80 | |
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| 81 | ChevronAngle as Switcher (Brief="Chevron Corrugation Inclination Angle in Degrees ",Valid=["A30_Deg","A45_Deg","A50_Deg","A60_Deg","A65_Deg"],Default="A30_Deg"); |
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| 82 | SideOne as Switcher (Brief="Fluid Alocation in the Side I - (The odd channels)",Valid=["hot","cold"],Default="hot"); |
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| 83 | Nchannels as Integer (Brief="Total Number of Channels in The Whole Heat Exchanger"); |
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| 84 | Nplates as Integer (Brief="Total Number of Plates in The Whole Heat Exchanger",Default=25, Symbol ="N_{plates}"); |
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| 85 | NpassHot as Integer (Brief="Number of Passes for Hot Side", Symbol ="Npasshot"); |
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| 86 | NpassCold as Integer (Brief="Number of Passes for Cold Side", Symbol ="Npasscold"); |
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| 87 | Dports as length (Brief="Ports Diameter",Lower=1e-6, Symbol ="D_{ports}"); |
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| 88 | Atotal as area (Brief="Total Effective Area",Lower=1e-6, Symbol ="A_{total}"); |
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| 89 | Aports as area (Brief="Port Opening Area of Plate",Lower=1e-6, Symbol ="A_{ports}"); |
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| 90 | Achannel as area (Brief="Cross-Sectional Area for Channel Flow",Lower=1e-6, Symbol ="A_{channel}"); |
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| 91 | Dh as length (Brief="Equivalent Diameter of Channel",Lower=1e-6); |
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| 92 | Depth as length (Brief="Corrugation Depth",Lower=1e-6); |
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| 93 | PhiFactor as Real (Brief="Enlargement Factor",Lower=1e-6, Symbol ="\phi"); |
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| 94 | Lp as length (Brief="Plate Vertical Distance between Port Centers",Lower=0.1); |
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| 95 | Lpack as length (Brief="Compact Plate Pack Length",Lower=0.1); |
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| 96 | Lv as length (Brief="Vertical Ports Distance",Lower=0.1); |
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| 97 | Lh as length (Brief="Plate Horizontal Distance between Port Centers",Lower=0.1); |
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| 98 | Lw as length (Brief="Plate Width",Lower=0.1); |
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| 99 | pitch as length (Brief="Plate Pitch",Lower=0.1); |
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| 100 | pt as length (Brief="Plate Thickness",Lower=0.1); |
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| 101 | Kwall as conductivity (Brief="Plate Thermal Conductivity",Default=1.0, Symbol ="K_{wall}"); |
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| 102 | Rfh as positive (Brief="Hot Side Fouling Resistance",Unit='m^2*K/kW',Default=1e-6,Lower=0); |
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| 103 | Rfc as positive (Brief="Cold Side Fouling Resistance",Unit='m^2*K/kW',Default=1e-6,Lower=0); |
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| 104 | |
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| 105 | VARIABLES |
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| 106 | |
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| 107 | in InletHot as stream (Brief="Inlet Hot Stream", PosX=0, PosY=0.75, Symbol="^{inHot}"); |
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| 108 | in InletCold as stream (Brief="Inlet Cold Stream", PosX=0, PosY=0.25, Symbol="^{inCold}"); |
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| 109 | out OutletHot as streamPH (Brief="Outlet Hot Stream", PosX=1, PosY=0.25, Symbol="^{outHot}"); |
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| 110 | out OutletCold as streamPH (Brief="Outlet Cold Stream", PosX=1, PosY=0.75, Symbol="^{outCold}"); |
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| 111 | |
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| 112 | HotSide as Main_PHE (Brief="Plate Heat Exchanger Hot Side", Symbol="_{hot}"); |
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| 113 | ColdSide as Main_PHE (Brief="Plate Heat Exchanger Cold Side", Symbol="_{cold}"); |
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| 114 | Thermal as Thermal_PHE (Brief="Thermal Results", Symbol = " "); |
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| 115 | |
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| 116 | SET |
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| 117 | #"Vector Length of constants for Kumar's calculating Pressure Drop" |
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| 118 | N1 = 15; |
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| 119 | |
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| 120 | #"Vector Length of constants for Kumar's calculating Heat Transfer" |
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| 121 | N2 = 14; |
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| 122 | |
