| 1 | #*--------------------------------------------------------------------- |
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| 2 | * Model of a Multistream Heat Exchanger |
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| 3 | * |
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| 4 | * Streams: |
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| 5 | * * Inlet(Ninlet) streams .... at least one material stream |
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| 6 | * * Outlet stream .... one material stream |
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| 7 | * |
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| 8 | * Purpose: |
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| 9 | * * Determines thermal and phase conditions of outlet stream |
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| 10 | * |
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| 11 | *---------------------------------------------------------------------- |
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| 12 | * Author: Gerson Balbueno Bicca |
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| 13 | * $Id: Mheatex.mso 45 2006-11-07 16:11:10Z bicca $ |
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| 14 | *--------------------------------------------------------------------*# |
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| 15 | |
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| 16 | using "streams.mso"; |
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| 17 | |
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| 18 | Model Inlet_Main_Stream |
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| 19 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 20 | # Inlet Streams |
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| 21 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 22 | PARAMETERS |
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| 23 | |
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| 24 | Ncold as Integer (Brief="Number of Inlet Cold Streams",Lower=1); |
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| 25 | Nhot as Integer (Brief="Number of Inlet Hot Streams",Lower=1); |
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| 26 | |
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| 27 | VARIABLES |
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| 28 | |
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| 29 | Hot (Nhot) as stream;# Inlet Hot Streams |
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| 30 | Cold (Ncold) as stream;# Inlet Cold Streams |
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| 31 | |
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| 32 | end |
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| 33 | |
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| 34 | Model Outlet_Main_Stream |
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| 35 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 36 | # Outlet Streams |
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| 37 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 38 | PARAMETERS |
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| 39 | |
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| 40 | Ncold as Integer (Brief="Number of Inlet Cold Streams",Lower=1); |
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| 41 | Nhot as Integer (Brief="Number of Inlet Hot Streams",Lower=1); |
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| 42 | |
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| 43 | VARIABLES |
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| 44 | |
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| 45 | Hot (Nhot) as stream_therm;# Outlet Hot Streams |
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| 46 | Cold (Ncold) as stream_therm;# Outlet Cold Streams |
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| 47 | |
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| 48 | end |
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| 49 | |
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| 50 | Model Mheatex |
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| 51 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 52 | # Multistream Heat Exchanger Basic Calculation |
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| 53 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 54 | PARAMETERS |
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| 55 | |
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| 56 | ext PP as CalcObject (Brief="Physical Properties"); |
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| 57 | ext NComp as Integer (Brief="Number of Components"); |
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| 58 | HE as CalcObject (Brief="Cold Box Calculations",File="heatex"); |
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| 59 | Side as Integer (Brief="Flow Direction",Lower=0,Upper=1); |
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| 60 | Ncold as Integer (Brief="Number of Inlet Cold Streams",Lower=1); |
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| 61 | Nhot as Integer (Brief="Number of Inlet Hot Streams",Lower=1); |
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| 62 | |
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| 63 | VARIABLES |
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| 64 | |
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| 65 | in Inlet as Inlet_Main_Stream; # Inlet Hot Streams |
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| 66 | out Outlet as Outlet_Main_Stream; # Outlet Hot Streams |
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| 67 | |
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| 68 | Q as power (Brief="Heat Transfer"); |
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| 69 | LMTD as temp_delta (Brief="Logarithmic Mean Temperature Difference"); |
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| 70 | UA as positive (Unit="W/K"); |
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| 71 | |
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| 72 | SET |
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| 73 | |
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| 74 | Side = HE.FlowDir(); |
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| 75 | |
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| 76 | Inlet.Ncold = Ncold; |
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| 77 | Outlet.Ncold = Ncold; |
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| 78 | |
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| 79 | Inlet.Nhot = Nhot ; |
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| 80 | Outlet.Nhot = Nhot ; |
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| 81 | |
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| 82 | |
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| 83 | EQUATIONS |
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| 84 | |
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| 85 | "Hot Flow" |
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| 86 | Outlet.Hot.F = Inlet.Hot.F; |
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| 87 | |
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| 88 | "Cold Flow" |
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| 89 | Outlet.Cold.F = Inlet.Cold.F; |
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| 90 | |
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| 91 | "Hot Composition" |
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| 92 | Outlet.Hot.z = Inlet.Hot.z; |
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| 93 | |
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| 94 | "Cold Composition" |
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| 95 | Outlet.Cold.z = Inlet.Cold.z; |
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| 96 | |
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| 97 | "Vapourisation Fraction Hot Stream" |
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| 98 | Outlet.Hot.v = Inlet.Hot.v; |
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| 99 | |
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| 100 | "Vapourisation Fraction Cold Stream" |
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| 101 | Outlet.Cold.v = Inlet.Cold.v; |
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| 102 | |
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| 103 | "Heat Duty Hot Stream" |
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| 104 | Q = sum(Inlet.Hot.F*(Inlet.Hot.h- Outlet.Hot.h)); |
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| 105 | |
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| 106 | "Heat Duty Cold Stream" |
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| 107 | Q = -sum(Inlet.Cold.F*(Inlet.Cold.h- Outlet.Cold.h)); |
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| 108 | |
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| 109 | "Heat Duty" |
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| 110 | Q=UA*LMTD; |
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| 111 | |
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| 112 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 113 | # Flow Direction |
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| 114 | #+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++# |
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| 115 | |
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| 116 | if Side equal 0 |
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| 117 | |
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| 118 | then |
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| 119 | "Cocurrent Flow LMTD" |
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| 120 | LMTD = HE.CocurrentLMTD(max(Inlet.Hot.T),min(Outlet.Hot.T),min(Inlet.Cold.T),max(Outlet.Cold.T)); |
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| 121 | |
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| 122 | else |
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| 123 | "Counter Flow LMTD" |
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| 124 | LMTD = HE.CounterLMTD(max(Inlet.Hot.T),min(Outlet.Hot.T),max(Inlet.Cold.T),min(Outlet.Cold.T)); |
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| 125 | |
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| 126 | end |
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| 127 | |
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| 128 | end |
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