#*-------------------------------------------------------------------
* 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: Maurício Carvalho Maciel
* $Id: batch_dist.mso 735 2009-02-27 02:00:39Z bicca $
*--------------------------------------------------------------------*#
using "streams";
	
Model Diff_Dist
	ATTRIBUTES
	Pallete 	= true;
	Icon 		= "icon/BatchDist"; 
	Brief 		= "Model of a Batch Differential Distillation.";
	Info 		=
"== Assumptions ==
* perfect mixing of both phases;
* thermodynamics equilibrium;
* no liquid entrainment in the vapour stream.
	
== Specify ==
* the inlet stream;
* the liquid inlet stream;
* the molar flow of the vapour outlet stream.
	
== Initial Conditions ==
* the distillator temperature (T);
* the distillator liquid level (Level);
* (NoComps - 1) compositions in the distillator or in the OutletV.
";

	PARAMETERS
outer PP 		as Plugin	(Brief = "External Physical Properties", Type="PP");
outer NComp 	as Integer	(Brief = "Number of chemical components", Lower = 1);
	Across 		as area 	(Brief = "Cross Section Area");
	V 			as volume 	(Brief = "Total volume");
	
	VARIABLES
in	Inlet	as stream (Brief="Feed stream", PosX=0, PosY=0.9385, Symbol="_{in}");
in	InletLiquid 	as stream (Brief="Liquid inlet stream", PosX=0.5, PosY=0.1984, Symbol="_{inL}"); # FIXME
out	OutletVapour as vapour_stream (Brief="Vapour outlet stream", PosX=1, PosY=0.1984, Symbol="_{outV}");
in	InletQ 	as power (Brief="Heat supplied", PosX=1, PosY=0.9578, Symbol="_{in}");

	M(NComp) 	as mol 			(Brief="Molar Holdup in the distillator");
	ML 			as mol 			(Brief="Molar liquid holdup");
	MV 			as mol 			(Brief="Molar vapour holdup");
	E 			as energy 		(Brief="Total Energy holdup on distillator");
	volL 		as volume_mol 	(Brief="Liquid Molar Volume");
	volV 		as volume_mol 	(Brief="Vapour Molar volume");
	Level		as length 		(Brief="Level of liquid phase", Default=1, Lower=0);
	T 			as temperature	(Brief="Temperature on distillator");
	P 			as pressure		(Brief="Pressure on distillator");
	x(NComp)	as fraction 	(Brief = "Molar Fraction of the Liquid of the distillator");
	h 			as enth_mol		(Brief="Molar Enthalpy of the liquid of the distillator");
	
	EQUATIONS
	
	"Component Molar Balance"
	diff(M)= Inlet.F*Inlet.z + InletLiquid.F*InletLiquid.z - OutletVapour.F*OutletVapour.z;
	
	"Energy Balance"
	diff(E) = Inlet.F*Inlet.h + InletLiquid.F*InletLiquid.h - OutletVapour.F*OutletVapour.h + InletQ;
	
	"Molar Holdup"
	M = ML*x + MV*OutletVapour.z; 
	
	"Energy Holdup"
	E = ML*h + MV*OutletVapour.h - P*V;
	
	"Mol fraction normalisation"
	sum(x)=1.0;
	sum(x)=sum(OutletVapour.z);

	"Liquid Volume"
	volL = PP.LiquidVolume(T, P, x);
	
	"Vapour Volume"
	volV = PP.VapourVolume(OutletVapour.T, OutletVapour.P, OutletVapour.z);
	
	"Chemical Equilibrium"
	PP.LiquidFugacityCoefficient(T, P, x)*x = 
		PP.VapourFugacityCoefficient(OutletVapour.T, OutletVapour.P, OutletVapour.z)*OutletVapour.z;

	"Mechanical Equilibrium"
	P = OutletVapour.P;
	
	"Thermal Equilibrium"
	T = OutletVapour.T;
	
	"Geometry Constraint"
	V = ML*volL + MV*volV;
	
	"Level of liquid phase"
	Level = ML*volL/Across;
	
	"Enthalpy"
	h = PP.LiquidEnthalpy(T, P, x);
	
end