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| 123 | #"First constant for Kumar's calculating Pressure Drop" |
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| 124 | Kp1 = [50,19.40,2.990,47,18.290,1.441,34,11.250,0.772,24,3.240,0.760,24,2.80,0.639]; |
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| 125 | |
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| 126 | #"Second constant for Kumar's calculating Pressure Drop" |
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| 127 | Kp2 = [1,0.589,0.183,1,0.652,0.206,1,0.631,0.161,1,0.457,0.215,1,0.451,0.213]; |
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| 128 | |
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| 129 | #"First constant for Kumar's calculating Heat Transfer" |
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| 130 | Kc1 = [0.718,0.348,0.718,0.400,0.300,0.630,0.291,0.130,0.562,0.306,0.108,0.562,0.331,0.087]; |
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| 131 | |
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| 132 | #"Second constant for Kumar's calculating Heat Transfer" |
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| 133 | Kc2 = [0.349,0.663,0.349,0.598,0.663,0.333,0.591,0.732,0.326,0.529,0.703,0.326,0.503,0.718]; |
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| 134 | |
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| 135 | #"Component Molecular Weight" |
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| 136 | M = PP.MolecularWeight(); |
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| 137 | |
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| 138 | #"Pi Number" |
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| 139 | Pi = 3.14159265; |
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| 140 | |
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| 141 | #"Plate Vertical Distance between Port Centers" |
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| 142 | Lp = Lv - Dports; |
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| 143 | |
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| 144 | #"Corrugation Depth" |
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| 145 | Depth=pitch-pt; |
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| 146 | |
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| 147 | #"Plate Horizontal Distance between Port Centers" |
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| 148 | Lh=Lw-Dports; |
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| 149 | |
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| 150 | #"Hydraulic Diameter" |
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| 151 | Dh=2*Depth/PhiFactor; |
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| 152 | |
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| 153 | #"Ports Area" |
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| 154 | Aports=0.25*Pi*Dports*Dports; |
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| 155 | |
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| 156 | #"Channel Area" |
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| 157 | Achannel=Depth*Lw; |
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| 158 | |
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| 159 | #"Pack Length" |
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| 160 | Lpack=Depth*(Nplates-1)+Nplates*pt; |
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| 161 | |
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| 162 | #"Total Number of Channels" |
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| 163 | Nchannels = Nplates -1; |
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| 164 | |
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| 165 | #"Exchange Surface Area" |
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| 166 | Atotal =(Nplates-2)*Lw*Lp*PhiFactor; |
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| 167 | |
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| 168 | EQUATIONS |
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| 169 | |
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| 170 | "Hot Stream Average Temperature" |
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| 171 | HotSide.Properties.Average.T = 0.5*InletHot.T + 0.5*OutletHot.T; |
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| 172 | |
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| 173 | "Cold Stream Average Temperature" |
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| 174 | ColdSide.Properties.Average.T = 0.5*InletCold.T + 0.5*OutletCold.T; |
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| 175 | |
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| 176 | "Hot Stream Average Pressure" |
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| 177 | HotSide.Properties.Average.P = 0.5*InletHot.P+0.5*OutletHot.P; |
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| 178 | |
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| 179 | "Cold Stream Average Pressure" |
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| 180 | ColdSide.Properties.Average.P = 0.5*InletCold.P+0.5*OutletCold.P; |
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| 181 | |
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| 182 | "Cold Stream Wall Temperature" |
