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Initialize Block

This block contains information about reaction, spark igition and reduced manifold chemistry calculation (e.g FPI, ANN) This block contains information about reaction, spark igition and reduced manifold chemistry calculation (e.g FPI, ANN)

Warning

This block is mandatory for all simulations.

Flags Overview

Note

All flags and their description are included in the table below. A detailed description of which values are possible for each input flag follows.

Flag Required Description
REACTIVE Yes determine whether to activiate reaction for the flow
REACTION_START_IT Yes determine from which iteration step reaction is activated
PHYSCHEM_LIB Yes determine which module is used to calculate chemical reaction
TEMPER_TH No determine the lower limit for the maximum temperature at which the reaction is computed, works as numerical catalyst
USE_FPI No determine whether FPI is used for the chemistry computation
READ_BINARY Yes determine whether the FPI table is ASCII data format or binary data format
FORCING Yes determine whether to force the sum of all species mass fractions to be 1
Y_FORCING_TYPE Yes determine how to enforce the sum of mass fractions to be 1
ADD_SPARK No specify whether an ignition spark is added to trigger the combustion process
SPARK_XCENTER No specify the \(x\)-coordinate of the spark center location
SPARK_YCENTER No specify the \(y\)-coordinate of the spark center location
SPARK_ZCENTER No specify the \(z\)-coordinate of the spark center location
REDUCED_KINETIC No specify whether to use a reduced chemical kinetic mechanism based on the QSS (quasi-steady-state) approximation
USE_ANN No determine whether to use the ANN for chemical source term calculation
USE_ANN_FPI No determine whether to use the ANN model for the chemistry tabulation
USE_EOS_TABLE No specify whether to use a tabulated equation of state (EOS) instead of an analytical EOS
USE_ANN_MOE No specify whether to use a MOE (mixture-of-experts) neural network model

Flags Details

REACTIVE

Turn on/off the reaction.

  • Type: Boolean
  • Values: True or False.
  • Default: False

REACTION_START_IT

Iteration step from which reaction is turned on.

  • Type: Integer
  • Values: Whatever suits your simultion.
  • Default: 1

PHYSCHEM_LIB

Model number for chemistry calculation

  • Type: Integer
  • Values: 1 (using Cantera).
  • Default: 1

TEMPER_TH

Temperature from which reaction is computed.

  • Type: Real (K)
  • Values: Whatever suits your simulation.
  • Default: 0.D0

USE_FPI

Turn on/off tabulation method for chemistry calculation.

  • Type: Boolean
  • Values: True or False.
  • Default: False

READ_BINARY

Use binary data format in FPI table or not.

  • Type: Boolean
  • Values: True or False.
  • Default: False

FORCING

Force the total mass fractions to be 1 or not.

  • Type: Boolean
  • Values: True or False.
  • Default: True

Y_FORCING_TYPE

Model choice to enforce the mass fractions to be 1.

  • Type: Integer
  • Values: 0 (normalizing all species mass fractions) or 1 (computing all species mass fractions except 1 inert species and the mass fraction of this inert species makes the total mass fractions to be 1).
  • Default: 0

ADD_SPARK

Turn on/off the ignition spark source to initiate combustion

  • Type: Boolean
  • Values: True or False.
  • Default: False

SPARK_XCENTER

Define the \(x\)-direction coordinate of the ignition spark center

  • Type: REAL
  • Default: 0.0

SPARK_YCENTER

Define the \(y\)-direction coordinate of the ignition spark center

  • Type: REAL
  • Default: 0.0

SPARK_ZCENTER

Define the \(z\)-direction coordinate of the ignition spark center

  • Type: REAL
  • Default: 0.0

REDUCED_KINETIC

Enable or disable the use of a QSS-based reduced chemical kinetic mechanism. Making sure -DENABLE_QSS=ON in the run_cmake_script.sh file.

  • Type: Boolean
  • Values: True or False.
  • Default: False

USE_ANN

Turn on/off the ANN model for chemical source term calculation.

  • Type: Boolean
  • Values: True or False.
  • Default: False

USE_ANN_FPI

Turn on/off the ANN model for chemistry tabulation.

  • Type: Boolean
  • Values: True or False.
  • Default: False

USE_EOS_TABLE

Enable or disable the use of a pre-tabulated equation of state (EOS) for thermodynamic property evaluation

  • Type: Boolean
  • Values: True or False.
  • Default: False

USE_ANN_MOE

Enable or disable the use of a MOE-based neural network model for evaluating chemical source terms instead of Cantera

  • Type: Boolean
  • Values: True or False.
  • Default: False

Example:

&nml_reaction
   REACTIVE = .true.,
   REACTION_START_IT = 1,
   PHYSCHEM_LIB = 1,
   TEMPER_TH = 0.D0,
   USE_FPI = .false.,
   READ_BINARY = .false.,
   FORCING = .true.,
   Y_FORCING_TYPE = 0,
   ADD_SPARK = .FALSE.,
   SPARK_XCENTER = 0.02d0,
   SPARK_YCENTER = 0.035d0,
   SPARK_ZCENTER = 0.0025d0 
   USE_ANN = .false.,
   USE_ANN_FPI = .false.
   REDUCED_KINETIC=.false.,
   USE_EOS_TABLE=.False.,
   USE_ANN_MOE = .false.
/