source: branches/gui/eml/heat_exchangers/HEX_Engine.mso @ 803

#*-------------------------------------------------------------------
* 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.
*--------------------------------------------------------------------
* Author: Gerson Balbueno Bicca 
* $Id: HEX_Engine.mso 739 2009-02-27 22:18:32Z bicca $
*--------------------------------------------------------------------*#

using "streams";

Model Properties_Average
        
ATTRIBUTES
        Pallete = false;
        Brief = "Average physical properties of the streams.";
        Info =
        "to be documented.";
        
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=2e4, DisplayUnit='kPa');
rho             as dens_mass            (Brief="Stream Density" ,Default=1000, Lower=1e-3, Upper=5e5, Symbol = "\rho");
Mu              as viscosity            (Brief="Stream Viscosity",Lower=0.0001, Symbol = "\mu");
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
        
ATTRIBUTES
        Pallete = false;
        Brief = "Inlet and outlet physical properties of the streams.";
        Info =
        "to be documented.";
        
VARIABLES
Fw              as flow_mass            (Brief="Stream Mass Flow");
rho             as dens_mass            (Brief="Stream Density" ,Default=1000, Lower=1e-3, Upper=5e5, Symbol = "\rho");
end

Model Properties_Wall
        
ATTRIBUTES
        Pallete = false;
        Brief = "Physical properties of the streams at wall temperature.";
        Info =
        "to be documented.";
        
VARIABLES

Mu              as viscosity            (Brief="Stream Viscosity",Default=1, Lower=1e-5, Upper=1e5, Symbol = "\mu");
Twall           as temperature  (Brief="Wall Temperature",Lower=50);

end

Model Physical_Properties
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
VARIABLES

Inlet           as Properties_In_Out    (Brief="Properties at Inlet Stream", Symbol = "_{in}");
Average         as Properties_Average   (Brief="Properties at Average Temperature", Symbol = "_{avg}");
Outlet          as Properties_In_Out    (Brief="Properties at Outlet Stream", Symbol = "_{out}");
Wall                    as Properties_Wall              (Brief="Properties at Wall Temperature", Symbol = "_{wall}");

end

Model Physical_Properties_Heatex
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
VARIABLES

Mw              as molweight                    (Brief="Average Mol Weight",Default=75, Lower=1, Upper=1e8);
Cp              as cp_mol                               (Brief="Average Molar Heat Capacity", Upper=1e10);
Inlet   as Properties_In_Out    (Brief="Properties at Inlet Stream", Symbol = "_{in}");
Outlet  as Properties_In_Out    (Brief="Properties at Outlet Stream", Symbol = "_{out}");

end

Model Tube_Pdrop
        
ATTRIBUTES
        Pallete = false;
        Brief = "Pressure drop and velocities in the tube side section of a shell and tube heat exchanger.";
        
VARIABLES
TubeFriction    as press_delta  (Brief="Tube Pressure Drop due to friction", Symbol = "\Delta P_{tube}", Default=0.01, Lower=1E-10,DisplayUnit='kPa');
InletNozzle     as press_delta  (Brief="Inlet Nozzle Pressure Drop", Symbol = "\Delta P_{Nozzle\_In}", Default=0.01, Lower=0,DisplayUnit='kPa');
OutletNozzle    as press_delta  (Brief="Outlet Nozzle Pressure Drop", Symbol = "\Delta P_{Nozzle\_Out}", Default=0.01, Lower=0,DisplayUnit='kPa');
Total                           as press_delta  (Brief="Total Pressure Drop", Symbol = "\Delta P_{total}", Default=0.01, Lower=1E-10,DisplayUnit='kPa');
Vnozzle_in              as velocity             (Brief="Inlet Nozzle Velocity", Symbol = "V_{Nozzle\_In}", Default=1, Upper=1e5, Lower=0);
Vnozzle_out     as velocity             (Brief="Outlet Nozzle Velocity", Symbol = "V_{Nozzle\_Out}", Default=1, Upper=1E5, Lower=0);
FricFactor              as fricfactor           (Brief="Friction Factor", Symbol = "f_i", Default=0.05, Lower=1e-10, Upper=2000);

