code_saturne User's Forum

Hello,

Boundary conditions in code_saturne may use coupled components for multi-dimensional fields, which is not the case for neptune_cfd. For scalars, coefficients should be similar.

I am out of office today (without my work computer) so cannot check the neptune_cfd code right away (and the rest ...

Hello,

Thanks for the feedback for the linear solver tolerance. This is a tricky subject, because the tolerance used is strongly related to the right-hand side normalization choice, and this has changed several tiles across code_saturne versions to try to have the "best" possible logic (i.e. be ...

Hello,

1) I am not sure how this is computed. I will check, but will probably not be able to look at this in detail before 10 days or so.

2) Without this parameter, I assume the risk is to have very strong variations in some matrix coefficients, but I am not sure we ever tested the feature without ...

Hello,

I would be surprised if we did not use a consistent momentum interpolation, though I am not an expert in that part of the code.

For 1), yes, the Fourier number may be involved in the time step computation for the fluid region. This may cause issues in some cases where turbulent models lead ...

Hello,

This topic should be in "general usage", as it contains questions relative to code usage, and not discussions on development, roadmap, .... exxcept for the question about neptune_cfd.

AS for the question, neptune_cfd is provided to some industrial or academic partners, and this is subject ...

Hello,

In v9.0, ischtp corresponds to 'cs_glob_time_step->time_order' in C (and is still called ischtp in Fortran).

It is set in cs_setup.cpp, near line 1090.

Best regards,

Yvan

Hello,

1) I did not check the exact formulas used (the code is in cs_time_step_compute.cpp, but also has additional layers in cs_matrix_time_step calls), but by default, there is indeed both a Courant and Fourier limitation. In the solid zone, the CFL should be zero, so only the Fourier part is ...

Hello,

Ok thanks, this will be in the next update of Syrthes (probably in a few weeks).

Best regards,

Yvan

Hello,

There is currently no external GitHub of Gitlab mirror for Syrthes, and the support address may not be checked as regularly as that for code_saturne (development resources on Syrthes are currently quite limited, but some members of the code_saturne dev team have write access to the internal ...

Hello,

For polyhedral meshes, our feedback is still limited, but your options seem reasonable.

Independently of the mesh type, small time steps usually lead to faster linear solver convergence, so for such cases, gradients and balances (whose cost is independent of the time step) can become ...