#*-------------------------------------------------------------------
* EMSO Model Library (EML) Copyright (C) 2004 - 2008 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 - 2008 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.
*
*--------------------------------------------------------------------
* Flash separator sample file.
*--------------------------------------------------------------------
*
* This sample file needs VRTherm (www.vrtech.com.br) to run.
*
*--------------------------------------------------------------------
* Author: Rafael de Pelegrini Soares
* $Id: Sample_flash_pid.mso 941 2011-07-15 18:44:52Z mamuller $
*------------------------------------------------------------------*#

using "stage_separators/flash";
using "pressure_changers/valve.mso";
using "controllers/PIDIncr";

FlowSheet Flash_Dynamic
	
	PARAMETERS
	PP	as Plugin(Brief="Physical Properties",Type="PP",
		Components = ["n-butane", "benzene", "n-octane"],
		LiquidModel = "PR",
		VapourModel = "PR");
	NComp	as Integer;

	VARIABLES
	Q	as energy_source (Brief="Heat supplied");
	
	DEVICES
	pidL as PIDIncr; #Level controller
	pidP as PIDIncr; #Pressure controller
	fl as flash;
	s1 as source;
	valve_top as valve_flow;
	valve_bot as valve_flow;

	SET
	NComp = PP.NumberOfComponents;
	
	pidL.PID_Select = "Parallel_AWBT";
	pidP.PID_Select = "Parallel_AWBT";
	
	#Flash model parameters
	fl.Lenght = 10 * 'm';
	fl.Diameter = 1 * 'm';
	fl.Orientation = "vertical";
	
	#Maximum and minimum values
	pidP.MaxInput=2.36;
	pidP.MinInput=0;
	pidL.MaxInput=2;
	pidL.MinInput=0;
	valve_top.MaxFlow=300*'kmol/h';
	valve_top.MinFlow=0*'kmol/h';
	valve_bot.MaxFlow=692.7*'kmol/h';
	valve_bot.MinFlow=0*'kmol/h';

	CONNECTIONS
	s1.Outlet to fl.Inlet;
	Q.OutletQ to fl.InletQ;
	fl.OutletLiquid to valve_bot.Inlet;
	fl.OutletVapour to valve_top.Inlet;
	fl.LI to pidL.Input;
	fl.PI to pidP.Input;
	pidP.Output to valve_top.FlowFraction;
	pidL.Output to valve_bot.FlowFraction;

	SET
	#Level controller configuration
	pidL.bias=0.5;
	pidL.gain=1.1776;
	pidL.derivTime=19*'s';
	pidL.intTime=76*'s';
	pidL.tau=1*'s';
	pidL.tauSet=1*'s';
	pidL.alpha =1;
	pidL.beta =1;
    pidL.gamma =1;
	pidL.Mode = "Automatic";
	pidL.Clip = "Clipped";
	pidL.Action = "Direct";
	
	#Pressure controller parameters
	pidP.bias=0.5;	
	pidP.gain=0.9275;
	pidP.derivTime=18*'s';
	pidP.intTime=72*'s';
	pidP.tau=1*'s';
	pidP.tauSet=1*'s';
	pidP.alpha =1;
	pidP.beta =1;
	pidP.gamma =1;
	pidP.Mode = "Automatic";		
	pidP.Clip = "Clipped";
	pidP.Action = "Direct";

	#Initial conditions
	fl.Levelpercent_Initial = 0.5;
	fl.Temperature_Initial = 340 * 'K';
	fl.Composition_Initial = [0.1, 0.1, 0.8];

	SPECIFY

	Q.OutletQ = 1026.32 * 'kJ/s';

	#Level controller parameters
	pidL.SetPoint=0.5;

	EQUATIONS
	#Feed stream
	s1.Composition = [0.3, 0.3, 0.4];	
	s1.P = 5 * 'atm';	
	
	#Disturbance
	if time < 0.5*'h' then
		s1.T = 338 * 'K';
		s1.F = 496.3 * 'kmol/h';
	else
		s1.T = 360 * 'K';
		s1.F = 450 * 'kmol/h';
	end
	
	#Setpoint change
	if time < 2*'h' then
		pidP.SetPoint=1;
	else
		pidP.SetPoint=2;
	end	
	
	OPTIONS
	TimeStep = 0.02;
	TimeEnd = 3;
	TimeUnit = 'h';
	DAESolver(File="dassl");
end