#*------------------------------------------------------------------- * EMSO Model Library (EML) Copyright (C) 2004 - 2007 ALSOC. * * This LIBRARY is free software; you can distribute it and/or modify * it under the therms of the ALSOC FREE LICENSE as available at * http://www.enq.ufrgs.br/alsoc. * * EMSO Copyright (C) 2004 - 2007 ALSOC, original code * from http://www.rps.eng.br Copyright (C) 2002-2004. * All rights reserved. * * EMSO is distributed under the therms of the ALSOC LICENSE as * available at http://www.enq.ufrgs.br/alsoc. * *--------------------------------------------------------------------* * Heat Exchangers Abstract Models *-------------------------------------------------------------------- * - Inlet_Main_Stream : Inlet Streams *-------------------------------------------------------------------- * - Hot : Inlet Hot Stream * - Cold : Inlet Cold Stream *-------------------------------------------------------------------- * - Outlet_Main_Stream : Outlet Streams *-------------------------------------------------------------------- * - Hot : Outlet Hot Stream * - Cold : Outlet Cold Stream *-------------------------------------------------------------------- * - Main_Properties : Physical Properties for Hot and Cold Side *-------------------------------------------------------------------- * Physical_Properties * Properties_In_Out : Inlet/Outlet Physical Properties * Properties_Average : Average Physical Properties * Properties_Wall : Physical Properties at Wall Temperature *-------------------------------------------------------------------- * - Tube_Side_Main : Tube Side Main Variables *---------------------------------------------------------------------- * Tube_Pdrop : Tube Side Pressure Drop * Tube_Heat_Transfer : Tube Side Heat Transfer *---------------------------------------------------------------------- * - Shell_Side_Main : Shell Side Main Variables *---------------------------------------------------------------------- * Shell_Pdrop : Shell Side Pressure Drop * Shell_Heat_Transfer : Shell Side Heat Transfer *---------------------------------------------------------------------- * - Baffles_Main : Baffles Spacing *---------------------------------------------------------------------- * - Main_Resistances : Thermal Resistances *---------------------------------------------------------------------- * - Details_Main : Heat Exchanger Thermal Details *---------------------------------------------------------------------- * - Main_Pdrop : Heat Exchanger Pressure Drop (Simplified) * Basic_Pdrop : Hot and Cold Side Pressure Drop *---------------------------------------------------------------------- * - Main_DoublePipe : Double Pipe Heat Exchanger Block * DoublePipe_HeatTransfer * DoublePipe_PressureDrop *---------------------------------------------------------------------- * Author: Gerson Balbueno Bicca * $Id: HEX_Engine.mso 110 2007-01-12 18:44:02Z bicca $ *--------------------------------------------------------------------*# using "streams"; Model Inlet_Main_Stream #===================================================================== # Inlet Streams #===================================================================== VARIABLES Hot as stream; # Inlet Hot Stream Cold as stream; # Inlet Cold Stream end Model Outlet_Main_Stream #===================================================================== # Outlet Streams #===================================================================== VARIABLES Hot as stream_therm; # Outlet Hot Stream Cold as stream_therm; # Outlet Cold Stream end #===================================================================== # Heat Exchangers Physical Properties #===================================================================== Model Properties_Average #===================================================================== # Average Physical Properties #===================================================================== VARIABLES Mw as molweight (Brief="Average Mol Weight",Default=75, Lower=1, Upper=1e8); T as temperature (Brief="Average Temperature",Lower=50); P as pressure (Brief="Average Pressure",Default=1, Lower=1e-10, Upper=30); rho as dens_mass (Brief="Stream Density" ,Default=1000, Lower=1e-3, Upper=5e5); Mu as viscosity (Brief="Stream Viscosity",Lower=0.0001); Cp as cp_mol (Brief="Stream Molar Heat Capacity", Upper=1e10); K as conductivity (Brief="Stream Thermal Conductivity", Default=1.0, Lower=1e-5, Upper=500); end Model Properties_In_Out #===================================================================== # Inlet/Outlet Physical Properties #===================================================================== VARIABLES Fw as flow_mass (Brief="Stream Mass Flow"); rho as dens_mass (Brief="Stream Density" ,Default=1000, Lower=1e-3, Upper=5e5); Mu as viscosity (Brief="Stream Viscosity",Default=1, Lower=1e-5, Upper=1e5); Cp as cp_mol (Brief="Stream Molar Heat Capacity", Upper=1e10); K as conductivity (Brief="Stream Thermal Conductivity", Default=1.0, Lower=1e-5, Upper=500); end Model Properties_Wall #===================================================================== # Physical Properties at Wall Temperature #===================================================================== VARIABLES Mu as viscosity (Brief="Stream Viscosity",Default=1, Lower=1e-5, Upper=1e5); Cp as cp_mol (Brief="Stream Molar Heat Capacity", Upper=1e10); K as conductivity (Brief="Stream Thermal Conductivity", Default=1.0, Lower=1e-5, Upper=500); Twall as temperature (Brief="Wall Temperature",Lower=50); end Model Physical_Properties #===================================================================== # Physical Properties #===================================================================== VARIABLES Inlet as Properties_In_Out; # Properties at Inlet Stream Average as Properties_Average; # Properties at Average Temperature Outlet as Properties_In_Out; # Properties at Outlet Stream Wall as Properties_Wall; # Properties at Wall Temperature end Model Main_Properties #===================================================================== # Physical Properties for Hot and Cold Side #===================================================================== VARIABLES Hot as Physical_Properties; # Hot Stream Cold as Physical_Properties; # Cold Stream end Model Tube_Pdrop #===================================================================== # Tube Side Pressure Drop block #===================================================================== VARIABLES PdTube as press_delta (Brief="Tube Pressure Drop",Default=0.01, Lower=1e-10); Pdtotal as press_delta (Brief="Total Pressure Drop",Default=0.01, Lower=1e-10); Pdnozzle_in as press_delta (Brief="Inlet Nozzle Pressure Drop",Default=0.01, Lower=0); Pdnozzle_out as press_delta (Brief="Outlet Nozzle Pressure Drop",Default=0.01, Lower=0); Vnozzle_in as velocity (Brief="Inlet Nozzle Velocity",Default=1, Upper=1e5, Lower=0); Vnozzle_out as velocity (Brief="Outlet Nozzle Velocity",Default=1, Upper=1e5, Lower=0); EQUATIONS "Total Pressure Drop" Pdtotal = PdTube + Pdnozzle_in + Pdnozzle_out; end Model Tube_Heat_Transfer #===================================================================== # Tube Side Heat Transfer Block #===================================================================== VARIABLES Re as positive (Brief="Tube Side Reynolds Number",Default=1000,Lower=1); htube as heat_trans_coeff (Brief="Tube Side Film Coefficient",Default=1,Lower=1e-12, Upper=1e6); PR as positive (Brief="Tube Side Prandtl Number",Default=0.5,Lower=1e-8); PRw as positive (Brief="Tube Side Prandtl Number at Wall Temperature",Default=0.5,Lower=1e-8); Phi as positive (Brief="Phi Correction",Default=1,Lower=1e-3); Vtube as velocity (Brief="Tube Side Velocity",Lower=1e-8); end Model Shell_Pdrop #===================================================================== # Shell Side Pressure Drop block #===================================================================== VARIABLES PdCross as press_delta (Brief="Cross Flow Pressure Drop",Default=0.01, Lower=0); PdEndZones as press_delta (Brief="End Zones Pressure Drop",Default=0.01, Lower=0); Pdwindow as press_delta (Brief="Window Pressure Drop",Default=0.01, Lower=1e-10); Pdtotal as press_delta (Brief="Total Pressure Drop",Default=0.01, Lower=0); Pdnozzle_in as press_delta (Brief="Inlet Nozzle Pressure Drop",Default=0.01, Lower=0); Pdnozzle_out as press_delta (Brief="Outlet Nozzle Pressure Drop",Default=0.01, Lower=0); Vnozzle_in as velocity (Brief="Inlet Nozzle Velocity",Default=1, Upper=1e5, Lower=0); Vnozzle_out as velocity (Brief="Outlet Nozzle Velocity",Default=1, Upper=1e5, Lower=0); RVsquare_out as positive (Brief = "Outlet Nozzle rho-V^2", Default=1, Upper=1e6, Unit = "kg/s^2/m"); RVsquare_in as positive (Brief = "Inlet Nozzle rho-V^2", Default=1, Upper=1e6, Unit = "kg/s^2/m"); EQUATIONS "Shell Side Total Pressure Drop" Pdtotal = PdCross + PdEndZones + Pdnozzle_in + Pdnozzle_out + Pdwindow; end Model Shell_Heat_Transfer #===================================================================== # Shell Side Heat Transfer Block #===================================================================== VARIABLES Re as positive (Brief="Shell Side Reynolds Number",Default=100,Lower=1); PR as positive (Brief="Shell Side Prandtl Number",Default=0.7,Lower=1e-6); PRw as positive (Brief="Shell Side Prandtl Number",Default=0.5,Lower=1e-8); hshell as heat_trans_coeff (Brief="Shell Side Film Coefficient",Default=1,Lower=1e-12, Upper=1e6); Phi as positive (Brief="Phi Correction",Default=1,Lower=1e-3); Ji as constant (Brief="Shell Side Ji Factor",Default=0.05); Jr as positive (Brief="Shell Side Jr Factor",Lower=10e-6); Jl as positive (Brief="Shell Side Jl Factor",Lower=10e-6); Jb as positive (Brief="Shell Side Jb Factor",Lower=10e-6); Jc as positive (Brief="Shell Side Jc Factor",Lower=10e-6); Js as positive (Brief="Shell Side Js Factor",Lower=10e-6); Jtotal as