source: trunk/eml/pressure_changers/turbine.mso @ 753

#*-------------------------------------------------------------------
* 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.
*
*----------------------------------------------------------------------
* Authors: Andrey Copat, Estefane S. Horn, Marcos L. Alencastro
* $Id: turbine.mso 372 2007-09-21 22:17:36Z arge $
*--------------------------------------------------------------------*#

using "streams";

Model Hidraulic_Turbine
        ATTRIBUTES
        Pallete         = true;
        Icon            = "icon/HidraulicTurbine"; 
        Brief           = "Model of a Hidraulic Turbine.";
        Info            =
"== Assumptions ==
* Steady State;
* Only Liquid;
* Adiabatic;
* Isentropic.
        
== Specify ==
* the inlet stream;
* the Pressure Increase (Pdiff) OR the outlet pressure (Outlet.P);
* the Turbine efficiency (Eff);
* the Brake efficiency (Meff);
* the Volumetric expansivity (Beta).
";
        
        PARAMETERS
outer NComp     as Integer                      (Brief = "Number of chemical components", Lower = 1);
outer PP                as Plugin                       (Brief = "External Physical Properties", Type="PP");
        Mw(NComp)       as molweight            (Brief = "Molar Weight");
        
        VARIABLES
        Eff     as efficiency           (Brief = "Turbine efficiency");
        Meff    as efficiency           (Brief = "Brake efficiency");
        Beta    as positive             (Brief = "Volumetric expansivity", Unit = '1/K');
        Head    as head                         (Brief = "Head Developed");
        FPower  as power                        (Brief = "Fluid Power");
        BPower  as power                        (Brief = "Brake Power");
        EPower  as power                        (Brief = "Eletrical Potency");
        Pratio  as positive                     (Brief = "Pressure Ratio");
        Pdrop   as press_delta          (Brief = "Pressure Drop", DisplayUnit = 'kPa', Symbol ="\Delta P");
        Mwm     as molweight            (Brief = "Mixture Molar Weight");
        rho             as dens_mass            (Brief = "Specific Mass");
        Cp              as cp_mol                       (Brief = "Heat Capacity");
in      Inlet   as stream                       (Brief = "Inlet stream", PosX=0, PosY=0.5086, Symbol="_{in}");
out     Outlet  as stream                       (Brief = "Outlet stream", PosX=1, PosY=0.5022, Symbol="_{out}");

        SET
        Mw = PP.MolecularWeight();      
        
        EQUATIONS
        #Mixtures Properties
        "Calculate Mwm for Inlet Mixture"
        Mwm = sum(Mw*Inlet.z);

        "Calculate rho using a External Physical Properties Routine"
        rho = PP.LiquidDensity(Inlet.T,Inlet.P,Inlet.z);
        
        "Calculate Outlet Vapour Fraction"
        Outlet.v = PP.VapourFraction(Outlet.T, Outlet.P, Outlet.z);
        
        "Calculate Cp Using a External Physical Properties Routine"
        Cp = PP.LiquidCp(Inlet.T,Inlet.P,Inlet.z);
        
        "Pressure Ratio"
        Outlet.P = Inlet.P * Pratio;

        "Pressure Drop"
        Outlet.P  = Inlet.P - Pdrop;

        "Calculate Fluid Power"
        FPower * rho = -Pdrop * Inlet.F * Mwm;

        "Calculate Brake Power"
        BPower = FPower * Eff;
        
        "Calculate Eletric Power"
        EPower = BPower * Meff;
        
        "Calculate Outlet Temperature"
        (Outlet.T - Inlet.T) * rho * Cp = (Outlet.h - Inlet.h) * rho
        + Pdrop * Mwm * (1-Beta*Inlet.T);
        
        "Calculate Outlet Enthalpy"
        (Outlet.h - Inlet.h) * rho =  -Pdrop * Mwm;
        
        "Molar Balance"
        Outlet.F = Inlet.F;
        
        "Calculate Outlet Composition"
        Outlet.z = Inlet.z;

        "Calculate Head"
        Head = Outlet.h - Inlet.h;
end