EQUATIONS
"Total Pressure Drop"
        Total = TubeFriction + InletNozzle + OutletNozzle;

end

Model Tube_Heat_Transfer
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
VARIABLES
Re              as positive                             (Brief="Tube Side Reynolds Number",Default=1000,Lower=1);
Nu              as positive                             (Brief="Nusselt Number",Default=0.5,Lower=1e-8);
htube   as heat_trans_coeff (Brief="Tube Side Film Coefficient",Default=1,Lower=1e-12, Upper=1e6);
fi              as fricfactor                   (Brief="Friction Factor", Default=0.05, Lower=1e-10, Upper=2000);
PR              as positive                             (Brief="Tube Side Prandtl Number",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
        
ATTRIBUTES
        Pallete = false;
        Brief = "Pressure drop and velocities in the shell side section of a shell and tube heat exchanger.";
        
VARIABLES
Ideal                           as press_delta          (Brief="Ideal Pressure Drop", Symbol = "\Delta P_{ideal}", Default=0.01, Lower=0,DisplayUnit='kPa');
CrossFlow                       as press_delta          (Brief="Cross Flow Pressure Drop", Symbol = "\Delta P_{CrossFlow}", Default=0.01, Lower=0,DisplayUnit='kPa');
EndZones                        as press_delta          (Brief="End Zones Pressure Drop", Symbol = "\Delta P_{EndZones}", Default=0.01, Lower=0,DisplayUnit='kPa');
Window                                  as press_delta          (Brief="Window Pressure Drop", Symbol = "\Delta P_{Window}", Default=0.01, Lower=1e-10,DisplayUnit='kPa');
InletNozzle             as press_delta          (Brief="Inlet Nozzle Pressure Drop", Symbol = "\Delta P_{Nozzle\_In}", Default=0.01, Lower=0,DisplayUnit='kPa');
OutletNozzle            as press_delta          (Brief="Outlet Nozzle Pressure Drop", Symbol = "\Delta P_{Nozzle\_Out}", Default=0.01, Lower=0,DisplayUnit='kPa');
Total                                   as press_delta          (Brief="Total Pressure Drop", Symbol = "\Delta P_{Total}", Default=0.01, Lower=0,DisplayUnit='kPa');
FricFactor              as fricfactor                   (Brief="Friction Factor",  Symbol = "f_i", Default=0.05, Lower=1e-10, Upper=2000);
Vnozzle_in                      as velocity                     (Brief="Inlet Nozzle Velocity", Symbol = "V_{Nozzle\_In}", Default=1, Upper=1e5, Lower=0);
Vnozzle_out             as velocity                     (Brief="Outlet Nozzle Velocity", Symbol = "V_{Nozzle\_Out}", 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"
        Total = CrossFlow+ EndZones + InletNozzle + OutletNozzle + Window;

end

Model Shell_Heat_Transfer
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
VARIABLES
Re              as positive                             (Brief="Shell Side Reynolds Number",Default=100,Lower=1E-6);
PR              as positive                             (Brief="Shell Side Prandtl Number",Default=0.7,Lower=1e-6);
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);
end

Model Baffles_Main
        
ATTRIBUTES
        Pallete = false;
        Brief = "Main variables in the Baffle section of a shell and tube heat exchanger.";

PARAMETERS

BaffleCut                       as Integer      (Brief="Baffle Cut",Default=25,Lower=25);
NumberOfBaffles     as Real             (Brief="Number of Baffles", Symbol = "N_{baffles}", Lower=1);