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| 183 | ColdSide.Properties.Wall.Twall = 0.5*HotSide.Properties.Average.T + 0.5*ColdSide.Properties.Average.T; |
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| 184 | |
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| 185 | "Hot Stream Wall Temperature" |
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| 186 | HotSide.Properties.Wall.Twall = 0.5*HotSide.Properties.Average.T + 0.5*ColdSide.Properties.Average.T; |
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| 187 | |
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| 188 | "Hot Stream Average Molecular Weight" |
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| 189 | HotSide.Properties.Average.Mw = sum(M*InletHot.z); |
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| 190 | |
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| 191 | "Cold Stream Average Molecular Weight" |
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| 192 | ColdSide.Properties.Average.Mw = sum(M*InletCold.z); |
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| 193 | |
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| 194 | if InletCold.v equal 0 |
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| 195 | |
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| 196 | then |
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| 197 | |
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| 198 | "Average Heat Capacity Cold Stream" |
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| 199 | ColdSide.Properties.Average.Cp = PP.LiquidCp(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 200 | |
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| 201 | "Average Mass Density Cold Stream" |
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| 202 | ColdSide.Properties.Average.rho = PP.LiquidDensity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 203 | |
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| 204 | "Inlet Mass Density Cold Stream" |
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| 205 | ColdSide.Properties.Inlet.rho = PP.LiquidDensity(InletCold.T,InletCold.P,InletCold.z); |
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| 206 | |
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| 207 | "Outlet Mass Density Cold Stream" |
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| 208 | ColdSide.Properties.Outlet.rho = PP.LiquidDensity(OutletCold.T,OutletCold.P,OutletCold.z); |
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| 209 | |
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| 210 | "Average Viscosity Cold Stream" |
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| 211 | ColdSide.Properties.Average.Mu = PP.LiquidViscosity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 212 | |
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| 213 | "Average Conductivity Cold Stream" |
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| 214 | ColdSide.Properties.Average.K = PP.LiquidThermalConductivity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 215 | |
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| 216 | "Viscosity Cold Stream at wall temperature" |
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| 217 | ColdSide.Properties.Wall.Mu = PP.LiquidViscosity(ColdSide.Properties.Wall.Twall,ColdSide.Properties.Average.P,InletCold.z); |
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| 218 | |
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| 219 | else |
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| 220 | |
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| 221 | "Average Heat Capacity ColdStream" |
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| 222 | ColdSide.Properties.Average.Cp = PP.VapourCp(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 223 | |
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| 224 | "Average Mass Density Cold Stream" |
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| 225 | ColdSide.Properties.Average.rho = PP.VapourDensity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 226 | |
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| 227 | "Inlet Mass Density Cold Stream" |
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| 228 | ColdSide.Properties.Inlet.rho = PP.VapourDensity(InletCold.T,InletCold.P,InletCold.z); |
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| 229 | |
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| 230 | "Outlet Mass Density Cold Stream" |
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| 231 | ColdSide.Properties.Outlet.rho = PP.VapourDensity(OutletCold.T,OutletCold.P,OutletCold.z); |
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| 232 | |
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| 233 | "Average Viscosity Cold Stream" |
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| 234 | ColdSide.Properties.Average.Mu = PP.VapourViscosity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 235 | |
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| 236 | "Average Conductivity Cold Stream" |
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| 237 | ColdSide.Properties.Average.K = PP.VapourThermalConductivity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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| 238 | |
