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 | " |
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28 | Model of a gasketed plate heat exchanger. |
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29 | The heat transfer and pressure loss calculations are based on Kumar [1] work. |
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30 | The following assumptions are considered in order to derive the mathematical model [2]: |
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31 | |
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32 | A.1 : Steady-State operation; |
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33 | A.2 : No phase changes; |
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34 | A.3 : No heat loss to the surroundings. |
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35 | A.4 : Uniform distribution of flow through the channels of a pass. |
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36 | |
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37 | References: |
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38 | |
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39 | [1] E.A.D. Saunders, Heat Exchangers: Selection, Design and |
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40 | Construction, Longman, Harlow, 1988. |
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41 | |
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42 | [2] J.A.W. Gut, J.M. Pinto, Modeling of plate heat exchangers |
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43 | with generalized configurations, Int. J. Heat Mass Transfer |
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44 | 46 (14) (2003) 2571\2585. |
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45 | "; |
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46 | |
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47 | PARAMETERS |
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48 | |
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49 | outer PP as Plugin (Brief="External Physical Properties", Type="PP"); |
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50 | outer NComp as Integer (Brief="Number of Chemical Components"); |
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51 | Pi as constant (Brief="Pi Number",Default=3.14159265); |
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52 | Kp1(15) as constant (Brief="First constant in Kumar calculation for Pressure Drop"); |
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53 | Kp2(15) as constant (Brief="Second constant in Kumar calculation for Pressure Drop"); |
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54 | Kc1(14) as constant (Brief="First constant in Kumar calculation for Heat Transfer"); |
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55 | Kc2(14) as constant (Brief="Second constant Kumar calculation for Heat Transfer"); |
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56 | M(NComp) as molweight (Brief="Component Mol Weight"); |
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57 | |
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58 | ChevronAngle as Switcher (Brief="Chevron Corrugation Inclination Angle in Degrees ",Valid=["30","45","50","60","65"],Default="30"); |
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59 | Method as Switcher (Brief="Method of Thermal Calculation",Valid=["NTU","LMTD"],Default="NTU"); |
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60 | SideOne as Switcher (Brief="Fluid Alocation in the Side I - (The odd channels)",Valid=["hot","cold"],Default="hot"); |
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61 | Nchannels as Integer (Brief="Total Number of Channels in The Whole Heat Exchanger"); |
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62 | Nplates as Integer (Brief="Total Number of Plates in The Whole Heat Exchanger",Default=25); |
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63 | NpassHot as Integer (Brief="Number of Passes for Hot Side"); |
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64 | NpassCold as Integer (Brief="Number of Passes for Cold Side"); |
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65 | Dports as length (Brief="Ports Diameter",Lower=1e-6); |
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66 | Atotal as area (Brief="Total Effective Area",Lower=1e-6); |
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67 | Aports as area (Brief="Port Opening Area of Plate",Lower=1e-6); |
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68 | Achannel as area (Brief="Cross-Sectional Area for Channel Flow",Lower=1e-6); |
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69 | Dh as length (Brief="Equivalent Diameter of Channel",Lower=1e-6); |
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70 | Depth as length (Brief="Corrugation Depth",Lower=1e-6); |
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71 | PhiFactor as Real (Brief="Enlargement Factor",Lower=1e-6); |
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72 | Lp as length (Brief="Plate Vertical Distance between Port Centers",Lower=0.1); |
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73 | Lpack as length (Brief="Compact Plate Pack Length",Lower=0.1); |
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74 | Lv as length (Brief="Vertical Ports Distance",Lower=0.1); |
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75 | Lh as length (Brief="Plate Horizontal Distance between Port Centers",Lower=0.1); |
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76 | Lw as length (Brief="Plate Width",Lower=0.1); |
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77 | pitch as length (Brief="Plate Pitch",Lower=0.1); |
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78 | pt as length (Brief="Plate Thickness",Lower=0.1); |
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79 | Kwall as conductivity (Brief="Plate Thermal Conductivity",Default=1.0); |
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80 | Rfh as positive (Brief="Hot Side Fouling Resistance",Unit='m^2*K/kW',Default=1e-6,Lower=0); |
