[OREO]

Dear all,
I'm faced up with a problem that keeps troubling me these days. I've tried all I can do but it didn't help.
When I'm applying Fourier Transformation to calculate the unsteady flow field of a single stage shrouded axial turbine, the CFX solver called an error that
+--------------------------------------------------------------------+
| ERROR #999100267 has occurred in subroutine gKCsFCCsPS. |
| Message: |
| |
| Unable to compute interface connectivity between the following |
| domain interfaces: |
| |
| Phase Corrected domain interface : rotpass |
| Sampling domain interface : rotpassin |
| |
| for this serial/partitioning run. Likely causes are: |
| |
| 1) The mesh has been transformed using single precision |
| arithmetic at some point. |
| 2) The single precision solver/partitioner is being used instead |
| of the double precision solver/partitioner as recommended for |
| the Fourier Transformation model. |
| |
| If 2) is not the case please increase the expert parameter |
| "ps mapping check tolerance" to a value larger than the current |
| value: 1.000E-012. |
| |
+--------------------------------------------------------------------+

+--------------------------------------------------------------------+
| An error has occurred in cfx5solve: |
| |
| The ANSYS CFX partitioner exited with return code 1. |
+--------------------------------------------------------------------+

The second passage is generated by Turbo Rotation, and the connections are fine. In order to make sure, I exported two-passage mesh in the grid generation software, but the error still happened.
After reading the advice on other blogs, I'm sure that the CFX is opened directly in the system, for which the problem might not be caused by CFX(beta), or the beta component is referred to the .beta variable of CFX-post? And I don't know how to switch off the calculation of .beta variable (Density .beta, for example), even after I read the user manual.
The steady result which is used as initial files are calculated as double precision as well.
However, I enlarged the "ps mapping check tolerance" in the CFX-Pre to 1E+12, but the problem still happened.
Can anyone helped me with the problem? Really really thank you.

[Opaque]

The guidelines indicate that the steady-state case should be a similar setup as the transient, i.e. two-passages.

The two passages are created by importing the original passage into CFX-Pre, apply a mesh transformation using Turbo Rotation indicating the number of passages in 360, the number of passages in the mesh, i.e. 1, and the number of passages to be modeled, i.e. 2.

If you use the preview mode in the mesh transformation editor, you can also zoom into the interface to verify the pitch has been computed correctly and periodic surfaces are touching.

This is how I have done it in the past. Hope it helps

[OREO]

Originally Posted by Opaque

The guidelines indicate that the steady-state case should be a similar setup as the transient, i.e. two-passages.

The two passages are created by importing the original passage into CFX-Pre, apply a mesh transformation using Turbo Rotation indicating the number of passages in 360, the number of passages in the mesh, i.e. 1, and the number of passages to be modeled, i.e. 2.

If you use the preview mode in the mesh transformation editor, you can also zoom into the interface to verify the pitch has been computed correctly and periodic surfaces are touching.

This is how I have done it in the past. Hope it helps

Dear Opaque,

Thanks for your reply.
I've tried this method to generate the second passage.

It can be seen slight unmatched in the sampling domain interface, at first, however these face grid was identified as initial surface by CFX-Pre software.

In order to insurance purposes, I generated two-passage mesh in Numeca-igg software which can make sure the sampling domain interface is connected directly.

All these mesh is calculated for the steady simulation as the initial condition. But the unsteady simulation still cannot be carried on.

Anyway, we really appreciate it that you gave the advice.

[Opaque]

If you see a gap between the 2nd mesh passage and the first one in the viewer, the surface meshes are not rotationally periodic and unfortunately incorrect.

For verification, I would take any of the turbomachinery tutorial meshes and create a 2nd copy as described earlier, and check the viewer for the gap. If it is not there, you know the source of the problem: the meshing application you are using. If that is the case, I would look into the application settings to improve the rotationally periodic surface meshes.

[OREO]

Originally Posted by Opaque

If you see a gap between the 2nd mesh passage and the first one in the viewer, the surface meshes are not rotationally periodic and unfortunately incorrect.

For verification, I would take any of the turbomachinery tutorial meshes and create a 2nd copy as described earlier, and check the viewer for the gap. If it is not there, you know the source of the problem: the meshing application you are using. If that is the case, I would look into the application settings to improve the rotationally periodic surface meshes.

Dear Opaque,
The mesh generation software is Numeca-IGG/Autogrid5, the same software that my colleague used for FT unsteady simulation, who made a success.
The surface grid connection of sampling domain interface is guranteed in IGG interface, which case is made two-passage mesh directly.