#*---------------------------------------------------------------------
* 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.
*
*----------------------------------------------------------------------
* Model of a tank basic
*----------------------------------------------------------------------
*
*   Description:
*       Generic model for a dynamic tank.
*
*   Assumptions:
*		* single- and two-phases involved
*       * dynamic
*
*----------------------------------------------------------------------
* Author: Rodolfo Rodrigues
* $Id$
*--------------------------------------------------------------------*#

using "streams";
using "vol_tank";


Model tank_basic
	ATTRIBUTES
	Brief 	= "Basic model for a dynamic tank";
	
	PARAMETERS
outer PP	as Plugin 	(Brief="External physical properties", Type="PP");
outer NComp as Integer 	(Brief="Number of components", Default=1);
	
	VARIABLES
in	Inlet 	as stream	(Brief="Inlet stream", PosX=0, PosY=0, Symbol="_{in}");
	Outletm	as stream	(Brief="Intermediary outlet stream", Symbol="_{outm}");
	Tank	as vol_tank	(Brief="Routine to volume tank calculation", Symbol="_{tank}");
	
	M(NComp)as mol		(Brief="Component molar holdup");
	Mt		as mol		(Brief="Total component molar holdup");
	E		as energy	(Brief="Internal energy");
	Q		as heat_rate(Brief="Reactor duty", Default=0);
	
	EQUATIONS
	"Component molar balance"
	diff(M) = Inlet.F*Inlet.z - Outletm.F*Outletm.z;
	
	"Component molar"
	M = Mt*Outletm.z;
	
	"Mole fraction normalisation"
	sum(Outletm.z) = 1;
	
	"Energy balance"
	diff(E) = Inlet.F*Inlet.h - Outletm.F*Outletm.h + Q;
end


#*---------------------------------------------------------------------
*	only vapour phase
*--------------------------------------------------------------------*#
Model tank_vap as tank_basic
	ATTRIBUTES
	Brief 	= "Model of a generic vapour-phase tank";
	
	EQUATIONS
	"Vapourisation fraction"
	Outletm.v = 1;

	"Vapour Enthalpy"
	Outletm.h = PP.VapourEnthalpy(Outletm.T,Outletm.P,Outletm.z);

	"Volume constraint"
	Tank.V = Mt*PP.VapourVolume(Outletm.T,Outletm.P,Outletm.z);

	"Total internal energy"
	E = Mt*Outletm.h;
end


#*---------------------------------------------------------------------
*	only liquid phase
*--------------------------------------------------------------------*#
Model tank_liq as tank_basic
	ATTRIBUTES
	Brief 	= "Model of a generic liquid-phase tank";
	
	EQUATIONS
	"Vapourisation fraction"
	Outletm.v = 0;

	"Liquid Enthalpy"
	Outletm.h = PP.LiquidEnthalpy(Outletm.T,Outletm.P,Outletm.z);
	
	"Volume constraint"
	Tank.V = Mt*PP.LiquidVolume(Outletm.T,Outletm.P,Outletm.z);
	
	"Total internal energy"
	E = Mt*Outletm.h - Outletm.P*Tank.V;
end


#*---------------------------------------------------------------------
*	liquid and vapour phases
*--------------------------------------------------------------------*#
Model tank_liqvap
	ATTRIBUTES
	Brief 	= "Model of a generic two-phase tank";
	
	PARAMETERS
outer PP		as Plugin(Brief="External physical properties", Type="PP");
outer NComp 	as Integer 	(Brief="Number of components", Default=1);

	VARIABLES
in	Inlet	 as stream			(Brief="Inlet stream", PosX=0, PosY=0, Symbol="_{in}");
	OutletmL as liquid_stream	(Brief="Intermediary liquid outlet stream", Symbol="_{outmL}");
out	OutletV  as vapour_stream 	(Brief="Outlet vapour stream", Symbol="_{outV}");
	Tank	 as vol_tank		(Brief="Routine to volume tank calculation", Symbol="_{tank}");
	
	M(NComp)as mol			(Brief="Component molar holdup");
	ML 		as mol 			(Brief="Molar liquid holdup");
	MV 		as mol 			(Brief="Molar vapour holdup");
	E		as energy		(Brief="Internal energy");
	Q		as heat_rate	(Brief="Reactor duty", Default=0);
	vL 		as volume_mol 	(Brief="Liquid Molar Volume");
	
	EQUATIONS
	"Component molar balance"
	diff(M) = Inlet.F*Inlet.z - (OutletmL.F*OutletmL.z + OutletV.F*OutletV.z);

	"Molar holdup"
	M = ML*OutletmL.z + MV*OutletV.z;
	
	
	"Mole fraction normalisation"
	sum(OutletmL.z) = 1;
	
	"Mole fraction normalisation"
	sum(OutletmL.z) = sum(OutletV.z);
	
	
	"Vapourisation fraction"
	OutletV.v = 1;
	
	"Vapourisation fraction"
	OutletmL.v = 0;
	
	
	"Energy balance"
	diff(E) = Inlet.F*Inlet.h - (OutletmL.F*OutletmL.h + OutletV.F*OutletV.h) + Q;
	
	"Total internal energy"
	E = ML*OutletmL.h + MV*OutletV.h;
	
	"Geometry constraint"
	Tank.V = ML*vL + MV*PP.VapourVolume(OutletV.T,OutletV.P,OutletV.z);
	
	
	"Chemical Equilibrium"
	PP.LiquidFugacityCoefficient(OutletmL.T,OutletmL.P,OutletmL.z)*OutletmL.z = 
		PP.VapourFugacityCoefficient(OutletV.T,OutletV.P,OutletV.z)*OutletV.z;
	
	"Mechanical Equilibrium"
	OutletmL.P = OutletV.P;
	
	"Thermal Equilibrium"
	OutletmL.T = OutletV.T;
	
	"Liquid Volume"
	vL = PP.LiquidVolume(OutletmL.T,OutletmL.P,OutletmL.z);
	
	"Tank Level"
	ML*vL = Tank.V;
end