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81 | Rfc as positive (Brief="Cold Side Fouling Resistance",Unit='m^2*K/kW',Default=1e-6,Lower=0); |
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82 | |
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83 | VARIABLES |
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84 | |
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85 | in InletHot as stream (Brief="Inlet Hot Stream", PosX=0, PosY=0.7156); |
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86 | in InletCold as stream (Brief="Inlet Cold Stream", PosX=1, PosY=0.7156); |
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87 | out OutletHot as streamPH (Brief="Outlet Hot Stream", PosX=0, PosY=0.2793); |
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88 | out OutletCold as streamPH (Brief="Outlet Cold Stream", PosX=1, PosY=0.2793); |
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89 | |
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90 | HotSide as Main_PHE (Brief="Plate Heat Exchanger Hot Side"); |
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91 | ColdSide as Main_PHE (Brief="Plate Heat Exchanger Cold Side"); |
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92 | Thermal as Thermal_PHE (Brief="Thermal Results"); |
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93 | |
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94 | SET |
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95 | |
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96 | #"First constant for Kumar's calculating Pressure Drop" |
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97 | 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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98 | |
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99 | #"Second constant for Kumar's calculating Pressure Drop" |
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100 | 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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101 | |
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102 | #"First constant for Kumar's calculating Heat Transfer" |
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103 | 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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104 | |
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105 | #"Second constant for Kumar's calculating Heat Transfer" |
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106 | 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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107 | |
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108 | #"Component Molecular Weight" |
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109 | M = PP.MolecularWeight(); |
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110 | |
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111 | #"Pi Number" |
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112 | Pi = 3.14159265; |
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113 | |
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114 | #"Plate Vertical Distance between Port Centers" |
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115 | Lp = Lv - Dports; |
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116 | |
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117 | #"Corrugation Depth" |
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118 | Depth=pitch-pt; |
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119 | |
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120 | #"Plate Horizontal Distance between Port Centers" |
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121 | Lh=Lw-Dports; |
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122 | |
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123 | #"Hydraulic Diameter" |
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124 | Dh=2*Depth/PhiFactor; |
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125 | |
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126 | #"Ports Area" |
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127 | Aports=Pi*Dports*Dports/4; |
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128 | |
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129 | #"Channel Area" |
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130 | Achannel=Depth*Lw; |
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131 | |
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132 | #"Pack Length" |
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133 | Lpack=Depth*(Nplates-1)+Nplates*pt; |
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134 | |
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135 | #"Total Number of Channels" |
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136 | Nchannels = Nplates -1; |
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137 | |
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138 | #"Exchange Surface Area" |
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139 | Atotal =(Nplates-2)*Lw*Lp*PhiFactor; |
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140 | |
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141 | EQUATIONS |
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142 | |
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143 | "Hot Stream Average Temperature" |
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144 | HotSide.Properties.Average.T = 0.5*InletHot.T + 0.5*OutletHot.T; |
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145 | |
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146 | "Cold Stream Average Temperature" |
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147 | ColdSide.Properties.Average.T = 0.5*InletCold.T + 0.5*OutletCold.T; |
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148 | |
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149 | "Hot Stream Average Pressure" |
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150 | HotSide.Properties.Average.P = 0.5*InletHot.P+0.5*OutletHot.P; |
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151 | |
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152 | "Cold Stream Average Pressure" |
