The energy equation add a source term

[czc-zju]

I want to add a source term to the energy equation to achieve ignition, can this be achieved?
This source term equation:
q=E/(r*t) ( t<tig)
q=0 ( t>tig)

[drummerdoc]

Personally, I'd make it a bit smoother than that, using a tanh function in t or something to keep things differentiable and well-behaved.... :)

[czc-zju]

Thank you！
In which file should I add this source item?

[baperry2]

The m_extSource member of the PeleLM class is a vector of (pointers to) multifabs that contains external source terms for all state variables across each level of refinement. The code contains the machinery to handle these terms but right now they are set to 0 everywhere. To add nonzero source terms, you'll have to write your own function that populates m_extSource with your desired source terms and use it instead of just setting the value to zero on initialization, when regridding, and when recomputing the external source at each timestep. I believe the following locations in the code should be sufficient:

$ grep -rn "m_extSource" | grep setVal
./PeleLMRegrid.cpp:358:   m_extSource[lev]->setVal(0.);
./PeleLMRegrid.cpp:460:   m_extSource[lev]->setVal(0.);
./PeleLMAdvance.cpp:72:     m_extSource[lev]->setVal(0.);
./PeleLMInit.cpp:106:   m_extSource[lev]->setVal(0.);

[baperry2]

Another quick note on this: in the low-Mach formulation, we transport enthalpy rather than internal energy. If I understand your intent properly, you will want to add a source term for the RHOH element of m_extSource and have all other elements be set to zero.

[czc-zju]

Thank you very much for your response！I am currently trying it out.
I want added a source term qig to the equation of h (enthalpy), which varies with time and is also dependent on spatial position. The purpose is as follows: