Sorry, first pull request, please point out where documentation should go.
For some applications (immersed boundary methods, sponge regions, generation of FST etc) it is common to have a forcing term that is linearly proportional to the velocity, we denote this as f = \chi * u, where \chi is a scalar field.
Imposing this in user_f results in an explicit formulation where f = \chi * u^(n) that can lead to stability issues for large \chi.
Here we impose an implicit formulation f = \chi * u^(n+1)
Predicted problems:
I'm 99% sure if \chi is defined on the boundary, we'll have to adjust the pressure boundary conditions.
Nothing has been tested on GPU's etc yet
not a lot of testing has gone into this, I'm only pull requesting so that it can be discussed
Sorry, first pull request, please point out where documentation should go.
For some applications (immersed boundary methods, sponge regions, generation of FST etc) it is common to have a forcing term that is linearly proportional to the velocity, we denote this as f = \chi * u, where \chi is a scalar field.
Imposing this in user_f results in an explicit formulation where f = \chi * u^(n) that can lead to stability issues for large \chi.
Here we impose an implicit formulation f = \chi * u^(n+1)
Predicted problems: