Hello,
Sorry, I did not have the time to test the case yet. I'll let you know as soon as I run it.
Best regards,
Yvan
Divergence for simple geometry room
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Re: Divergence for simple geometry room
Hello,
Ok, Thanks.
Even in steady simulation, divergence problem happned.
Best regards,
Hamada
Ok, Thanks.
Even in steady simulation, divergence problem happned.
Best regards,
Hamada
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- Posts: 4085
- Joined: Mon Feb 20, 2012 3:25 pm
Re: Divergence for simple geometry room
Hello,
Changing the outlet to "imposed pressure outlet" alone was not sufficient, but switching to least-squares gradient reconstruction with full extended neighborhood, I can run 500 iterations just fine (tested with v7.0).
Best regards,
Yvan
Changing the outlet to "imposed pressure outlet" alone was not sufficient, but switching to least-squares gradient reconstruction with full extended neighborhood, I can run 500 iterations just fine (tested with v7.0).
Best regards,
Yvan
Re: Divergence for simple geometry room
Hello,
Thank you for the test.
I am grad to hear that steady simulation can be done by steady simulation.
Also how about unsteady case?
Do you think it can be done with Ver.6?
Finally I want to do pressure-driven flow by SRC code, but now the simulation has a divergenec problem with Ver.6.
Best regards,
Tsubasa
Thank you for the test.
I am grad to hear that steady simulation can be done by steady simulation.
Also how about unsteady case?
Do you think it can be done with Ver.6?
Finally I want to do pressure-driven flow by SRC code, but now the simulation has a divergenec problem with Ver.6.
Best regards,
Tsubasa
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- Posts: 4085
- Joined: Mon Feb 20, 2012 3:25 pm
Re: Divergence for simple geometry room
Hello,
I actually ran the test for an unsteady flow (as your setup.xml was set for unsteady, constant time step).
This should probably also work in v6.0, though I recommend upgrading to v7.0.
Pressure driven flow should work, but may be a bit more sensitive. Increasing the pressure difference progressively (using a ramp type function) rather than all at once might help.
Best regards,
Yvan
I actually ran the test for an unsteady flow (as your setup.xml was set for unsteady, constant time step).
This should probably also work in v6.0, though I recommend upgrading to v7.0.
Pressure driven flow should work, but may be a bit more sensitive. Increasing the pressure difference progressively (using a ramp type function) rather than all at once might help.
Best regards,
Yvan
Re: Divergence for simple geometry room
Hello,
Thanks a lot.
At first, I will build Ver.7 and do the test with it.
Best regards,
Tsubasa
Thanks a lot.
At first, I will build Ver.7 and do the test with it.
Best regards,
Tsubasa
Re: Divergence for simple geometry room
Hello Yvan,
In the previou post, you said "least-squares gradient reconstruction with full extended neighborhood".
Is this same to "least squares method over extended cell neighborhood" in Ver.6?
Best regards,
Tsubasa
In the previou post, you said "least-squares gradient reconstruction with full extended neighborhood".
Is this same to "least squares method over extended cell neighborhood" in Ver.6?
Best regards,
Tsubasa
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- Posts: 4085
- Joined: Mon Feb 20, 2012 3:25 pm
Re: Divergence for simple geometry room
Hello,
Yes, it is the same.
Best regards,
Yvan
Yes, it is the same.
Best regards,
Yvan
Re: Divergence for simple geometry room
Hello Yvan,
As you said, a simulation can be done by "least squares method over extended cell neighborhood" in Ver.6,
but the pressure difference flow simulation had a divergence problem.
In my case, pressure difference is just 0.6Pa. This is very small, but the result became divergent.
Best regards,
Tsubasa
As you said, a simulation can be done by "least squares method over extended cell neighborhood" in Ver.6,
but the pressure difference flow simulation had a divergence problem.
In my case, pressure difference is just 0.6Pa. This is very small, but the result became divergent.
Best regards,
Tsubasa
Re: Divergence for simple geometry room
Hello Yvan,
Do you think Ver.7 is more stable for computation than Ver.6?
(Idealy, I want to conduct a pressure driven flow by steady simulation (not URANS).)
If you think so, I want to try it with Ver.7.
If it is possible, every problem can be solved, which is posted in another post.
Best regards,
Tsubasa
Do you think Ver.7 is more stable for computation than Ver.6?
(Idealy, I want to conduct a pressure driven flow by steady simulation (not URANS).)
If you think so, I want to try it with Ver.7.
If it is possible, every problem can be solved, which is posted in another post.
Best regards,
Tsubasa