positive (Brief="Shell Side Jtotal Factor",Lower=10e-6); Sm as area (Brief="Shell Side Cross Flow Area",Default=0.05,Lower=10e-6); end Model Baffles_Main #===================================================================== # Baffles Spacing #===================================================================== VARIABLES Ls as length (Brief="Central Baffle Spacing",Lower=1e-8); Lsi as length (Brief="Inlet Baffle Spacing",Lower=1e-8); Lso as length (Brief="Outlet Baffle Spacing",Lower=1e-8); end Model Main_Resistances #===================================================================== # Resistances #===================================================================== VARIABLES Rtube as positive (Brief="Tube Resistance",Unit="m^2*K/kW",Lower=1e-6); Rwall as positive (Brief="Wall Resistance",Unit="m^2*K/kW",Lower=1e-6); Rshell as positive (Brief="Shell Resistance",Unit="m^2*K/kW",Lower=1e-6); Rfi as positive (Brief="Inside Fouling Resistance",Unit="m^2*K/kW",Default=1e-6,Lower=0); Rfo as positive (Brief="Outside Fouling Resistance",Unit="m^2*K/kW",Default=1e-6,Lower=0); end Model Details_Main #===================================================================== # Heat Exchanger Thermal Details #===================================================================== VARIABLES A as area (Brief="Exchange Surface Area"); Q as power (Brief="Heat Transfer", Default=7000, Lower=1e-6, Upper=1e10); Uc as heat_trans_coeff (Brief="Overall Heat Transfer Coefficient Clean",Default=1,Lower=1e-6,Upper=1e10); Ud as heat_trans_coeff (Brief="Overall Heat Transfer Coefficient Dirty",Default=1,Lower=1e-6,Upper=1e10); Ch as positive (Brief="Hot Stream Heat Capacity",Lower=1e-3,Default=1e3,Unit="W/K"); Cc as positive (Brief="Cold Stream Heat Capacity",Lower=1e-3,Default=1e3,Unit="W/K"); Cr as positive (Brief="Heat Capacity Ratio",Default=0.5,Lower=1e-6); Cmin as positive (Brief="Minimum Heat Capacity",Lower=1e-10,Default=1e3,Unit="W/K"); Cmax as positive (Brief="Maximum Heat Capacity",Lower=1e-10,Default=1e3,Unit="W/K"); NTU as positive (Brief="Number of Units Transference",Default=0.05,Lower=1e-10); EQUATIONS "Number of Units Transference" NTU*Cmin = Ud*A; end Model Tube_Side_Main #===================================================================== # Tube Side Main Variables #===================================================================== VARIABLES PressureDrop as Tube_Pdrop; #Tube Side Pressure Drop HeatTransfer as Tube_Heat_Transfer; #Tube Side Heat Transfer end Model Shell_Side_Main #===================================================================== # Shell Side Main Variables #===================================================================== VARIABLES PressureDrop as Shell_Pdrop; # Shell Side Pressure Drop HeatTransfer as Shell_Heat_Transfer; # Shell Side Heat Transfer end Model Basic_Pdrop #===================================================================== # Pressure Drop #===================================================================== VARIABLES Pdrop as press_delta (Brief="Pressure Drop",Default=0.01, Lower=0); FPdrop as Real (Brief="Pressure Drop : Fraction of Inlet",Lower=0,Upper=0.8); end Model Main_Pdrop #===================================================================== # Pressure Drop block #===================================================================== VARIABLES Hot as Basic_Pdrop;# Hot Stream Cold as Basic_Pdrop;# Cold Stream end Model DoublePipe_HeatTransfer #===================================================================== # Double Pipe Heat Transfer Block #===================================================================== PARAMETERS As as area (Brief="Cross Sectional Area for Flow",Default=0.05,Lower=1e-8); Dh as length (Brief="Hydraulic Diameter of Pipe for Heat Transfer",Lower=1e-8); VARIABLES Re as positive (Brief="Reynolds Number",Default=100,Lower=1); hcoeff as heat_trans_coeff (Brief="Film Coefficient",Default=1,Lower=1e-12, Upper=1e6); PR as positive (Brief="Prandtl Number",Default=0.5,Lower=1e-8); Phi as positive (Brief="Phi Correction",Default=1,Lower=1e-3); Vmean as velocity (Brief="Tube Velocity",Lower=1e-8); end Model DoublePipe_PressureDrop #===================================================================== # # Double Pipe Pressure Drop Block #===================================================================== PARAMETERS Dh as length (Brief="Hydraulic Diameter of Pipe for Pressure Drop",Lower=1e-6); VARIABLES Pdrop as press_delta (Brief="Pressure Drop",Default=0.01, Lower=1e-10); fi as fricfactor (Brief="Friction Factor", Default=0.05, Lower=1e-10, Upper=2000); Re as positive (Brief="Reynolds Number",Default=100,Lower=1); end Model Main_DoublePipe #===================================================================== # Double Pipe Main Variables #===================================================================== VARIABLES HeatTransfer as DoublePipe_HeatTransfer; PressureDrop as DoublePipe_PressureDrop; end