mdolab / mdolab/adflow

Unsteady timestep doesn't stop after l2Convergence is reached

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bug
Dominant language
Fortran
Stars
332
Forks
124
PR merge metrics
No merged PRs in 30d

Description

Type of issue

What types of issue is it?

  • Bug (probably?)

Description

In an unsteady RANS simulation, the solver doesn't stop when the l2Convergence is reached for a given timestep.

Steps to reproduce issue

Run the attached files.

Current behavior

The following behavior only happens after the first time step. The first time step works fine.

If the RK or DADI solver is used, the solver runs until nCycles is reached.
If the ANK solver is used, the CLF number goes to 0 after l2Convergence is approximatly reached. Even though there is an ankcflmin of 1.0.
The NK solver just stops making progress after l2Convergence is approximatly reached.

Expected behavior

Once l2Convergence is reached, the solver should stop executing the current timestep and start the next one.

Code version (if relevant)

adflow 2.2

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the attached unsteady.zip reproduction files and trace timestep convergence handling after the first timestep for the RK, DADI, ANK, and NK solvers. Compare the stopping behavior with l2Convergence and nCycles, then verify that each solver advances to the next timestep once convergence is reached.

Written by the indexing model from the issue text.

Assessment

Tech stack
fortran
Domain
hpc
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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