Unable to Implement Equation using Kernel Objects

[Supernova963]

Hello,

For the attached CH equation I am struggling to implement the second term using any of the kernel objects. The first term looks like a standard diffusion equation, and I think the third can be implemented with ADMatBodyForce.

Any ideas on how to implement this term would be greatly appreciated, I've tried using MatDiffusion and FunctorElementalGradientAux but neither have sufficed.

Thank you.

[GiudGiud]

Hello

If we have that one it will be somewhere in mechanics or in the Phase Field-mechanics coupled inputs.

If not then you will need to develop it.

[Supernova963]

From looking at the solid mechanics module kernels it doesn't seem to be already built.

Before I try to develop it, is there any change I could make to a process I already tried. Currently I have the 11 and 22 components of the stress tensor saved to separate auxvariables, I then sum the two into a third auxvariable. My process stalled when I used the MatDiffusion kernel to try coupling the trace of stress with my concentration variable. Within the MatDiffusion kernel the diffusivity would a material object composed of everything before the divergence operator.