Apresenta

1
EQE038 Simulação e Otimização de Processos
Químicos
Aula 3 Advanced modeling capabilities in the
EMSO model editor.
Argimiro R. Secchi
EQ/UFRJ 29 de agosto de 2014
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Other features in the modeling language

• Plug-ins External Routines
• Termodynamics VRTherm
• EML Streams
• IF-THEN-ELSE
• Switching models (switcher)
• FOR

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Using External Routines - Plugins

• EMSO is a simulator based on equations and its
  modeling language allows to directly express the
  equation of the equipment.
• However, there are some cases that the
  description directly in the form of equations is
  not convenient, typical examples include
• Some parameters of the model require
  initialization procedures (routines)
• The mathematical relationships require a high
  number of data
• The user already has its own routine
  calculations
• EMSO solution plug-in system that allows any
  routine written in C, C or FORTRAN to be used
  within the models.
• The plug-in interface is open, anyone can
  implement a new plug-in.

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Using the Plugins
To use an external procedure in the models the
user needs to declare a special parameter called
Plugin
Once the Plugin has been declared, the user can
call its methods using the notation
Variable Plugin.method(args)

• Before running a simulation, EMSO will check
• If all methods used in the models were properly
  implemented in the plugin.
• If the number of arguments and the units of
  measure are correct.

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Using the Plugins

• Example
• Routine calculations developed by the user
  Plugin propterm.dll

Rankine cycle thermodynamic properties in
FORTRAN 90
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Using the Plugins
Applying in a thermoelectric power plant
File sample/water_steam/sample_power_plant.mso
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VRTherm Methods
Main Thermodynamic Models
Flash Calculation
Pure component Properties
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VRTherm Methods
Properties of mixtures
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Standard EML Streams
The development of a basic material stream is the
starting point for a library of models.In order
to made compatible with each other, the models
created ??by many different people need to be
directly connected.That is, it should be
possible the output calculated by a model be
connected to the input of another model.For
this goal to be reached, all models should use
standard streams, which enable integration of
different models featuring a library.
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Using EML Streams

• Inlet material streams should be of type stream
• Outlet material streams should be of type
• liquid_stream liquid phase
• vapour_stream vapor phase
• streamPH when the vaporized fraction of the
  stream is unknown. It made ??a flash calculation
  to determine the thermodynamic state of this
  stream.

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Example Flash Model
Models/flash.mso
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Flash Steady Simulation
Example run the flowsheet of the file
sample_flashPH.mso. The original problem is an
adiabatic flash. Consider also the results
specifying the pairs (T, P) and (T, Q) instead of
(P, Q). Test the problem of calculating the feed
temperature or feed pressure specifying T, P and
Q.
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Distributed Models Heat Exchanger
Models/HeatExchanger.mso
A heat exchanger may be represented by a system
formed by two ducts.
Description of the duct
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Heat Exchanger Duct Modeling
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Heat Exchanger Modeling
Aggregation in the heat exchanger
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Heat Exchanger Modeling
Using IF THEN ELSE END
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Heat Exchanger Distributed Model
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Heat Exchanger Distributed Model
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Heat Exchanger Simulation
Example run the flowsheets HeatX and
HeatX_Discretized in the file Sample_HeatExchanger
.mso. Compare the temperature of the output
stream. Export the results of the discrete to
Excel or LibreOffice building the temperature
profiles of the heat exchanger
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Switcher textual parameters
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Switcher textual parameters
Decisions independent of the user's choice
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Distributed Models pipe model
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Distributed Models pipe model
FOR command Vectors Matrices
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Exercise
1) Build a model of a pressure pan with a relief
valve (with constant equal to 0.07 cm2) which
opens when the pressure is greater than 5 times
atmospheric pressure, and closes when less than
four times this pressure. Consider a 5 L pan with
20 cm in diameter containing only water with an
initial level of 10 cm and a temperature of 25
C. The heating is done at a rate of 10 kW.
Simulate the pan for 10 minutes. Consider the
phases in thermodynamic equilibrium model and use
the Peng-Robinson model.
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Special thanks to
Prof. Rafael de Pelegrini Soares, D.Sc. Eng.
Gerson Balbueno Bicca, M.Sc. Eng. Euclides
Almeida Neto, D.Sc. Eng. Eduardo Moreira de
Lemos, D.Sc. Eng. Marco Antônio Müller
For helping in the preparation of this material
For supporting the ALSOC Project.
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EP 2013
... thank you for your attention!
http//www.enq.ufrgs.br/alsoc

• Process Modeling, Simulation and Control Lab
• Prof. Argimiro Resende Secchi, D.Sc.
• Phone [phone]
• E-mail arge_at_peq.coppe.ufrj.br
• http//www.peq.coppe.ufrj.br/Areas/Modelagem_e_sim
  ulacao.html