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153 | ColdSide.Properties.Average.P = 0.5*InletCold.P+0.5*OutletCold.P; |
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154 | |
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155 | "Cold Stream Wall Temperature" |
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156 | ColdSide.Properties.Wall.Twall = 0.5*HotSide.Properties.Average.T + 0.5*ColdSide.Properties.Average.T; |
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157 | |
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158 | "Hot Stream Wall Temperature" |
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159 | HotSide.Properties.Wall.Twall = 0.5*HotSide.Properties.Average.T + 0.5*ColdSide.Properties.Average.T; |
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160 | |
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161 | "Hot Stream Average Molecular Weight" |
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162 | HotSide.Properties.Average.Mw = sum(M*InletHot.z); |
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163 | |
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164 | "Cold Stream Average Molecular Weight" |
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165 | ColdSide.Properties.Average.Mw = sum(M*InletCold.z); |
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166 | |
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167 | if InletCold.v equal 0 |
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168 | |
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169 | then |
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170 | |
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171 | "Average Heat Capacity Cold Stream" |
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172 | ColdSide.Properties.Average.Cp = PP.LiquidCp(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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173 | |
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174 | "Inlet Heat Capacity Cold Stream" |
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175 | ColdSide.Properties.Inlet.Cp = PP.LiquidCp(InletCold.T,InletCold.P,InletCold.z); |
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176 | |
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177 | "Outlet Heat Capacity Cold Stream" |
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178 | ColdSide.Properties.Outlet.Cp = PP.LiquidCp(OutletCold.T,OutletCold.P,OutletCold.z); |
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179 | |
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180 | "Average Mass Density Cold Stream" |
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181 | ColdSide.Properties.Average.rho = PP.LiquidDensity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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182 | |
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183 | "Inlet Mass Density Cold Stream" |
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184 | ColdSide.Properties.Inlet.rho = PP.LiquidDensity(InletCold.T,InletCold.P,InletCold.z); |
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185 | |
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186 | "Outlet Mass Density Cold Stream" |
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187 | ColdSide.Properties.Outlet.rho = PP.LiquidDensity(OutletCold.T,OutletCold.P,OutletCold.z); |
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188 | |
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189 | "Average Viscosity Cold Stream" |
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190 | ColdSide.Properties.Average.Mu = PP.LiquidViscosity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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191 | |
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192 | "Inlet Viscosity Cold Stream" |
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193 | ColdSide.Properties.Inlet.Mu = PP.LiquidViscosity(InletCold.T,InletCold.P,InletCold.z); |
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194 | |
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195 | "Outlet Viscosity Cold Stream" |
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196 | ColdSide.Properties.Outlet.Mu = PP.LiquidViscosity(OutletCold.T,OutletCold.P,OutletCold.z); |
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197 | |
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198 | "Average Conductivity Cold Stream" |
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199 | ColdSide.Properties.Average.K = PP.LiquidThermalConductivity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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200 | |
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201 | "Inlet Conductivity Cold Stream" |
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202 | ColdSide.Properties.Inlet.K = PP.LiquidThermalConductivity(InletCold.T,InletCold.P,InletCold.z); |
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203 | |
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204 | "Outlet Conductivity Cold Stream" |
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205 | ColdSide.Properties.Outlet.K = PP.LiquidThermalConductivity(OutletCold.T,OutletCold.P,OutletCold.z); |
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206 | |
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207 | "Viscosity Cold Stream at wall temperature" |
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208 | ColdSide.Properties.Wall.Mu = PP.LiquidViscosity(ColdSide.Properties.Wall.Twall,ColdSide.Properties.Average.P,InletCold.z); |
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209 | |
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210 | else |
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211 | |
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212 | "Average Heat Capacity ColdStream" |
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213 | ColdSide.Properties.Average.Cp = PP.VapourCp(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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214 | |