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| 239 | "Viscosity Cold Stream at wall temperature" |
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| 240 | ColdSide.Properties.Wall.Mu = PP.VapourViscosity(ColdSide.Properties.Wall.Twall,ColdSide.Properties.Average.P,InletCold.z); |
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| 241 | |
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| 242 | end |
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| 243 | |
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| 244 | if InletHot.v equal 0 |
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| 245 | |
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| 246 | then |
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| 247 | |
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| 248 | "Average Heat Capacity Hot Stream" |
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| 249 | HotSide.Properties.Average.Cp = PP.LiquidCp(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 250 | |
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| 251 | "Average Mass Density Hot Stream" |
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| 252 | HotSide.Properties.Average.rho = PP.LiquidDensity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 253 | |
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| 254 | "Inlet Mass Density Hot Stream" |
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| 255 | HotSide.Properties.Inlet.rho = PP.LiquidDensity(InletHot.T,InletHot.P,InletHot.z); |
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| 256 | |
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| 257 | "Outlet Mass Density Hot Stream" |
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| 258 | HotSide.Properties.Outlet.rho = PP.LiquidDensity(OutletHot.T,OutletHot.P,OutletHot.z); |
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| 259 | |
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| 260 | "Average Viscosity Hot Stream" |
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| 261 | HotSide.Properties.Average.Mu = PP.LiquidViscosity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 262 | |
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| 263 | "Average Conductivity Hot Stream" |
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| 264 | HotSide.Properties.Average.K = PP.LiquidThermalConductivity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 265 | |
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| 266 | "Viscosity Hot Stream at wall temperature" |
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| 267 | HotSide.Properties.Wall.Mu = PP.LiquidViscosity(HotSide.Properties.Wall.Twall,HotSide.Properties.Average.P,InletHot.z); |
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| 268 | |
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| 269 | |
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| 270 | else |
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| 271 | |
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| 272 | "Average Heat Capacity Hot Stream" |
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| 273 | HotSide.Properties.Average.Cp = PP.VapourCp(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 274 | |
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| 275 | "Average Mass Density Hot Stream" |
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| 276 | HotSide.Properties.Average.rho = PP.VapourDensity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 277 | |
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| 278 | "Inlet Mass Density Hot Stream" |
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| 279 | HotSide.Properties.Inlet.rho = PP.VapourDensity(InletHot.T,InletHot.P,InletHot.z); |
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| 280 | |
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| 281 | "Outlet Mass Density Hot Stream" |
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| 282 | HotSide.Properties.Outlet.rho = PP.VapourDensity(OutletHot.T,OutletHot.P,OutletHot.z); |
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| 283 | |
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| 284 | "Average Viscosity Hot Stream" |
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| 285 | HotSide.Properties.Average.Mu = PP.VapourViscosity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 286 | |
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| 287 | "Average Conductivity Hot Stream" |
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| 288 | HotSide.Properties.Average.K = PP.VapourThermalConductivity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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| 289 | |
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| 290 | "Viscosity Hot Stream at wall temperature" |
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| 291 | HotSide.Properties.Wall.Mu = PP.VapourViscosity(HotSide.Properties.Wall.Twall,HotSide.Properties.Average.P,InletHot.z); |
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| 292 | |
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| 293 | end |
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| 294 | |
