DriftDiffusionAction - where is CoeffDiffusion for Energy?

[ghost]

Hello, in my process of trying to utilize the DoNothingBCs to create an open boundary for species & energy to freely flow through, I noticed that in AddDriftDiffusionAction.C, lines 507 to 526 read:

if (energy)
  {
    InputParameters params3 = _factory.getValidParams("EFieldAdvection");
    params3.set<NonlinearVariableName>("variable") = {name};
    params3.set<std::vector<VariableName>>("potential") = {potential_name};
    params3.set<Real>("position_units") = getParam<Real>("position_units");
    params3.set<std::vector<SubdomainName>>("block") =
        getParam<std::vector<SubdomainName>>("block");
    _problem->addKernel("EFieldAdvection", name + "_advection", params3);

    InputParameters params4 = _factory.getValidParams("JouleHeating");
    params4.set<NonlinearVariableName>("variable") = {name};
    params4.set<std::vector<VariableName>>("potential") = {potential_name};
    params4.set<std::vector<VariableName>>("em") = {getParam<NonlinearVariableName>("electrons")};
    params4.set<std::string>("potential_units") = getParam<std::string>("potential_units");
    params4.set<Real>("position_units") = getParam<Real>("position_units");
    params4.set<std::vector<SubdomainName>>("block") =
        getParam<std::vector<SubdomainName>>("block");
    _problem->addKernel("JouleHeating", name + "_joule_heating", params4);
  }

These two kernels being included makes sense, but I'm wondering where CoeffDiffusion is for energy. In the Zapdos_Tutorial.pdf, equation 3.8 shows the individual kernels necessary for the electron energy density and lists "CoeffDiffusionEnergy" as one of them. Why is this absent?

Thanks!

[csdechant]

CoeffDiffusion is added for all species. Looking at line 490 to 526, it reads:

  if (charged)
  {
    InputParameters params1 = _factory.getValidParams("EFieldAdvection");
    params1.set<NonlinearVariableName>("variable") = {name};
    params1.set<std::vector<VariableName>>("potential") = {potential_name};
    params1.set<Real>("position_units") = getParam<Real>("position_units");
    params1.set<std::vector<SubdomainName>>("block") =
        getParam<std::vector<SubdomainName>>("block");
    _problem->addKernel("EFieldAdvection", name + "_advection", params1);
  }

  InputParameters params2 = _factory.getValidParams("CoeffDiffusion");
  params2.set<NonlinearVariableName>("variable") = {name};
  params2.set<Real>("position_units") = getParam<Real>("position_units");
  params2.set<std::vector<SubdomainName>>("block") = getParam<std::vector<SubdomainName>>("block");
  _problem->addKernel("CoeffDiffusion", name + "_diffusion", params2);

  if (energy)
  {
    InputParameters params3 = _factory.getValidParams("EFieldAdvection");
    params3.set<NonlinearVariableName>("variable") = {name};
    params3.set<std::vector<VariableName>>("potential") = {potential_name};
    params3.set<Real>("position_units") = getParam<Real>("position_units");
    params3.set<std::vector<SubdomainName>>("block") =
        getParam<std::vector<SubdomainName>>("block");
    _problem->addKernel("EFieldAdvection", name + "_advection", params3);

    InputParameters params4 = _factory.getValidParams("JouleHeating");
    params4.set<NonlinearVariableName>("variable") = {name};
    params4.set<std::vector<VariableName>>("potential") = {potential_name};
    params4.set<std::vector<VariableName>>("em") = {getParam<NonlinearVariableName>("electrons")};
    params4.set<std::string>("potential_units") = getParam<std::string>("potential_units");
    params4.set<Real>("position_units") = getParam<Real>("position_units");
    params4.set<std::vector<SubdomainName>>("block") =
        getParam<std::vector<SubdomainName>>("block");
    _problem->addKernel("JouleHeating", name + "_joule_heating", params4);
  }

So if a variable species is charged, then "EFieldAdvection" is added, but if the variable species is the mean energy density, then both "EFieldAdvection" and "JouleHeating" is added. The name "CoeffDiffusionEnergy" was before AD functionality was added to MOOSE and Jacobians had to been hard coded, resulting in a separate Diffusion Kernel for electrons, mean energy, and other species. Hope that clears things up.

[ghost]

I see! So instead of using a separate energy density diffusion and advection kernel, the ADGasElectronMoments couples electron flux to the energy flux?