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215 | "Inlet Heat Capacity Cold Stream" |
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216 | ColdSide.Properties.Inlet.Cp = PP.VapourCp(InletCold.T,InletCold.P,InletCold.z); |
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217 | |
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218 | "Outlet Heat Capacity Cold Stream" |
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219 | ColdSide.Properties.Outlet.Cp = PP.VapourCp(OutletCold.T,OutletCold.P,OutletCold.z); |
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220 | |
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221 | "Average Mass Density Cold Stream" |
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222 | ColdSide.Properties.Average.rho = PP.VapourDensity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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223 | |
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224 | "Inlet Mass Density Cold Stream" |
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225 | ColdSide.Properties.Inlet.rho = PP.VapourDensity(InletCold.T,InletCold.P,InletCold.z); |
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226 | |
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227 | "Outlet Mass Density Cold Stream" |
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228 | ColdSide.Properties.Outlet.rho = PP.VapourDensity(OutletCold.T,OutletCold.P,OutletCold.z); |
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229 | |
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230 | "Average Viscosity Cold Stream" |
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231 | ColdSide.Properties.Average.Mu = PP.VapourViscosity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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232 | |
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233 | "Inlet Viscosity Cold Stream" |
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234 | ColdSide.Properties.Inlet.Mu = PP.VapourViscosity(InletCold.T,InletCold.P,InletCold.z); |
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235 | |
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236 | "Outlet Viscosity Cold Stream" |
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237 | ColdSide.Properties.Outlet.Mu = PP.VapourViscosity(OutletCold.T,OutletCold.P,OutletCold.z); |
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238 | |
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239 | "Average Conductivity Cold Stream" |
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240 | ColdSide.Properties.Average.K = PP.VapourThermalConductivity(ColdSide.Properties.Average.T,ColdSide.Properties.Average.P,InletCold.z); |
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241 | |
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242 | "Inlet Conductivity Cold Stream" |
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243 | ColdSide.Properties.Inlet.K = PP.VapourThermalConductivity(InletCold.T,InletCold.P,InletCold.z); |
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244 | |
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245 | "Outlet Conductivity Cold Stream" |
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246 | ColdSide.Properties.Outlet.K = PP.VapourThermalConductivity(OutletCold.T,OutletCold.P,OutletCold.z); |
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247 | |
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248 | "Viscosity Cold Stream at wall temperature" |
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249 | ColdSide.Properties.Wall.Mu = PP.VapourViscosity(ColdSide.Properties.Wall.Twall,ColdSide.Properties.Average.P,InletCold.z); |
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250 | |
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251 | end |
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252 | |
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253 | if InletHot.v equal 0 |
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254 | |
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255 | then |
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256 | |
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257 | "Average Heat Capacity Hot Stream" |
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258 | HotSide.Properties.Average.Cp = PP.LiquidCp(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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259 | |
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260 | "Inlet Heat Capacity Hot Stream" |
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261 | HotSide.Properties.Inlet.Cp = PP.LiquidCp(InletHot.T,InletHot.P,InletHot.z); |
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262 | |
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263 | "Outlet Heat Capacity Hot Stream" |
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264 | HotSide.Properties.Outlet.Cp = PP.LiquidCp(OutletHot.T,OutletHot.P,OutletHot.z); |
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265 | |
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266 | "Average Mass Density Hot Stream" |
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267 | HotSide.Properties.Average.rho = PP.LiquidDensity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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268 | |
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269 | "Inlet Mass Density Hot Stream" |
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270 | HotSide.Properties.Inlet.rho = PP.LiquidDensity(InletHot.T,InletHot.P,InletHot.z); |
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271 | |
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272 | "Outlet Mass Density Hot Stream" |
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273 | HotSide.Properties.Outlet.rho = PP.LiquidDensity(OutletHot.T,OutletHot.P,OutletHot.z); |
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274 | |
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275 | "Average Viscosity Hot Stream" |