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| 295 | "Energy Balance Hot Stream" |
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| 296 | Thermal.Q = InletHot.F*(InletHot.h-OutletHot.h); |
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| 297 | |
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| 298 | "Energy Balance Cold Stream" |
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| 299 | Thermal.Q = InletCold.F*(OutletCold.h - InletCold.h); |
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| 300 | |
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| 301 | "Flow Mass Inlet Cold Stream" |
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| 302 | ColdSide.Properties.Inlet.Fw = sum(M*InletCold.z)*InletCold.F; |
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| 303 | |
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| 304 | "Flow Mass Outlet Cold Stream" |
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| 305 | ColdSide.Properties.Outlet.Fw = sum(M*OutletCold.z)*OutletCold.F; |
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| 306 | |
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| 307 | "Flow Mass Inlet Hot Stream" |
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| 308 | HotSide.Properties.Inlet.Fw = sum(M*InletHot.z)*InletHot.F; |
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| 309 | |
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| 310 | "Flow Mass Outlet Hot Stream" |
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| 311 | HotSide.Properties.Outlet.Fw = sum(M*OutletHot.z)*OutletHot.F; |
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| 312 | |
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| 313 | "Molar Balance Hot Stream" |
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| 314 | OutletHot.F = InletHot.F; |
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| 315 | |
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| 316 | "Molar Balance Cold Stream" |
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| 317 | OutletCold.F = InletCold.F; |
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| 318 | |
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| 319 | "Hot Stream Molar Fraction Constraint" |
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| 320 | OutletHot.z=InletHot.z; |
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| 321 | |
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| 322 | "Cold Stream Molar Fraction Constraint" |
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| 323 | OutletCold.z=InletCold.z; |
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| 324 | |
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| 325 | switch SideOne |
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| 326 | |
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| 327 | case "cold": |
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| 328 | |
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| 329 | "Total Number of Passages Cold Side" |
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| 330 | ColdSide.PressureDrop.Npassage = (2*Nchannels+1+(-1)^(Nchannels+1))/(4*NpassCold); |
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| 331 | |
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| 332 | "Total Number of Passages Hot Side" |
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| 333 | HotSide.PressureDrop.Npassage = (2*Nchannels-1+(-1)^(Nchannels))/(4*NpassHot); |
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| 334 | |
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| 335 | case "hot": |
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| 336 | |
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| 337 | "Total Number of Passages Cold Side" |
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| 338 | HotSide.PressureDrop.Npassage = (2*Nchannels+1+(-1)^(Nchannels+1))/(4*NpassHot); |
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| 339 | |
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| 340 | "Total Number of Passages Hot Side" |
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| 341 | ColdSide.PressureDrop.Npassage = (2*Nchannels-1+(-1)^(Nchannels))/(4*NpassCold); |
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| 342 | |
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| 343 | end |
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| 344 | |
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| 345 | "Hot Stream Mass Flux in the Channel" |
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| 346 | HotSide.HeatTransfer.Gchannel=HotSide.Properties.Inlet.Fw/(HotSide.PressureDrop.Npassage*Achannel); |
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| 347 | |
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| 348 | "Hot Stream Mass Flux in the Ports" |
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| 349 | HotSide.HeatTransfer.Gports=HotSide.Properties.Inlet.Fw/Aports; |
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| 350 | |
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| 351 | "Cold Stream Mass Flux in the Ports" |
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| 352 | ColdSide.HeatTransfer.Gports=ColdSide.Properties.Inlet.Fw/Aports; |
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| 353 | |
