|
[Sponsors] |
February 12, 2019, 20:48 |
multi-block mesh problem
|
#1 |
New Member
Join Date: Dec 2017
Posts: 20
Rep Power: 9 |
Hi all,
I am working on simulating a large pond with several inlets and outlets. Thus, I use multi-block mesh, but a velocity disturbance starts to grow on the inter-block boundaries and spread throughout the domain. For finding the source of the problem, I decided to make the problem simple, so I simulated a 10m*10m*2m pool with 0.9 water elev. without any inlet or outlet. There is no wind, and no initial vel. It has 2 linked mesh blocks with sizes of 0.5m and 0.25m (Aspect ratio is 1 for both of them). All of the BCs were left as default (symmetry). We expect the velocity remains zero, but after 1000 sec the disturbance starts and after a few seconds it takes over the whole domain. I already increased Inter-block boundary type coefficient (alphamb), but it didn’t help. Smaller mesh size and different turbulence model didn’t help either. Other configurations of mesh blocks (nested or overlapping) also cause the same problem Does anyone have an idea why this simple simulation has this error? Thank you! |
|
February 13, 2019, 18:50 |
|
#2 |
New Member
Ali
Join Date: Dec 2018
Posts: 3
Rep Power: 8 |
ِDear user
That is due to interpolation error between blocks. By choosing 1:2 mesh size ratio, and increasing alphamb, and putting the interblock boundary somewhere with less p and v gradient you can only decrease it. To me this is a big problem of Flow3D that needs to be resolved!!! F3D guys may have a better response for you. |
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
[foam-extend.org] Foam-extend-3.1 on RHEL: mesh problem | lxwd | OpenFOAM Installation | 4 | March 25, 2017 17:10 |
[mesh manipulation] Importing Multiple Meshes | thomasnwalshiii | OpenFOAM Meshing & Mesh Conversion | 18 | December 19, 2015 19:57 |
[Gmsh] 2D Mesh Generation Tutorial for GMSH | aeroslacker | OpenFOAM Meshing & Mesh Conversion | 12 | January 19, 2012 04:52 |
fluent add additional zones for the mesh file | SSL | FLUENT | 2 | January 26, 2008 12:55 |
How to control Minximum mesh space? | hung | FLUENT | 7 | April 18, 2005 10:38 |