source: branches/new_gui/my_folders/tenprobs/prob06.mso @ 898

#*---------------------------------------------------------------------
* 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.
*
*----------------------------------------------------------------------
* 6. Heat exchange in a series of tanks
*----------------------------------------------------------------------
*
*   Description:
*      This problem is part of a collection of 10 representative
*       problems in Chemical Engineering for solution by numerical methods
*       developed for Cutlip (1998).
*
*   Subject:
*       * Heat Transfer
*
*       Concepts utilized:
*               Unsteady-state energy balances, dynamic response of well mixed
*       heated tanks in series.
*
*       Numerical method:
*               * Simultaneous first order ODEs
*
*   Reference:
*               * CUTLIP et al. A collection of 10 numerical problems in 
*       chemical engineering solved by various mathematical software 
*       packages. Comp. Appl. in Eng. Education. v. 6, 169-180, 1998. 
*       * More informations and a detailed description of all problems
*       is available online in http://www.polymath-software.com/ASEE
* 
*----------------------------------------------------------------------
* Author: Rodolfo Rodrigues
* GIMSCOP/UFRGS - Group of Integration, Modeling, Simulation, 
*                                       Control, and Optimization of Processes
* $Id$
*--------------------------------------------------------------------*#
using "types";



#*---------------------------------------------------------------------
*       Model of a stream
*--------------------------------------------------------------------*#
Model oil_stream
        PARAMETERS
        W               as flow_mass    (Brief="Mass flow rate", DisplayUnit='kg/min');
        cp              as cp_mass              (Brief="Heat capacity of the oil", DisplayUnit='kJ/kg/K');
        
        VARIABLES
        T               as temperature;
        
        SET
        cp = 2*'kJ/kg/K';
        W = 100*'kg/min';
end

Model tank_source
        ATTRIBUTES
        Pallete = true;
        Brief   = "Simple inlet stream";
        Icon    = "icon/tank_source";
        
        VARIABLES
out Outlet      as oil_stream   (Brief="Outlet stream", PosX=1, PosY=0.5);
end

Model tank_sink
        ATTRIBUTES
        Pallete = true;
        Brief   = "Simple outlet stream";
        Icon    = "icon/tank_sink";
        
        VARIABLES
in      Inlet   as oil_stream   (Brief="Inlet stream", PosX=0, PosY=0.5);
end


Model heat_stream
        VARIABLES
        T               as temperature;
end

Model steam
        ATTRIBUTES
        Pallete = true;
        Brief   = "Simple inlet stream";
        Icon    = "icon/tank_source";
        
        VARIABLES
out Outlet      as heat_stream(Brief="Outlet stream", PosX=1, PosY=0.5);
end


#*---------------------------------------------------------------------
*       Model of one tank
*--------------------------------------------------------------------*#
Model heated_tank
        ATTRIBUTES
        Pallete = true;
        Brief   = "Simple model of a steady-state CSTR";
        Icon    = "icon/heated_tank";
        
        
        PARAMETERS
        UA              as Real                 (Brief="Product of the heat transfer coefficient and the area", Unit='kJ/min/K');
        
        
        VARIABLES
in      Inlet   as oil_stream   (Brief="Inlet stream", PosX=0.51, PosY=0);
out     Outlet  as oil_stream   (Brief="Outlet stream", PosX=1, PosY=0.975);
in      InletQ  as heat_stream  (Brief="Rate of heat supply", PosX=0, PosY=0.715);
        
        M               as mass                 (Brief="Mass in tank");
        Q               as heat_rate    (Brief="Rate of heat transferred", DisplayUnit='kJ/min');
        
        
        SET
        UA = 10*'kJ/min/K';
        
        
        EQUATIONS
        "Energy balance"
        (M*Outlet.cp)*diff(Outlet.T) = Inlet.W*Inlet.cp*(Inlet.T - Outlet.T) + Q;
        
        "Rate of heat transferred"
        Q = UA*(InletQ.T - Outlet.T);
end



#*---------------------------------------------------------------------
*       Three tanks in series
*--------------------------------------------------------------------*#
FlowSheet series_of_tanks
        VARIABLES
        feed    as oil_stream;
        
        
        DEVICES
        steam1  as steam;
        steam2  as steam;
        steam3  as steam;
        
        tank1   as heated_tank;
        tank2   as heated_tank;
        tank3   as heated_tank;
        
        
        CONNECTIONS
        feed             to tank1.Inlet;
        tank1.Outlet to tank2.Inlet;
        tank2.Outlet to tank3.Inlet;
        
        steam1.Outlet to tank1.InletQ;
        steam2.Outlet to tank2.InletQ;
        steam3.Outlet to tank3.InletQ;
        
        
        SPECIFY
        feed.T = (20 + 273.15)*'K';
        
        steam1.Outlet.T = (250 + 273.15)*'K';
        steam2.Outlet.T = (250 + 273.15)*'K';
        steam3.Outlet.T = (250 + 273.15)*'K';
        
        tank1.M = 1000*'kg';
        tank2.M = tank1.M;
        tank3.M = tank2.M;
        
        
        INITIAL 
        tank1.Outlet.T = (20 + 273.15)*'K';
        tank2.Outlet.T = tank1.Outlet.T;
        tank3.Outlet.T = tank2.Outlet.T;


        OPTIONS
#       Dynamic = false; # steady-state
        TimeStart = 0;
        TimeStep = 1;
        TimeEnd = 90;
        TimeUnit = 'min';
end