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276 | HotSide.Properties.Average.Mu = PP.LiquidViscosity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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277 | |
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278 | "Inlet Viscosity Hot Stream" |
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279 | HotSide.Properties.Inlet.Mu = PP.LiquidViscosity(InletHot.T,InletHot.P,InletHot.z); |
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280 | |
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281 | "Outlet Viscosity Hot Stream" |
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282 | HotSide.Properties.Outlet.Mu = PP.LiquidViscosity(OutletHot.T,OutletHot.P,OutletHot.z); |
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283 | |
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284 | "Average Conductivity Hot Stream" |
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285 | HotSide.Properties.Average.K = PP.LiquidThermalConductivity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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286 | |
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287 | "Inlet Conductivity Hot Stream" |
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288 | HotSide.Properties.Inlet.K = PP.LiquidThermalConductivity(InletHot.T,InletHot.P,InletHot.z); |
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289 | |
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290 | "Outlet Conductivity Hot Stream" |
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291 | HotSide.Properties.Outlet.K = PP.LiquidThermalConductivity(OutletHot.T,OutletHot.P,OutletHot.z); |
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292 | |
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293 | "Viscosity Hot Stream at wall temperature" |
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294 | HotSide.Properties.Wall.Mu = PP.LiquidViscosity(HotSide.Properties.Wall.Twall,HotSide.Properties.Average.P,InletHot.z); |
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295 | |
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296 | |
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297 | else |
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298 | |
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299 | "Average Heat Capacity Hot Stream" |
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300 | HotSide.Properties.Average.Cp = PP.VapourCp(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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301 | |
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302 | "Inlet Heat Capacity Hot Stream" |
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303 | HotSide.Properties.Inlet.Cp = PP.VapourCp(InletHot.T,InletHot.P,InletHot.z); |
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304 | |
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305 | "Outlet Heat Capacity Hot Stream" |
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306 | HotSide.Properties.Outlet.Cp = PP.VapourCp(OutletHot.T,OutletHot.P,OutletHot.z); |
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307 | |
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308 | "Average Mass Density Hot Stream" |
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309 | HotSide.Properties.Average.rho = PP.VapourDensity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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310 | |
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311 | "Inlet Mass Density Hot Stream" |
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312 | HotSide.Properties.Inlet.rho = PP.VapourDensity(InletHot.T,InletHot.P,InletHot.z); |
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313 | |
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314 | "Outlet Mass Density Hot Stream" |
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315 | HotSide.Properties.Outlet.rho = PP.VapourDensity(OutletHot.T,OutletHot.P,OutletHot.z); |
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316 | |
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317 | "Average Viscosity Hot Stream" |
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318 | HotSide.Properties.Average.Mu = PP.VapourViscosity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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319 | |
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320 | "Inlet Viscosity Hot Stream" |
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321 | HotSide.Properties.Inlet.Mu = PP.VapourViscosity(InletHot.T,InletHot.P,InletHot.z); |
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322 | |
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323 | "Outlet Viscosity Hot Stream" |
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324 | HotSide.Properties.Outlet.Mu = PP.VapourViscosity(OutletHot.T,OutletHot.P,OutletHot.z); |
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325 | |
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326 | "Average Conductivity Hot Stream" |
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327 | HotSide.Properties.Average.K = PP.VapourThermalConductivity(HotSide.Properties.Average.T,HotSide.Properties.Average.P,InletHot.z); |
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328 | |
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329 | "Inlet Conductivity Hot Stream" |
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330 | HotSide.Properties.Inlet.K = PP.VapourThermalConductivity(InletHot.T,InletHot.P,InletHot.z); |
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331 | |
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332 | "Outlet Conductivity Hot Stream" |
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333 | HotSide.Properties.Outlet.K = PP.VapourThermalConductivity(OutletHot.T,OutletHot.P,OutletHot.z); |
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334 | |
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335 | "Viscosity Hot Stream at wall temperature" |
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336 | HotSide.Properties.Wall.Mu = PP.VapourViscosity(HotSide.Properties.Wall.Twall,HotSide.Properties.Average.P,InletHot.z); |