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| 354 | "Cold Stream Mass Flux in the Channel" |
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| 355 | ColdSide.HeatTransfer.Gchannel=ColdSide.Properties.Inlet.Fw/(ColdSide.PressureDrop.Npassage*Achannel); |
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| 356 | |
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| 357 | "Hot Stream Pressure Drop in Ports" |
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| 358 | HotSide.PressureDrop.DPports =1.5*NpassHot*HotSide.HeatTransfer.Gports^2/(2*HotSide.Properties.Average.rho); |
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| 359 | |
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| 360 | "Cold Stream Pressure Drop in Ports" |
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| 361 | ColdSide.PressureDrop.DPports =1.5*NpassCold*ColdSide.HeatTransfer.Gports^2/(2*ColdSide.Properties.Average.rho); |
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| 362 | |
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| 363 | "Hot Stream Pressure Drop in Channels" |
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| 364 | HotSide.PressureDrop.DPchannel =2*HotSide.PressureDrop.fi*NpassHot*Lv*HotSide.HeatTransfer.Gchannel^2/(HotSide.Properties.Average.rho*Dh*HotSide.HeatTransfer.Phi^0.17); |
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| 365 | |
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| 366 | "Cold Stream Pressure Drop in Channels" |
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| 367 | ColdSide.PressureDrop.DPchannel =2*ColdSide.PressureDrop.fi*NpassCold*Lv*ColdSide.HeatTransfer.Gchannel^2/(ColdSide.Properties.Average.rho*Dh*ColdSide.HeatTransfer.Phi^0.17); |
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| 368 | |
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| 369 | "Hot Stream Total Pressure Drop" |
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| 370 | HotSide.PressureDrop.Pdrop =HotSide.PressureDrop.DPchannel+HotSide.PressureDrop.DPports; |
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| 371 | |
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| 372 | "Cold Stream Total Pressure Drop" |
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| 373 | ColdSide.PressureDrop.Pdrop =ColdSide.PressureDrop.DPchannel+ColdSide.PressureDrop.DPports; |
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| 374 | |
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| 375 | switch ChevronAngle #Pressure Drop Friction Factor According to kumar's (1984) |
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| 376 | |
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| 377 | case "A30_Deg": # ChevronAngle <= 30 |
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| 378 | |
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| 379 | if HotSide.HeatTransfer.Re < 10 |
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| 380 | then |
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| 381 | HotSide.PressureDrop.fi = Kp1(1)/HotSide.HeatTransfer.Re^Kp2(1); |
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| 382 | ColdSide.PressureDrop.fi = Kp1(1)/ColdSide.HeatTransfer.Re^Kp2(1); |
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| 383 | else |
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| 384 | if HotSide.HeatTransfer.Re < 100 |
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| 385 | then |
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| 386 | HotSide.PressureDrop.fi = Kp1(2)/HotSide.HeatTransfer.Re^Kp2(2); |
---|
| 387 | ColdSide.PressureDrop.fi = Kp1(2)/ColdSide.HeatTransfer.Re^Kp2(2); |
---|
| 388 | else |
---|
| 389 | HotSide.PressureDrop.fi = Kp1(3)/HotSide.HeatTransfer.Re^Kp2(3); |
---|
| 390 | ColdSide.PressureDrop.fi = Kp1(3)/ColdSide.HeatTransfer.Re^Kp2(3); |
---|
| 391 | end |
---|
| 392 | |
---|
| 393 | end |
---|
| 394 | |
---|
| 395 | case "A45_Deg": |
---|
| 396 | |
---|
| 397 | if HotSide.HeatTransfer.Re < 15 |
---|
| 398 | then |
---|
| 399 | HotSide.PressureDrop.fi = Kp1(4)/HotSide.HeatTransfer.Re^Kp2(4); |
---|
| 400 | ColdSide.PressureDrop.fi = Kp1(4)/ColdSide.HeatTransfer.Re^Kp2(4); |
---|
| 401 | else |
---|
| 402 | if HotSide.HeatTransfer.Re < 300 |
---|
| 403 | then |
---|
| 404 | HotSide.PressureDrop.fi = Kp1(5)/HotSide.HeatTransfer.Re^Kp2(5); |
---|
| 405 | ColdSide.PressureDrop.fi = Kp1(5)/ColdSide.HeatTransfer.Re^Kp2(5); |
---|
| 406 | else |
---|
| 407 | HotSide.PressureDrop.fi = Kp1(6)/HotSide.HeatTransfer.Re^Kp2(6); |
---|
| 408 | ColdSide.PressureDrop.fi = Kp1(6)/ColdSide.HeatTransfer.Re^Kp2(6); |
---|
| 409 | end |
---|
| 410 | |
---|
| 411 | end |
---|
| 412 | |
---|
| 413 | case "A50_Deg": |
---|
| 414 | |
---|
| 415 | if HotSide.HeatTransfer.Re < 20 |
---|
| 416 | then |
---|
| 417 | HotSide.PressureDrop.fi = Kp1(7)/HotSide.HeatTransfer.Re^Kp2(7); |
---|
| 418 | ColdSide.PressureDrop.fi = Kp1(7)/ColdSide.HeatTransfer.Re^Kp2(7); |
---|
| 419 | else |
---|
| 420 | if HotSide.HeatTransfer.Re < 300 |
---|
| 421 | then |
---|
| 422 | HotSide.PressureDrop.fi = Kp1(8)/HotSide.HeatTransfer.Re^Kp2(8); |
---|
| 423 | ColdSide.PressureDrop.fi = Kp1(8)/ColdSide.HeatTransfer.Re^Kp2(8); |
---|
| 424 | else |
---|
| 425 | HotSide.PressureDrop.fi = Kp1(9)/HotSide.HeatTransfer.Re^Kp2(9); |
