source: mso/sample/stage_separators/sample_batch_dist_PID.mso @ 100

#*-------------------------------------------------------------------
* 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.
*
*--------------------------------------------------------------------
* Sample file for batch distillation with controllers
*--------------------------------------------------------------------
* 
* This sample file needs VRTherm DEMO (www.vrtech.com.br) to run.
*
*----------------------------------------------------------------------
* Author: 
* $Id: sample_batch_dist_PID.mso 86 2006-12-08 20:58:15Z paula $
*--------------------------------------------------------------------*#
using "stage_separators/batch_dist";
using "controllers/PIDs";

FlowSheet TesteBatch_PID
        
        PARAMETERS
        PP      as CalcObject(Brief="Physical Properties",File="vrpp");
        NComp   as Integer;
        P_max   as pressure(Brief="Maximum Pressure on distillator");
        P_min   as pressure(Brief="Minimum Pressure on distillator");
        
        VARIABLES
        P_ad    as fraction(Brief="Dimensionless pressure");
        P_set   as pressure(Brief="Minimum Pressure on distillator");

        SET
        PP.Components = [ "isobutane", "benzene" ];
        PP.LiquidModel = "PR";
        PP.VapourModel = "PR";
        NComp = PP.NumberOfComponents;
        
        DEVICES
        batch   as Diff_Dist;
        reflux  as stream_therm;
        feed    as stream_therm;
        pidP    as PID_Ideal_AWBT;
        
        CONNECTIONS
        reflux to batch.InletL;
        feed to batch.Inlet;

        EQUATIONS
        if batch.Level > 1E-3 then
                batch.Q = 3.7743e6 * "kJ/h";
        else
                batch.Q = 0 * "kJ/h";
        end

    "Pressure Controller"
        pidP.Parameters.tau = 0*"s";    
        pidP.Parameters.tauSet = 0*"s"; 
        pidP.Parameters.alpha = 0.3;
        pidP.Parameters.bias = 0;       
        pidP.Parameters.gamma = 1;
        pidP.Parameters.beta = 1;
        pidP.Options.action = -1;
        pidP.Options.clip = 1;
        pidP.Options.autoMan = 0;
        pidP.Parameters.intTime = 0.1*"min";
        pidP.Parameters.gain = 1;
        pidP.Parameters.derivTime = 0.02*"min";
        pidP.Ports.setPoint = (P_set-P_min)/(P_max-P_min);
        pidP.Ports.input = P_ad;
        P_ad = (batch.P-P_min)/(P_max-P_min);
        batch.OutletV.F = 500 * "kmol/h" * pidP.Ports.output;

        SPECIFY
        reflux.F = 0 * "kmol/h";
        reflux.T = 328 * "K";
        reflux.P = 180 * "kPa";
        reflux.z = [0.5, 0.5];
        reflux.v = 0;
        
        feed.F = 0 * "kmol/h";
        feed.T = 328 * "K";
        feed.P = 180 * "kPa";
        feed.z = [0.5, 0.5];
        feed.v = 0;

        P_set = 300 * "kPa";

        SET
        batch.V = 3 * "m^3";
        batch.Across = 1 * "m^2";
        P_max = 500 * "kPa";
        P_min = 100 * "kPa";
        
        INITIAL
        batch.T = 298 *"K";
        batch.Level = 2.5 * "m";
        batch.x(2) = 0.2;
        
        OPTIONS
        relativeAccuracy = 1e-5;
        
        time = [0:0.01:6]*"min";
end