VARIABLES

Inlet_Spacing                   as length               (Brief="Inlet Baffle Spacing",Lower=1e-8, Symbol = "L_{si}", DisplayUnit ='mm' );
Central_Spacing                 as length               (Brief="Central Baffle Spacing",Lower=1e-8, Symbol = "L_s", DisplayUnit ='mm' );
Outlet_Spacing          as length               (Brief="Outlet Baffle Spacing",Lower=1e-8, Symbol = "L_{so}", DisplayUnit ='mm' );

end

Model Clearances_Main
        
ATTRIBUTES
        Pallete = false;
        Brief = "Main parameters for diametral clearances in a shell and tube heat exchanger.";

PARAMETERS

SealStrip                               as Integer      (Brief="Number of Sealing Strips pairs",Lower=1);
Hinozzle_Shell          as length               (Brief="Height Under Shell Inlet Nozzle",Lower=1E-6);
Honozzle_Shell          as length               (Brief="Height Under Shell Outlet Nozzle",Lower=1E-6);
BundleToShell           as length               (Brief="Bundle-to-Shell Clearance", Symbol = "L_{cf}", Lower=1E-8);
BaffleToShell           as length       (Brief="Baffle-to-Shell Clearance", Symbol = "L_{cd}", Lower=1E-8);
TubeToBaffle            as length       (Brief="Tube-to-Baffle Clearance", Symbol = "L_{td}", Lower=1E-8);

end

Model NTU_Basic

ATTRIBUTES
        Pallete = false;
        Brief = "Number of Units Transference Method.";
        Info =
        "to be documented";

VARIABLES

Ch              as positive     (Brief="Hot Stream Heat Capacity",Lower=1e-3,Default=1e3,Unit='W/K',Protected=true);
Cc              as positive     (Brief="Cold Stream Heat Capacity",Lower=1e-3,Default=1e3,Unit='W/K',Protected=true);
Cr              as positive     (Brief="Heat Capacity Ratio",Default=0.5,Lower=1e-6,Protected=true);
Cmin    as positive     (Brief="Minimum Heat Capacity",Lower=1e-10,Default=1e3,Unit='W/K',Protected=true);
Cmax    as positive     (Brief="Maximum Heat Capacity",Lower=1e-10,Default=1e3,Unit='W/K',Protected=true);
NTU             as positive     (Brief="Number of Units Transference",Default=0.05,Lower=1e-10,Protected=true);
Eft             as positive     (Brief="Effectiveness",Default=0.5,Lower=1e-8,Upper=1, Symbol ="\varepsilon",Protected=true);
Eft1            as positive     (Brief="Effectiveness Correction",Lower=1e-8,Default=0.5, Symbol ="\hat {\varepsilon}",Protected=true);

end

Model LMTD_Basic

ATTRIBUTES
        Pallete = false;
        Brief = "Log Mean Temperature Difference Method.";
        Info =
        "This model should be used as submodel when the LMTD needs to be calculating";
        
VARIABLES

DT0             as temp_delta   (Brief="Temperature Difference at Inlet",Lower=1e-6, Symbol ="\Delta T_0",Protected=true);
DTL             as temp_delta   (Brief="Temperature Difference at Outlet",Lower=1e-6, Symbol ="\Delta T_L",Protected=true);
LMTD    as temp_delta   (Brief="Logarithmic Mean Temperature Difference",Lower=1e-6,Protected=true);
Fc                      as positive             (Brief="LMTD Correction Factor",Lower=0.1,Protected=true);

EQUATIONS

if abs(DT0 - DTL) > 0.05*max(abs([DT0,DTL])) 
        
        then
"Log Mean Temperature Difference"
        LMTD= (DT0-DTL)/ln(DT0/DTL);

        else
        
if DT0*DTL equal 0
        
        then
"Log Mean Temperature Difference"
        LMTD = 0.5*(DT0+DTL);
        
        else
"Log Mean Temperature Difference"
        LMTD = 0.5*(DT0+DTL)*(1-(DT0-DTL)^2/(DT0*DTL)*(1+(DT0-DTL)^2/(DT0*DTL)/2)/12);
        
end
        
end

end

Model Details_Main
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
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);

end

Model Tube_Side_Main

ATTRIBUTES
        Pallete = false;
        Brief = "Main variables in the Tube Side section of a shell and tube heat exchanger.";

