questions about the coronary mesh

[yan qing]

Hello,
I want to create a mesh for a coronary project,and I follow the guide from the website http://simvascular.github.io/clinicalCase3.html#model.
The guide says "Once you have done this, run the mesher. Hopefully, you should get a mesh with roughly 300,000 to 1 million elements."
But I have some questions about the mesh:
1.What should I do to make sure that the mesh I create is suitable for my project?
2.If I get a mesh with roughly 300,000 to 1 million elements, Grid independence test is needed for the coronary project?
3.I use the Adapt mesh model, but I didn't get the adapt solution as the guide say.
"Also the new adapted solution is create in [proj-path]/Meshes with a name adapted-restart.[step number].1"

Thanks in advance,
Yan

[David Parker]

Hi Yan,

1.What should I do to make sure that the mesh I create is suitable for my project?

The mesh must be fine enough to correctly resolve the flow features produced by your geometry and boundary conditions.

2.If I get a mesh with roughly 300,000 to 1 million elements, Grid independence test is needed for the coronary project?

People typically run several simulations using different mesh refinements to determine the appropriate mesh size.

3.I use the Adapt mesh model, but I didn't get the adapt solution as the guide say.

I'm not sure what you mean by Adapt mesh model. Do you mean adaptive meshing in the SV Mesh Tool? The coronary project you cite does not mention adaptive meshing.

Cheers,
Dave

[yan qing]

Hi Dave:
Thank you for your reply.
1.The mesh must be fine enough to correctly resolve the flow features produced by your geometry and boundary conditions.
How can I make sure that the mesh is fine enough to correctly resolve the flow features? too many elements will consume to much time to run the simulation.
2. People typically run several simulations using different mesh refinements to determine the appropriate mesh size.
I have to run about 15 coronary cases, have I run several simulations using different mesh refinements in every case? Or is there a simple way to determine the appropriate mesh size for the 15 coronary cases.
3.I'm not sure what you mean by Adapt mesh model. Do you mean adaptive meshing in the SV Mesh Tool? The coronary project you cite does not mention adaptive meshing.
Sorry, I want to say is the Adapt mesh module in the SV Mesh Tool, and I used the former simulation results to generate the adapt mesh,but I did't get the new adapted solution as the guide says
"In the end, a new adapted mesh is created under the "Meshes"in Data Manager. Also the new adapted solution is create in [proj-path]/Meshes with a name "adapted-restart.[step number].1". You can use the adapted mesh and the adapted solution as IC file to create a new job to run simulation."

Thanks
YAN

[GUANGYU ZHU]

Hi, Yan

I think you need to carry some mesh independence experiments, and verification and validation would be recommended for CFD simulation. There are some practically rules to follow, you may refer to the references below:
1. Overview of CFD Verification and Validation: https://www.grc.nasa.gov/www/wind/valid ... rview.html
2. Standard for Verification and Validation in Computational Fluid Dynamics and Heat Transfer: https://www.asme.org/codes-standards/fi ... t-transfer
3. Verification and validation in computational fluid dynamics: https://www.sciencedirect.com/science/a ... 2102000052

Best Regards,
Guangyu

Hi Dave:
Thank you for your reply.
1.The mesh must be fine enough to correctly resolve the flow features produced by your geometry and boundary conditions.
How can I make sure that the mesh is fine enough to correctly resolve the flow features? too many elements will consume to much time to run the simulation.
2. People typically run several simulations using different mesh refinements to determine the appropriate mesh size.
I have to run about 15 coronary cases, have I run several simulations using different mesh refinements in every case? Or is there a simple way to determine the appropriate mesh size for the 15 coronary cases.
3.I'm not sure what you mean by Adapt mesh model. Do you mean adaptive meshing in the SV Mesh Tool? The coronary project you cite does not mention adaptive meshing.
Sorry, I want to say is the Adapt mesh module in the SV Mesh Tool, and I used the former simulation results to generate the adapt mesh,but I did't get the new adapted solution as the guide says
"In the end, a new adapted mesh is created under the "Meshes"in Data Manager. Also the new adapted solution is create in [proj-path]/Meshes with a name "adapted-restart.[step number].1". You can use the adapted mesh and the adapted solution as IC file to create a new job to run simulation."

Thanks
YAN

[yan qing]

Hi,Guangyu
Thank you for your advice.
I will read the papers you list and carry the mesh independence experiments.
If I have questions, I hope that I could get your suggestions.


Thanks,
Yan

[David Parker]

Hi Guangyu,

Very nice references to verification and validation for CFD simulations! I will put them in the SV documentation at some point.

Thanks!
Dave