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337 | |
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338 | end |
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339 | |
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340 | "Energy Balance Hot Stream" |
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341 | Thermal.Q = InletHot.F*(InletHot.h-OutletHot.h); |
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342 | |
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343 | "Energy Balance Cold Stream" |
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344 | Thermal.Q = InletCold.F*(OutletCold.h - InletCold.h); |
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345 | |
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346 | "Flow Mass Inlet Cold Stream" |
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347 | ColdSide.Properties.Inlet.Fw = sum(M*InletCold.z)*InletCold.F; |
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348 | |
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349 | "Flow Mass Outlet Cold Stream" |
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350 | ColdSide.Properties.Outlet.Fw = sum(M*OutletCold.z)*OutletCold.F; |
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351 | |
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352 | "Flow Mass Inlet Hot Stream" |
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353 | HotSide.Properties.Inlet.Fw = sum(M*InletHot.z)*InletHot.F; |
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354 | |
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355 | "Flow Mass Outlet Hot Stream" |
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356 | HotSide.Properties.Outlet.Fw = sum(M*OutletHot.z)*OutletHot.F; |
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357 | |
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358 | "Molar Balance Hot Stream" |
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359 | OutletHot.F = InletHot.F; |
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360 | |
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361 | "Molar Balance Cold Stream" |
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362 | OutletCold.F = InletCold.F; |
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363 | |
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364 | "Hot Stream Molar Fraction Constraint" |
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365 | OutletHot.z=InletHot.z; |
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366 | |
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367 | "Cold Stream Molar Fraction Constraint" |
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368 | OutletCold.z=InletCold.z; |
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369 | |
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370 | switch SideOne |
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371 | |
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372 | case "cold": |
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373 | |
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374 | "Total Number of Passages Cold Side" |
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375 | ColdSide.PressureDrop.Npassage = (2*Nchannels+1+(-1)^(Nchannels+1))/(4*NpassCold); |
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376 | |
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377 | "Total Number of Passages Hot Side" |
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378 | HotSide.PressureDrop.Npassage = (2*Nchannels-1+(-1)^(Nchannels))/(4*NpassHot); |
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379 | |
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380 | case "hot": |
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381 | |
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382 | "Total Number of Passages Cold Side" |
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383 | HotSide.PressureDrop.Npassage = (2*Nchannels+1+(-1)^(Nchannels+1))/(4*NpassHot); |
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384 | |
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385 | "Total Number of Passages Hot Side" |
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386 | ColdSide.PressureDrop.Npassage = (2*Nchannels-1+(-1)^(Nchannels))/(4*NpassCold); |
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387 | |
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388 | end |
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389 | |
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390 | "Hot Stream Mass Flux in the Channel" |
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391 | HotSide.HeatTransfer.Gchannel=HotSide.Properties.Inlet.Fw/(HotSide.PressureDrop.Npassage*Achannel); |
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392 | |
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393 | "Hot Stream Mass Flux in the Ports" |
---|
394 | HotSide.HeatTransfer.Gports=HotSide.Properties.Inlet.Fw/Aports; |
---|
395 | |
---|
396 | "Cold Stream Mass Flux in the Ports" |
---|
397 | ColdSide.HeatTransfer.Gports=ColdSide.Properties.Inlet.Fw/Aports; |
---|
398 | |
---|
399 | "Cold Stream Mass Flux in the Channel" |
---|
400 | ColdSide.HeatTransfer.Gchannel=ColdSide.Properties.Inlet.Fw/(ColdSide.PressureDrop.Npassage*Achannel); |
---|
401 | |
---|
402 | "Hot Stream Pressure Drop in Ports" |
---|
403 | HotSide.PressureDrop.DPports =1.5*NpassHot*HotSide.HeatTransfer.Gports^2/(2*HotSide.Properties.Average.rho); |
---|
404 | |
---|
405 | "Cold Stream Pressure Drop in Ports" |
---|
406 | ColdSide.PressureDrop.DPports =1.5*NpassCold*ColdSide.HeatTransfer.Gports^2/(2*ColdSide.Properties.Average.rho); |
---|
407 | |
---|
408 | "Hot Stream Pressure Drop in Channels" |
---|
409 | HotSide.PressureDrop.DPchannel =2*HotSide.PressureDrop.fi*NpassHot*Lv*HotSide.HeatTransfer.Gchannel^2/(HotSide.Properties.Average.rho*Dh*HotSide.HeatTransfer.Phi^0.17); |
---|
410 | |
---|
411 | "Cold Stream Pressure Drop in Channels" |
---|
412 | ColdSide.PressureDrop.DPchannel =2*ColdSide.PressureDrop.fi*NpassCold*Lv*ColdSide.HeatTransfer.Gchannel^2/(ColdSide.Properties.Average.rho*Dh*ColdSide.HeatTransfer.Phi^0.17); |
---|
413 | |
---|
414 | "Hot Stream Total Pressure Drop" |
---|
415 | HotSide.PressureDrop.Pdrop =HotSide.PressureDrop.DPchannel+HotSide.PressureDrop.DPports; |
---|
416 | |
---|
417 | "Cold Stream Total Pressure Drop" |
---|
418 | ColdSide.PressureDrop.Pdrop =ColdSide.PressureDrop.DPchannel+ColdSide.PressureDrop.DPports; |
---|
419 | |
---|
420 | switch ChevronAngle #Pressure Drop Friction Factor According to kumar's (1984) |
---|
421 | |
---|
422 | case "30": # ChevronAngle <= 30 |
---|
423 | |
---|
424 | if HotSide.HeatTransfer.Re < 10 |
---|
425 | then |
---|
426 | HotSide.PressureDrop.fi = Kp1(1)/HotSide.HeatTransfer.Re^Kp2(1); |
---|
427 | ColdSide.PressureDrop.fi = Kp1(1)/ColdSide.HeatTransfer.Re^Kp2(1); |
---|
428 | else |
---|
429 | if HotSide.HeatTransfer.Re < 100 |
---|
430 | then |
---|
431 | HotSide.PressureDrop.fi = Kp1(2)/HotSide.HeatTransfer.Re^Kp2(2); |
---|
432 | ColdSide.PressureDrop.fi = Kp1(2)/ColdSide.HeatTransfer.Re^Kp2(2); |
---|
433 | else |
---|
434 | HotSide.PressureDrop.fi = Kp1(3)/HotSide.HeatTransfer.Re^Kp2(3); |
---|
435 | ColdSide.PressureDrop.fi = Kp1(3)/ColdSide.HeatTransfer.Re^Kp2(3); |
---|
436 | end |
---|
437 | |
---|
438 | end |
---|
439 | |
---|
440 | case "45": |
---|
441 | |
---|
442 | if HotSide.HeatTransfer.Re < 15 |
---|
443 | then |
---|
444 | HotSide.PressureDrop.fi = Kp1(4)/HotSide.HeatTransfer.Re^Kp2(4); |
---|
445 | ColdSide.PressureDrop.fi = Kp1(4)/ColdSide.HeatTransfer.Re^Kp2(4); |
---|
446 | else |
---|
447 | if HotSide.HeatTransfer.Re < 300 |
---|
448 | then |
---|
449 | HotSide.PressureDrop.fi = Kp1(5)/HotSide.HeatTransfer.Re^Kp2(5); |
---|
450 | ColdSide.PressureDrop.fi = Kp1(5)/ColdSide.HeatTransfer.Re^Kp2(5); |
---|
451 | else |
---|
452 | HotSide.PressureDrop.fi = Kp1(6)/HotSide.HeatTransfer.Re^Kp2(6); |
---|
453 | ColdSide.PressureDrop.fi = Kp1(6)/ColdSide.HeatTransfer.Re^Kp2(6); |
---|
454 | end |
---|
455 | |
---|
456 | end |
---|
457 | |
---|
458 | case "50": |
---|
459 | |
---|
460 | if HotSide.HeatTransfer.Re < 20 |
---|
461 | then |
---|
462 | HotSide.PressureDrop.fi = Kp1(7)/HotSide.HeatTransfer.Re^Kp2(7); |
---|
463 | ColdSide.PressureDrop.fi = Kp1(7)/ColdSide.HeatTransfer.Re^Kp2(7); |
---|
464 | else |
---|
465 | if HotSide.HeatTransfer.Re < 300 |
---|
466 | then |
---|
467 | HotSide.PressureDrop.fi = Kp1(8)/HotSide.HeatTransfer.Re^Kp2(8); |
---|
468 | ColdSide.PressureDrop.fi = Kp1(8)/ColdSide.HeatTransfer.Re^Kp2(8); |
---|
469 | else |
---|
470 | HotSide.PressureDrop.fi = Kp1(9)/HotSide.HeatTransfer.Re^Kp2(9); |
---|
471 | ColdSide.PressureDrop.fi = Kp1(9)/ColdSide.HeatTransfer.Re^Kp2(9); |
---|
472 | end |
---|
473 | |
---|
474 | end |
---|
475 | |
---|
476 | case "60": |
---|
477 | |
---|
478 | if HotSide.HeatTransfer.Re < 40 |
---|
479 | then |
---|
480 | HotSide.PressureDrop.fi = Kp1(10)/HotSide.HeatTransfer.Re^Kp2(10); |
---|
481 | ColdSide.PressureDrop.fi = Kp1(10)/ColdSide.HeatTransfer.Re^Kp2(10); |
---|
482 | else |
---|
483 | if HotSide.HeatTransfer.Re < 400 |
---|
484 | then |
---|
485 | HotSide.PressureDrop.fi = Kp1(11)/HotSide.HeatTransfer.Re^Kp2(11); |
---|
486 | ColdSide.PressureDrop.fi = Kp1(11)/ColdSide.HeatTransfer.Re^Kp2(11); |
---|
487 | else |
---|
488 | HotSide.PressureDrop.fi = Kp1(12)/HotSide.HeatTransfer.Re^Kp2(12); |
---|
489 | ColdSide.PressureDrop.fi = Kp1(12)/ColdSide.HeatTransfer.Re^Kp2(12); |
---|
490 | end |
---|
491 | |
---|
492 | end |
---|
493 | |
---|
494 | case "65": # ChevronAngle >= 65 |
---|
495 | |
---|
496 | if HotSide.HeatTransfer.Re < 50 |
---|
497 | then |
---|
498 | HotSide.PressureDrop.fi = Kp1(13)/HotSide.HeatTransfer.Re^Kp2(13); |
---|
499 | ColdSide.PressureDrop.fi = Kp1(13)/ColdSide.HeatTransfer.Re^Kp2(13); |
---|
500 | else |
---|
501 | if HotSide.HeatTransfer.Re < 500 |
---|
502 | then |
---|
503 | HotSide.PressureDrop.fi = Kp1(14)/HotSide.HeatTransfer.Re^Kp2(14); |
---|
504 | ColdSide.PressureDrop.fi = Kp1(14)/ColdSide.HeatTransfer.Re^Kp2(14); |
---|
505 | else |
---|
506 | HotSide.PressureDrop.fi = Kp1(15)/HotSide.HeatTransfer.Re^Kp2(15); |
---|
507 | ColdSide.PressureDrop.fi = Kp1(15)/ColdSide.HeatTransfer.Re^Kp2(15); |
---|
508 | end |
---|
509 | |
---|
510 | end |
---|
511 | |
---|
512 | end |
---|
513 | |
---|
514 | switch ChevronAngle # Heat Transfer Coefficient According to kumar's (1984) |
---|
515 | |
---|
516 | case "30": # ChevronAngle <= 30 |
---|
517 | |
---|
518 | if HotSide.HeatTransfer.Re < 10 |
---|
519 | then |
---|
520 | 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; |
---|
521 | 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; |
---|
522 | else |
---|
523 | 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; |
---|
524 | 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; |
---|
525 | end |
---|
526 | |
---|
527 | case "45": |
---|
528 | |
---|
529 | if HotSide.HeatTransfer.Re < 10 |
---|
530 | then |
---|
531 | 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; |
---|
532 | 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; |
---|
533 | else |
---|
534 | if HotSide.HeatTransfer.Re < 100 |
---|
535 | then |
---|
536 | 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; |
---|
537 | 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; |
---|
538 | else |
---|
539 | 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; |
---|
540 | 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; |
---|
541 | end |
---|
542 | end |
---|
543 | |
---|
544 | case "50": |
---|
545 | |
---|
546 | if HotSide.HeatTransfer.Re < 20 |
---|
547 | then |
---|
548 | 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; |
---|
549 | 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; |
---|
550 | else |
---|
551 | if HotSide.HeatTransfer.Re < 300 |
---|
552 | then |
---|
553 | 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; |
---|
554 | 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; |
---|
555 | else |
---|
556 | 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; |
---|
557 | 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; |
---|
558 | end |
---|
559 | end |
---|
560 | |
---|
561 | case "60": |
---|
