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Numerical Diffusion in 4.0
Posted Nov 9, 2010, 7:14 p.m. EST 1 Reply
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Hi again,
I am still trying to transition to 4.0 and get things that worked in 3.5a running correctly in 4.0. One aspect is the old Navier Stokes module would allow me to manually tune the numeric diffusion parameters which is needed to get the correct solution behaviour for some natural convection problems.
I can't seem to find them in the new 4.0 interface, however after reviewing the help I see that crosswind diffusion, isotropic diffusion, etc are still listed as parameters for adjusting the simulation. Can someone provide a few GUI insights here? I feel like I missed something obvious ...
Thanks in advance.
I am still trying to transition to 4.0 and get things that worked in 3.5a running correctly in 4.0. One aspect is the old Navier Stokes module would allow me to manually tune the numeric diffusion parameters which is needed to get the correct solution behaviour for some natural convection problems.
I can't seem to find them in the new 4.0 interface, however after reviewing the help I see that crosswind diffusion, isotropic diffusion, etc are still listed as parameters for adjusting the simulation. Can someone provide a few GUI insights here? I feel like I missed something obvious ...
Thanks in advance.
1 Reply Last Post Nov 10, 2010, 5:19 a.m. EST
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Posted:
1 decade ago
Hi Heather,
If you select "Show More Options" from the Model Builder window's View menu (the downward pointing triangle at the top of the Model Builder window) you get access to some advanced settings and additional properties such as fluid-flow stabilization settings (numerical diffusion).
In the Settings window for the Laminar Flow node, for example, you find the streamline diffusion and crosswind diffusion in the Consistent Stabilization section. They are active by default, which is suitable for most fluid-flow models. In the Inconsistent Stabilization section you find the isotropic diffusion, which is turned off by default.
Best regards,
Magnus Ringh, COMSOL
If you select "Show More Options" from the Model Builder window's View menu (the downward pointing triangle at the top of the Model Builder window) you get access to some advanced settings and additional properties such as fluid-flow stabilization settings (numerical diffusion).
In the Settings window for the Laminar Flow node, for example, you find the streamline diffusion and crosswind diffusion in the Consistent Stabilization section. They are active by default, which is suitable for most fluid-flow models. In the Inconsistent Stabilization section you find the isotropic diffusion, which is turned off by default.
Best regards,
Magnus Ringh, COMSOL