Menu

Discussion Forum

New Discussion
Filter

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

storing one variable only

Posted Oct 17, 2018, 6:12 a.m. EDT Fluid & Heat, Computational Fluid Dynamics (CFD), Heat Transfer Version 5.3a 4 Replies

Asal Bidarmaghz
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear all, I have a model with 3 variables of T, P and v. what is the best way of only storing T in solutions to save on size? do I need to do it via batch mode? I dont have COMSOL with matlab so probably matlab is not an option.

many thanks, Regards, Asal

4 Replies Last Post Nov 8, 2018, 11:22 a.m. EST
Magnus Ringh COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 6 years ago Oct 17, 2018, 8:27 a.m. EDT
Updated: 6 years ago Oct 17, 2018, 8:30 a.m. EDT

Hi Asal,

Yes, you can do it by clearing the Store in output check box in the Field nodes for the dependent variables that you do not want to store. The Field nodes appear under Solver Configurations>Solution>Dependent Variables (you may need to right-click the Study node and choose Show Default Solver to see the solver configuration nodes). Also see the following blog post:

https://www.comsol.com/blogs/minimize-your-model-file-size-with-storing-solution-techniques/

Best regards, Magnus Ringh, COMSOL

Hi Asal, Yes, you can do it by clearing the **Store in output** check box in the **Field** nodes for the dependent variables that you do not want to store. The **Field** nodes appear under **Solver Configurations>Solution>Dependent Variables** (you may need to right-click the **Study** node and choose **Show Default Solver** to see the solver configuration nodes). Also see the following blog post: Best regards, Magnus Ringh, COMSOL
Asal Bidarmaghz
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 6 years ago Nov 8, 2018, 4:28 a.m. EST

Dear Magnus,

thank you. As I am doing one way coupling of T and (V,P) so that I solve the model for V and P then use these results to solve for T, then unchecking the variables of V and P in the store solution looks like there is not fluid flow modelled and is pure conduction. Is there any other way?

Regards, Asal

Dear Magnus, thank you. As I am doing one way coupling of T and (V,P) so that I solve the model for V and P then use these results to solve for T, then unchecking the variables of V and P in the store solution looks like there is not fluid flow modelled and is pure conduction. Is there any other way? Regards, Asal
Jeff Hiller COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 6 years ago Nov 8, 2018, 11:16 a.m. EST

Hello Asal,

What variables you choose to store in the output does not affect the equations that are solved. In particular, not storing the velocity vector will not make it a pure conduction problem.

So if the solution of your model appears to reflect pure conduction, it is likely that you did not specify the velocity field correctly for the convective term (That's happened to me a couple of times:) ), or that the convective effects in this particular problem are so small that their impact on the solution are drowned out by the conduction.

Best,

Jeff

-------------------
Jeff Hiller
Hello Asal, What variables you choose to store in the output does not affect the equations that are solved. In particular, not storing the velocity vector will not make it a pure conduction problem. So if the solution of your model appears to reflect pure conduction, it is likely that you did not specify the velocity field correctly for the convective term (That's happened to me a couple of times:) ), or that the convective effects in this particular problem are so small that their impact on the solution are drowned out by the conduction. Best, Jeff
Asal Bidarmaghz
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 6 years ago Nov 8, 2018, 11:22 a.m. EST

Dear Jeff, Many thanks. So I attached my initial values set up for second sub-study (T). what you are saying is that even with this arrangement, I can still uncheck the v,p in the store solutions?

Regards, Asal

Dear Jeff, Many thanks. So I attached my initial values set up for second sub-study (T). what you are saying is that even with this arrangement, I can still uncheck the v,p in the store solutions? Regards, Asal

Attachments:

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content