562 | |
---|
563 | if HotSide.HeatTransfer.Re < 20 |
---|
564 | then |
---|
565 | 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; |
---|
566 | 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; |
---|
567 | else |
---|
568 | if HotSide.HeatTransfer.Re < 400 |
---|
569 | then |
---|
570 | 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; |
---|
571 | 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; |
---|
572 | else |
---|
573 | 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; |
---|
574 | 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; |
---|
575 | end |
---|
576 | end |
---|
577 | |
---|
578 | case "65": # ChevronAngle >= 65 |
---|
579 | |
---|
580 | if HotSide.HeatTransfer.Re < 20 |
---|
581 | then |
---|
582 | 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; |
---|
583 | 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; |
---|
584 | else |
---|
585 | if HotSide.HeatTransfer.Re < 500 |
---|
586 | then |
---|
587 | 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; |
---|
588 | 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; |
---|
589 | else |
---|
590 | 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; |
---|
591 | 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; |
---|
592 | end |
---|
593 | end |
---|
594 | |
---|
595 | end |
---|
596 | |
---|
597 | "Hot Stream Velocity in Channels" |
---|
598 | HotSide.PressureDrop.Vchannel =HotSide.HeatTransfer.Gchannel/HotSide.Properties.Average.rho; |
---|
599 | |
---|
600 | "Cold Stream Velocity in Channels" |
---|
601 | ColdSide.PressureDrop.Vchannel =ColdSide.HeatTransfer.Gchannel/ColdSide.Properties.Average.rho; |
---|
602 | |
---|
603 | "Hot Stream Velocity in Ports" |
---|
604 | HotSide.PressureDrop.Vports =HotSide.Properties.Inlet.Fw/(Aports*HotSide.Properties.Inlet.rho); |
---|
605 | |
---|
606 | "Cold Stream Velocity in Ports" |
---|
607 | ColdSide.PressureDrop.Vports =ColdSide.Properties.Inlet.Fw/(Aports*ColdSide.Properties.Inlet.rho); |
---|
608 | |
---|
609 | "Hot Stream Reynolds Number" |
---|
610 | HotSide.HeatTransfer.Re =Dh*HotSide.HeatTransfer.Gchannel/HotSide.Properties.Average.Mu; |
---|
611 | |
---|
612 | "Cold Stream Reynolds Number" |
---|
613 | ColdSide.HeatTransfer.Re =Dh*ColdSide.HeatTransfer.Gchannel/ColdSide.Properties.Average.Mu; |
---|
614 | |
---|
615 | "Hot Stream Prandtl Number" |
---|
616 | HotSide.HeatTransfer.PR= ((HotSide.Properties.Average.Cp/HotSide.Properties.Average.Mw)*HotSide.Properties.Average.Mu)/HotSide.Properties.Average.K; |
---|
617 | |
---|
618 | "Cold Stream Prandtl Number" |
---|
619 | ColdSide.HeatTransfer.PR = ((ColdSide.Properties.Average.Cp/ColdSide.Properties.Average.Mw)*ColdSide.Properties.Average.Mu)/ColdSide.Properties.Average.K; |
---|
620 | |
---|
621 | "Hot Stream Viscosity Correction" |
---|
622 | HotSide.HeatTransfer.Phi= HotSide.Properties.Average.Mu/HotSide.Properties.Wall.Mu; |
---|
623 | |
---|
624 | "Cold Stream Viscosity Correction" |
---|
625 | ColdSide.HeatTransfer.Phi= ColdSide.Properties.Average.Mu/ColdSide.Properties.Wall.Mu; |
---|
626 | |
---|
627 | "Hot Stream Outlet Pressure" |
---|
628 | OutletHot.P = InletHot.P - HotSide.PressureDrop.Pdrop; |
---|
629 | |
---|
630 | "Cold Stream Outlet Pressure" |
---|
631 | OutletCold.P = InletCold.P - ColdSide.PressureDrop.Pdrop; |
---|
632 | |
---|
633 | "Overall Heat Transfer Coefficient Clean" |
---|
634 | Thermal.Uc/HotSide.HeatTransfer.hcoeff +Thermal.Uc*pt/Kwall+Thermal.Uc/ColdSide.HeatTransfer.hcoeff=1; |
---|
635 | |
---|
636 | "Overall Heat Transfer Coefficient Dirty" |
---|
637 | Thermal.Ud*(1/HotSide.HeatTransfer.hcoeff +pt/Kwall+1/ColdSide.HeatTransfer.hcoeff + Rfc + Rfh)=1; |
---|
638 | |
---|
639 | switch Method |
---|
640 | |
---|
641 | case "LMTD": |
---|
642 | |
---|
643 | "Duty" |
---|
644 | Thermal.Q = Thermal.Ud*Atotal*Thermal.LMTD*Thermal.Fc; |
---|
645 | |
---|
646 | case "NTU": |
---|
647 | |
---|
648 | "Duty" |
---|
649 | Thermal.Q = Thermal.Eft*Thermal.Cmin*(InletHot.T-InletCold.T); |
---|
650 | |
---|
651 | end |
---|
652 | |
---|
653 | "Temperature Difference at Inlet - Counter Flow" |
---|
654 | Thermal.DT0 = InletHot.T - OutletCold.T; |
---|
655 | |
---|
656 | "Temperature Difference at Outlet - Counter Flow" |
---|
657 | Thermal.DTL = OutletHot.T - InletCold.T; |
---|
658 | |
---|
659 | "Heat Capacity Ratio" |
---|
660 | Thermal.Cr =Thermal.Cmin/Thermal.Cmax; |
---|
661 | |
---|
662 | "Minimum Heat Capacity" |
---|
663 | Thermal.Cmin = min([HotSide.HeatTransfer.WCp,ColdSide.HeatTransfer.WCp]); |
---|
664 | |
---|
665 | "Maximum Heat Capacity" |
---|
666 | Thermal.Cmax = max([HotSide.HeatTransfer.WCp,ColdSide.HeatTransfer.WCp]); |
---|
667 | |
---|
668 | "Hot Stream Heat Capacity" |
---|
669 | HotSide.HeatTransfer.WCp = InletHot.F*HotSide.Properties.Average.Cp; |
---|
670 | |
---|
671 | "Cold Stream Heat Capacity" |
---|
672 | ColdSide.HeatTransfer.WCp = InletCold.F*ColdSide.Properties.Average.Cp; |
---|
673 | |
---|
674 | "Number of Units Transference for the Whole Heat Exchanger" |
---|
675 | Thermal.NTU = max([HotSide.HeatTransfer.NTU,ColdSide.HeatTransfer.NTU]); |
---|
676 | |
---|
677 | "Number of Units Transference for Hot Side" |
---|
678 | HotSide.HeatTransfer.NTU*HotSide.HeatTransfer.WCp = Thermal.Ud*Atotal; |
---|
679 | |
---|
680 | "Number of Units Transference for Cold Side" |
---|
681 | ColdSide.HeatTransfer.NTU*ColdSide.HeatTransfer.WCp = Thermal.Ud*Atotal; |
---|
682 | |
---|
683 | if Thermal.Cr equal 1 # To be Fixed: Effectiveness in true counter flow ! |
---|
684 | |
---|
685 | then |
---|
686 | "Effectiveness in Counter Flow" |
---|
687 | Thermal.Eft = Thermal.NTU/(1+Thermal.NTU); |
---|
688 | |
---|
689 | "LMTD Correction Factor" |
---|
690 | Thermal.Fc =Thermal.Eft/(1-Thermal.Eft)/Thermal.NTU; |
---|
691 | |
---|
692 | else |
---|
693 | "Effectiveness in Counter Flow" |
---|
694 | Thermal.Eft = (1-exp(-Thermal.NTU*(1-Thermal.Cr)))/(1-Thermal.Cr*exp(-Thermal.NTU*(1-Thermal.Cr))); |
---|
695 | |
---|
696 | "LMTD Correction Factor" |
---|
697 | Thermal.Fc =(ln(abs(1-Thermal.Eft*Thermal.Cr))-ln(abs(1-Thermal.Eft)))/(Thermal.NTU*(1-Thermal.Cr)); |
---|
698 | |
---|
699 | end |
---|
700 | end |
---|