---|
| 426 | ColdSide.PressureDrop.fi = Kp1(9)/ColdSide.HeatTransfer.Re^Kp2(9); |
---|
| 427 | end |
---|
| 428 | |
---|
| 429 | end |
---|
| 430 | |
---|
| 431 | case "A60_Deg": |
---|
| 432 | |
---|
| 433 | if HotSide.HeatTransfer.Re < 40 |
---|
| 434 | then |
---|
| 435 | HotSide.PressureDrop.fi = Kp1(10)/HotSide.HeatTransfer.Re^Kp2(10); |
---|
| 436 | ColdSide.PressureDrop.fi = Kp1(10)/ColdSide.HeatTransfer.Re^Kp2(10); |
---|
| 437 | else |
---|
| 438 | if HotSide.HeatTransfer.Re < 400 |
---|
| 439 | then |
---|
| 440 | HotSide.PressureDrop.fi = Kp1(11)/HotSide.HeatTransfer.Re^Kp2(11); |
---|
| 441 | ColdSide.PressureDrop.fi = Kp1(11)/ColdSide.HeatTransfer.Re^Kp2(11); |
---|
| 442 | else |
---|
| 443 | HotSide.PressureDrop.fi = Kp1(12)/HotSide.HeatTransfer.Re^Kp2(12); |
---|
| 444 | ColdSide.PressureDrop.fi = Kp1(12)/ColdSide.HeatTransfer.Re^Kp2(12); |
---|
| 445 | end |
---|
| 446 | |
---|
| 447 | end |
---|
| 448 | |
---|
| 449 | case "A65_Deg": # ChevronAngle >= 65 |
---|
| 450 | |
---|
| 451 | if HotSide.HeatTransfer.Re < 50 |
---|
| 452 | then |
---|
| 453 | HotSide.PressureDrop.fi = Kp1(13)/HotSide.HeatTransfer.Re^Kp2(13); |
---|
| 454 | ColdSide.PressureDrop.fi = Kp1(13)/ColdSide.HeatTransfer.Re^Kp2(13); |
---|
| 455 | else |
---|
| 456 | if HotSide.HeatTransfer.Re < 500 |
---|
| 457 | then |
---|
| 458 | HotSide.PressureDrop.fi = Kp1(14)/HotSide.HeatTransfer.Re^Kp2(14); |
---|
| 459 | ColdSide.PressureDrop.fi = Kp1(14)/ColdSide.HeatTransfer.Re^Kp2(14); |
---|
| 460 | else |
---|
| 461 | HotSide.PressureDrop.fi = Kp1(15)/HotSide.HeatTransfer.Re^Kp2(15); |
---|
| 462 | ColdSide.PressureDrop.fi = Kp1(15)/ColdSide.HeatTransfer.Re^Kp2(15); |
---|
| 463 | end |
---|
| 464 | |
---|
| 465 | end |
---|
| 466 | |
---|
| 467 | end |
---|
| 468 | |
---|
| 469 | switch ChevronAngle # Heat Transfer Coefficient According to kumar's (1984) |
---|
| 470 | |
---|
| 471 | case "A30_Deg": # ChevronAngle <= 30 |
---|
| 472 | |
---|
| 473 | if HotSide.HeatTransfer.Re < 10 |
---|
| 474 | then |
---|
| 475 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(1)*HotSide.HeatTransfer.Re^Kc2(1))/Dh; |
---|
| 476 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(1)*ColdSide.HeatTransfer.Re^Kc2(1))/Dh; |
---|
| 477 | else |
---|
| 478 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(2)*HotSide.HeatTransfer.Re^Kc2(2))/Dh; |
---|
| 479 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(2)*ColdSide.HeatTransfer.Re^Kc2(2))/Dh; |
---|
| 480 | end |
---|
| 481 | |
---|
| 482 | case "A45_Deg": |
---|
| 483 | |
---|
| 484 | if HotSide.HeatTransfer.Re < 10 |
---|
| 485 | then |
---|
| 486 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(3)*HotSide.HeatTransfer.Re^Kc2(3))/Dh; |
---|
| 487 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(3)*ColdSide.HeatTransfer.Re^Kc2(3))/Dh; |
---|
| 488 | else |
---|
| 489 | if HotSide.HeatTransfer.Re < 100 |
---|
| 490 | then |
---|
| 491 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(4)*HotSide.HeatTransfer.Re^Kc2(4))/Dh; |
---|
| 492 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(4)*ColdSide.HeatTransfer.Re^Kc2(4))/Dh; |
---|
| 493 | else |
---|
| 494 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(5)*HotSide.HeatTransfer.Re^Kc2(5))/Dh; |
---|
| 495 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(5)*ColdSide.HeatTransfer.Re^Kc2(5))/Dh; |
---|
| 496 | end |
---|
| 497 | end |
---|
| 498 | |
---|
| 499 | case "A50_Deg": |
---|
| 500 | |
---|
| 501 | if HotSide.HeatTransfer.Re < 20 |
---|
| 502 | then |
---|
| 503 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(6)*HotSide.HeatTransfer.Re^Kc2(6))/Dh; |
---|
| 504 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(6)*ColdSide.HeatTransfer.Re^Kc2(6))/Dh; |
---|
| 505 | else |
---|
| 506 | if HotSide.HeatTransfer.Re < 300 |
---|
| 507 | then |
---|
| 508 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(7)*HotSide.HeatTransfer.Re^Kc2(7))/Dh; |
---|
| 509 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(7)*ColdSide.HeatTransfer.Re^Kc2(7))/Dh; |
---|
| 510 | else |
---|
| 511 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(8)*HotSide.HeatTransfer.Re^Kc2(8))/Dh; |
---|
| 512 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(8)*ColdSide.HeatTransfer.Re^Kc2(8))/Dh; |
---|
| 513 | end |
---|
| 514 | end |
---|
| 515 | |
---|
| 516 | case "A60_Deg": |
---|
| 517 | |
---|
| 518 | if HotSide.HeatTransfer.Re < 20 |
---|
| 519 | then |
---|
| 520 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(9)*HotSide.HeatTransfer.Re^Kc2(9))/Dh; |
---|
| 521 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(9)*ColdSide.HeatTransfer.Re^Kc2(9))/Dh; |
---|
| 522 | else |
---|
| 523 | if HotSide.HeatTransfer.Re < 400 |
---|
| 524 | then |
---|
| 525 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(10)*HotSide.HeatTransfer.Re^Kc2(10))/Dh; |
---|
| 526 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(10)*ColdSide.HeatTransfer.Re^Kc2(10))/Dh; |
---|
| 527 | else |
---|
| 528 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(11)*HotSide.HeatTransfer.Re^Kc2(11))/Dh; |
---|
| 529 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(11)*ColdSide.HeatTransfer.Re^Kc2(11))/Dh; |
---|
| 530 | end |
---|
| 531 | end |
---|
| 532 | |
---|
