mesh quality requirement

Fluent

orthogonal quality

minimum orthogonal quality>0.01

Aspect ratio:

No specific value, avoid sudden and large changes in cell aspect ratios in areas where the flow field exhibit large changes or strong gradients

Skewness

<0.95

ANSYS Meshing

For surface mesh, Min orthogonal quality 0.4-0.5

For volume mesh

minimum orthogonality > 0.15

maximum skewness < 0.95

For orthogonal quality below 0.1, divergence is likely

ICEM

Pre-Mesh quality

Determinant >0.3

Angle, (18, 90)

Warpage < 45 degrees

Comments

TUI Fluent

‎ Table of Contents 1. TUI 1.1. Examples 1.1.1. Steady 1.1.2. Unsteady 1.2. discretization schemes 1.3. Turbulence model 1.4. Reference 1.5. Save residual 1.6. Journal 1.6.1. record journal GUI 1.6.2. The interactive TUI inside Fluent helps: 1.7. define 1.7.1. boundary-conditions 1.8. change rotational velocity of moving reference frame 1.8.1. batch model 1.8.2. interactive console TUI 1.9. set background color 1.9.1. invalid command [background] 1.10. syntax 1.11. Batch model 1.12. Boundary condition 1.12.1. Inlet BC 1.13. Animation/residual/monitor on cluster 1.14. Solver 1.15. Change pressure-velocity-coupling model in batch mode 1.16. time step size 1.17. Modifying the View 1.18. initialization 1.19. discretization schemes 1.20. Set under relaxation 1.21. log of execute makefile 1 TUI keywords: Background Execution on Linux Systems, journal file Programming language : Scheme , as a Lisp d...

Fluent Error FAQ

Process 1928: Received signal SIGSEGV. Running on windows Mesh size, 12M serial Error: received a fatal signal (Segmentation fault). Error Object: #f parallel select 4 processors error information Node 0: Process 1928: Received signal SIGSEGV. Node 5: Process 2824: Received signal SIGSEGV. MPI Application rank 0 exited before MPI_Finalize() with status 2 The fl process could not be started. Reason This is primarily a Windows issue. If running Fluent with -t1 or higher number of processes and leave the session for an extended period of time (2-20 hours), it receives the following message in the console: ...

Turbulent viscosity limited to viscosity ratio of 1e+05

** Turbulent viscosity limited to viscosity ratio of 1e+05 *** reason The possible *causes* for large turbulent viscosity ratio include: - Bad initial conditions for the turbulence quantities (k and e) - Improper turbulent boundary conditions - Skewed cells *** solution If the problem is not caused by *bad mesh*, then *the beginning of the phenomena* can usually be avoided by: -Turn off solving *turbulence equations* for the first 100-200 iterations -Turn on turbulence and continue iterations If the problem occurs *in the middle of the iteration process*, then use the following procedure: - Stop the iteration - Turn *off* all equations except the *turbulence equations* - Increase turbulence under relaxation factors (URFs) (k and e) to 1 and iterate for 20-50 iterations - *Turn back all equations* and reduce the turbulence URFs to 0.5-0.8 and then continue iterations - Repeat the above steps for several times For *faster convergence*, it might be useful to obtain an initial solution wit...

ANSYS

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