trixi-framework / trixi-framework/TrixiParticles.jl
Revise fluid CFL condition
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enhancement
- Dominant language
- Julia
- Stars
- 83
- Forks
- 24
- Avg merge
- 8d 18h
- Merged PRs (30d)
- 3
Description
Currently, we have implemented:
- Multiple different time step conditions, but only one of them is scaled by the CFL number. When using very stable time integration methods, this leads to situations where a larger time step would still be stable, but the
StepsizeCallbackdoesn't make it larger when the CFL number is increased. IMO, the CFL number should linearly scale all time step conditions. - Only static time step conditions. Nothing based on the current solution. We should investigate if that makes sense, i.e. if a simulation like a Taylor-Green vortex where the velocity tends to zero can increase the time step throughout the simulation.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by locating the StepsizeCallback and the existing time-step conditions in the repository. Read how the CFL number is applied and how current-solution state is available during a simulation. Done should include a decided approach for scaling all conditions and determining whether solution-dependent time steps are supported, with corresponding validation.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- julia
- Domain
- backend
- Issue type
- Feature
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 25/100