PARAMETERS

NumberOfTubes           as Integer                      (Brief="Total Number of Tubes in Shell",Default=100,Lower=1);
Tubepasses                      as Integer                      (Brief="Number of Tube Passes", Lower=1);
TubeLength                              as length                               (Brief="Effective Tube Length",Lower=0.1);
TubePitch                               as length                               (Brief="Tube Pitch",Lower=1E-8);
Kwall                                           as conductivity         (Brief="Tube Wall Material Thermal Conductivity");
TubeOD                                          as length                               (Brief="Tube Outside Diameter",Lower=1E-6);
TubeID                                  as length                               (Brief="Tube Inside Diameter",Lower=1E-6);
Fouling                                 as positive                     (Brief="Tubeside Fouling Resistance",Unit='m^2*K/kW', Symbol = "Rf_{tube}", Default=1E-6 , Lower=0);
InletNozzleID           as length                               (Brief="Inlet Nozzle Inside Diameter", Lower=1E-6);
OutletNozzleID                  as length                               (Brief="Outlet Nozzle Inside Diameter", Lower=1E-6);

VARIABLES

PressureDrop    as Tube_Pdrop                           (Brief="Tube Side Pressure Drop", Symbol = " ");
HeatTransfer    as Tube_Heat_Transfer   (Brief="Tube Side Heat Transfer", Symbol = " ");
Properties              as Physical_Properties          (Brief="Tube Side Properties", Symbol = " ");

end

Model Shell_Side_Main
        
ATTRIBUTES
        Pallete = false;
        Brief = "Main variables in the Shell Side section of a shell and tube heat exchanger.";

PARAMETERS

ShellID                         as length               (Brief="Inside Shell Diameter",Lower=1E-6);
Fouling                         as positive     (Brief="Shellside Fouling Resistance",Unit='m^2*K/kW', Symbol = "Rf_{shell}", Default=1E-6 , Lower=0);
InletNozzleID   as length               (Brief="Inlet Nozzle Inside Diameter", Lower=1E-6);
OutletNozzleID          as length               (Brief="Outlet Nozzle Inside Diameter", Lower=1E-6);

VARIABLES

PressureDrop    as Shell_Pdrop                                  (Brief="Shell Side Pressure Drop", Symbol = " ");
HeatTransfer    as Shell_Heat_Transfer          (Brief= "Shell Side Heat Transfer", Symbol = " ");
Properties              as Physical_Properties          (Brief="ShellSide Properties", Symbol = " ");

end

Model DoublePipe_HeatTransfer
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
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);
fi              as fricfactor                   (Brief="Friction Factor", Default=0.05, Lower=1e-10, Upper=2000);
Nu              as positive                             (Brief="Nusselt Number",Default=0.5,Lower=1e-8);
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
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
PARAMETERS

Dh      as length               (Brief="Hydraulic Diameter of Pipe for Pressure Drop",Lower=1e-6);

VARIABLES

Pdrop   as press_delta  (Brief="Total Pressure Drop",Default=0.01, Lower=0,DisplayUnit='kPa', Symbol ="\Delta P");
Pd_fric as press_delta  (Brief="Pressure Drop for friction",Default=0.01, Lower=0,DisplayUnit='kPa', Symbol ="\Delta P_{fric}");
Pd_ret  as press_delta  (Brief="Pressure Drop due to return",Default=0.01, Lower=0,DisplayUnit='kPa', Symbol ="\Delta P_{return}");
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
        
ATTRIBUTES
        Pallete = false;
        Brief = "to be documented";
        Info =
        "to be documented";
        
VARIABLES

HeatTransfer    as DoublePipe_HeatTransfer      (Brief="Double Pipe Heat Transfer",Symbol=" ");
PressureDrop    as DoublePipe_PressureDrop      (Brief="Double Pipe Pressure Drop", Symbol=" ");
Properties      as Physical_Properties                  (Brief="Double Pipe Properties",Symbol=" " );

end