4. Brief Introduction to Inputs

The dictionary CanteraTorchProperties is the original dictionary of DeepFlame. It reads in network related parameters and configurations. It typically looks like:

chemistry           on;
CanteraMechanismFile "ES80_H2-7-16.yaml";
transportModel "Mix";
odeCoeffs
{
    "relTol"   1e-15;
    "absTol"   1e-24;
}
inertSpecie        "N2";
zeroDReactor
{
    constantProperty "pressure";
}

splittingStretagy false;

TorchSettings
{
    torch on;
    GPU   off;
    log  on;
    torchModel "HE04_Hydrogen_ESH2_GMS_sub_20221101";
    coresPerNode 4;

}
loadbalancing
{
        active  false;
        //log   true;
}

In the above example, the meanings of the parameters are:

• CanteraMechanismFile: the name of the reaction mechanism file.

• transportModel: the default model is Mix, but other models including UnityLewis and Multi are also availabile.

• constantProperty: property set to be constant during reaction. It can be set to pressure or volume.

• odeCoeffs: the ode tolerance. 1e-15 and 1e-24 are used for network training, so they should be kept the same when comparing results with and without DNN. Default values are 1e-9 and 1e-15.

• TorchSettings: all paramenters regarding the usage of DNN. This section will not be read in CVODE cases.

• torch: the switch used to control the on and off of DNN. If users are running CVODE, this needs to be switched off.

• GPU: the switch used to control whether GPU or CPU is used to carry out inference.

• torchModel: name of network.

• coresPerNode: If you are using one node on a cluster or using your own PC, set this parameter to the actual number of cores used to run the task. If you are using more than one node on a cluster, set this parameter the total number of cores on one node. The number of GPUs used is auto-detected.

The dictionary combustionProperties is the original dictionary of DeepFlame. It reads in network related parameters and configurations. It typically looks like:

combustionModel  flareFGM;//PaSR,EDC

EDCCoeffs
{
    version v2005;
}

PaSRCoeffs
{
   mixingScale
   {
      type   globalScale;//globalScale,kolmogorovScale,geometriMeanScale,dynamicScale
      globalScaleCoeffs
      {
        Cmix  0.01;
      }

      dynamicScaleCoeffs
      {
        ChiType      algebraic;// algebraic; transport;
      }
    }
   chemistryScale
   {
      type  globalConvertion;//formationRate,globalConvertion
      globalConvertionCoeffs
      {
           fuel CH4;
           oxidizer O2;
      }
   }

}

flareFGMCoeffs
{
  buffer           false;
  scaledPV         false;
  combustion       false;
  ignition         false;
  solveEnthalpy    false;
  flameletT        false;
  relaxation       false;
  DpDt             false;
/*ignition         false;
  ignBeginTime     0.1;
  ignDurationTime  0.0;
  x0               0.0;
  y0               0.0;
  z0               0.0;
  R0               0.0;*/
  Sct              0.7;
  bufferTime       0.0;
  speciesName      ("CO");
}

In the above example, the meanings of the parameters are:

• combustionModel: the name of the combustion model, alternative models include PaSR, EDC, flareFGM.

• EDCCoeffs, PaSRCoeffs, flareFGMCoeffs: model cofficients we need to define.

• mixingScale: turbulent mixing time scale including globalScale,kolmogorovScale,geometriMeanScale,dynamicScale.

• ChiType: algebraic and transport are available for ChiType when selecting dynamicScale.

• chemistryScale: chemistry reaction time scale including formationRate,globalConvertion .

• buffer: switch for buffer time.

• scaledPV:the switch is used to determine whether to use scaled progress variables or not.

• combustion:the switch is used to control whether the chemical reactions are on or off.

• ignition:the switch is used to control whether the ignition is on or off.

• solveEnthalpy:the switch is used to determine whether to solve enthalpy equation or not.

• flameletT:the switch is used to determine whether to read flame temperature from table or not.

• relaxation:the switch is used to determine whether to use relaxation iteration for transport equations or not.

• DpDt:the switch is used to determine whether to include material derivatives or not.

• ignBeginTime:beginning time of ignition.

• ignDurationTime:duration time of ignition.

• x0, y0, z0:coordinate of ignition center.

• R0:radius of ignition region.

• Sct:turbulent Schmidt number, default value is set as 0.7.

• speciesName:name of species we need to lookup.