| 533 | case "A65_Deg": # ChevronAngle >= 65 |
---|
| 534 | |
---|
| 535 | if HotSide.HeatTransfer.Re < 20 |
---|
| 536 | then |
---|
| 537 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(12)*HotSide.HeatTransfer.Re^Kc2(12))/Dh; |
---|
| 538 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(12)*ColdSide.HeatTransfer.Re^Kc2(12))/Dh; |
---|
| 539 | else |
---|
| 540 | if HotSide.HeatTransfer.Re < 500 |
---|
| 541 | then |
---|
| 542 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(13)*HotSide.HeatTransfer.Re^Kc2(13))/Dh; |
---|
| 543 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(13)*ColdSide.HeatTransfer.Re^Kc2(13))/Dh; |
---|
| 544 | else |
---|
| 545 | HotSide.HeatTransfer.hcoeff=(HotSide.Properties.Average.K*HotSide.HeatTransfer.PR^(1/3)*HotSide.HeatTransfer.Phi^0.17*Kc1(14)*HotSide.HeatTransfer.Re^Kc2(14))/Dh; |
---|
| 546 | ColdSide.HeatTransfer.hcoeff =(ColdSide.Properties.Average.K*ColdSide.HeatTransfer.PR^(1/3)*ColdSide.HeatTransfer.Phi^0.17*Kc1(14)*ColdSide.HeatTransfer.Re^Kc2(14))/Dh; |
---|
| 547 | end |
---|
| 548 | end |
---|
| 549 | |
---|
| 550 | end |
---|
| 551 | |
---|
| 552 | "Hot Stream Velocity in Channels" |
---|
| 553 | HotSide.PressureDrop.Vchannel =HotSide.HeatTransfer.Gchannel/HotSide.Properties.Average.rho; |
---|
| 554 | |
---|
| 555 | "Cold Stream Velocity in Channels" |
---|
| 556 | ColdSide.PressureDrop.Vchannel =ColdSide.HeatTransfer.Gchannel/ColdSide.Properties.Average.rho; |
---|
| 557 | |
---|
| 558 | "Hot Stream Velocity in Ports" |
---|
| 559 | HotSide.PressureDrop.Vports =HotSide.Properties.Inlet.Fw/(Aports*HotSide.Properties.Inlet.rho); |
---|
| 560 | |
---|
| 561 | "Cold Stream Velocity in Ports" |
---|
| 562 | ColdSide.PressureDrop.Vports =ColdSide.Properties.Inlet.Fw/(Aports*ColdSide.Properties.Inlet.rho); |
---|
| 563 | |
---|
| 564 | "Hot Stream Reynolds Number" |
---|
| 565 | HotSide.HeatTransfer.Re =Dh*HotSide.HeatTransfer.Gchannel/HotSide.Properties.Average.Mu; |
---|
| 566 | |
---|
| 567 | "Cold Stream Reynolds Number" |
---|
| 568 | ColdSide.HeatTransfer.Re =Dh*ColdSide.HeatTransfer.Gchannel/ColdSide.Properties.Average.Mu; |
---|
| 569 | |
---|
| 570 | "Hot Stream Prandtl Number" |
---|
| 571 | HotSide.HeatTransfer.PR= ((HotSide.Properties.Average.Cp/HotSide.Properties.Average.Mw)*HotSide.Properties.Average.Mu)/HotSide.Properties.Average.K; |
---|
| 572 | |
---|
| 573 | "Cold Stream Prandtl Number" |
---|
| 574 | ColdSide.HeatTransfer.PR = ((ColdSide.Properties.Average.Cp/ColdSide.Properties.Average.Mw)*ColdSide.Properties.Average.Mu)/ColdSide.Properties.Average.K; |
---|
| 575 | |
---|
| 576 | "Hot Stream Viscosity Correction" |
---|
| 577 | HotSide.HeatTransfer.Phi= HotSide.Properties.Average.Mu/HotSide.Properties.Wall.Mu; |
---|
| 578 | |
---|
| 579 | "Cold Stream Viscosity Correction" |
---|
| 580 | ColdSide.HeatTransfer.Phi= ColdSide.Properties.Average.Mu/ColdSide.Properties.Wall.Mu; |
---|
| 581 | |
---|
| 582 | "Hot Stream Outlet Pressure" |
---|
| 583 | OutletHot.P = InletHot.P - HotSide.PressureDrop.Pdrop; |
---|
| 584 | |
---|
| 585 | "Cold Stream Outlet Pressure" |
---|
| 586 | OutletCold.P = InletCold.P - ColdSide.PressureDrop.Pdrop; |
---|
| 587 | |
---|
| 588 | "Overall Heat Transfer Coefficient Clean" |
---|
| 589 | Thermal.Uc/HotSide.HeatTransfer.hcoeff +Thermal.Uc*pt/Kwall+Thermal.Uc/ColdSide.HeatTransfer.hcoeff=1; |
---|
| 590 | |
---|
| 591 | "Overall Heat Transfer Coefficient Dirty" |
---|
| 592 | Thermal.Ud*(1/HotSide.HeatTransfer.hcoeff +pt/Kwall+1/ColdSide.HeatTransfer.hcoeff + Rfc + Rfh)=1; |
---|
| 593 | |
---|
| 594 | "Duty" |
---|
| 595 | Thermal.Q = Thermal.Eft*Thermal.Cmin*(InletHot.T-InletCold.T); |
---|
| 596 | |
---|
| 597 | "Heat Capacity Ratio" |
---|
| 598 | Thermal.Cr =Thermal.Cmin/Thermal.Cmax; |
---|
| 599 | |
---|
| 600 | "Minimum Heat Capacity" |
---|
| 601 | Thermal.Cmin = min([HotSide.HeatTransfer.WCp,ColdSide.HeatTransfer.WCp]); |
---|
| 602 | |
---|
| 603 | "Maximum Heat Capacity" |
---|
| 604 | Thermal.Cmax = max([HotSide.HeatTransfer.WCp,ColdSide.HeatTransfer.WCp]); |
---|
| 605 | |
---|
| 606 | "Hot Stream Heat Capacity" |
---|
| 607 | HotSide.HeatTransfer.WCp = InletHot.F*HotSide.Properties.Average.Cp; |
---|
| 608 | |
---|
| 609 | "Cold Stream Heat Capacity" |
---|
| 610 | ColdSide.HeatTransfer.WCp = InletCold.F*ColdSide.Properties.Average.Cp; |
---|
| 611 | |
---|
| 612 | "Number of Units Transference for the Whole Heat Exchanger" |
---|
| 613 | Thermal.NTU = max([HotSide.HeatTransfer.NTU,ColdSide.HeatTransfer.NTU]); |
---|
| 614 | |
---|
| 615 | "Number of Units Transference for Hot Side" |
---|
| 616 | HotSide.HeatTransfer.NTU*HotSide.HeatTransfer.WCp = Thermal.Ud*Atotal; |
---|
| 617 | |
---|
| 618 | "Number of Units Transference for Cold Side" |
---|
| 619 | ColdSide.HeatTransfer.NTU*ColdSide.HeatTransfer.WCp = Thermal.Ud*Atotal; |
---|
| 620 | |
---|
| 621 | if Thermal.Eft >= 1 #To be Fixed: Effectiveness in true counter flow ! |
---|
| 622 | |
---|
| 623 | then |
---|
| 624 | "Effectiveness in Counter Flow" |
---|
| 625 | Thermal.Eft = 1; |
---|
| 626 | else |
---|
| 627 | "Effectiveness in Counter Flow" |
---|
| 628 | Thermal.NTU*(Thermal.Cr-1.00001) = ln(abs((Thermal.Eft-1.00001))) - ln(abs((Thermal.Cr*Thermal.Eft-1.00001))); |
---|
| 629 | |
---|
| 630 | end |
---|
| 631 | |
---|
| 632 | end |
---|