Alignment error in engine simulation
 

1850 WARNING:
there may be an alignment error.
The maximum dot product of the motion vector with a non-moving triangle's normal vector is 1.166965e-03.
For properly aligned moving surfaces, this dot_product should be less than 5.0e-4


1851 WARNING: The boundary type that appears to not be aligned is WALL, and it is attached to boundary 1, which is moving.

The triangle of maximum alignment error is centered at -6.137263e-03 4.243868e-02 -3.186973e-02



Hi

What can be a solution for this error in engine simulation. I tried to project vertices from the piston to head but I cant find any alignment error. I can run the simulation with this error/warning, but when I turn on monitor points the simulation just crashes.

Can you please let me know what is boundary 1? This error is typically a geometry related issue. I suggest make sure that you are using correct valve axes. Can you please check that.

Hi Chaitanya


Thank you for the reply. The error was geometry related. The geometry has just a piston and head. I was able to rectify that by projecting the curve from piston to head.

Alignment error in engine simulation
 

Hello,
The problem you have encountered is certainly geometry related, but I have not tried rebuilding the methods suggested to solve this problem (such as rebuilding the cylinder liner with the loft command) and unfortunately it did not work.

If you were able to solve this problem, can you describe in detail how you did it?

Hello Ibrahim,

Cylindrical liners must be rebuilt with the Create > Triangle > Sweep edges option, not the Loft edges option. This will ensure liner triangles are perfectly cylindrical along the piston motion axis provided (Sweep direction). Starting from the piston edge, sweep a single set of liner triangles over a sweep amount slightly greater than your stroke. Connect the open edge of the swept triangles with the open edge on the head with the Loft edges option to close the geometry.

Pay attention to the boundary IDs in the warning messages. If the IDs correspond to the valve boundaries, the same needs to be done for valve stem boundaries along the valve motion direction.

We recommended you take a look at our Piston and Valve Setup training session, available at our downloads page. This session as part of our CONVERGE for IC Engines course guides users on how to construct moving/deforming boundaries.

Sincerely,

Thank you very much for your answer, Kislaya.


I would also have one more question. I am currently using Converge version 3.2. But the license of Converge software belongs to a friend of mine. I access the download and training center with his account. However, I would like to have an account of my own. I registered to the download center, but it is not active, how can I resolve this issue.

Thank you very much for your guidance.

This time when I did this problem as you stated, it worked. However, I do not have access to the download center you mentioned. I have done the registration process, I am waiting for it to be activated for access, but access has not been activated. Can you support me on this issue?

Sincerely regards