[M-B]

Hello everyone,

Unsteady simulation of a radial inflow turbine. Due to the pitch ratio between stator and rotor time transformation can not be applied without scaling the pitch.
The Fourier Transformation was used, considering two components per raw, but the following error show up:

| ERROR #999100267 has occurred in subroutine gKCsFCCsPS.
| Message:
|
| Unable to compute interface connectivity between the following
| domain interfaces:
|
| Phase Corrected domain interface : S1 to S1 Periodic
| Sampling domain interface : S1 to S1 Internal
|
| 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-12.

The ps mapping check tolerance has been changed to 1E-3 but the same error occurs.

Any idea on how to solve it ?

Cheers

[Opaque]

When using the Fourier Transformation model, you created a copy of the first passage using a Mesh Transformation step, correct ?

If you used the Rotation method, how many significant digits did you use to specify the Rotation Angle for the second copy ?

To minimize (probably eliminate) the round off error of the rotation transformation, it is always advised to use the Turbo Rotation and let the software compute the "exact rotation angle" internally from the different passage counts specified.

Good luck

[M-B]

Originally Posted by Opaque

When using the Fourier Transformation model, you created a copy of the first passage using a Mesh Transformation step, correct ?
Yes that is needed to have two components per row

If you used the Rotation method, how many significant digits did you use to specify the Rotation Angle for the second copy ?
Regarding the stator the blade number is 12, therefore no need to consider decimal

To minimize (probably eliminate) the round off error of the rotation transformation, it is always advised to use the Turbo Rotation and let the software compute the "exact rotation angle" internally from the different passage counts specified.
Thanks for this tip.

Good luck

The problem might be related to the use of CFX (beta) instead of the regular CFX. Even if no beta features are used, the CFX beta layout was leading to this error in the interface connectivity

[Opaque]

It is worth trying it. The message is very clear and it relates to what I just explained earlier.

I have seen it in the past, and using more accurate transformation resolved the problem. Keep us posted.

[M-B]

The error was due to the use of the component system CFX (beta). Instead of choosing the CFX (beta) on the component systems list I used the CFX and the simulation was running correctly. It was not a problem of accuracy in the trasformation but just a matter of using the correct component systems.

[TanWei]

Originally Posted by Opaque

It is worth trying it. The message is very clear and it relates to what I just explained earlier.

I have seen it in the past, and using more accurate transformation resolved the problem. Keep us posted.

Dear Opaque,
I've tried every method to solve this problem, based on the user manual and FAQ in CFD-online.
I generated the second instance by Turbo Rotation Transform and Rotation Transform by 16 digits, and even created the mesh with two instances right in the mesh generation software (Numeca-igg for example), the connection of Sampling Domain Interface are guaranteed. And each steady result of them which is used as the initial condition are calculated by double precision.
But the error still happened, I really don't know how to solve it. The case of mine is a shrouded single stage turbine, dos there anything to do with "ps mapping check tolerance"? And I cannot find the "ps mapping check tolerance" in "Expert Parameters" in CFX-Pre.
Could you please tell me how to do with it? I really have no idea how to do with it.
Sincerely Thanks