Warning with Matrix27

[meshparts]

Hello!

I have a fe-model that uses matrix27 elements with keyopt(3)=4 (defines stiffness matrix). It works just fine. But:

I get the following warnig if I save model as CDB-File and then read it back in:

For element type= 5 (MATRIX27),KEYOPT(3) = 0 is invalid and will
generate no matrix unless a KEYO or another ET command is issued
making KEYOPT(3) = 2,4,or 5.

When listing the element types, the keyopt(3) is set to 4, as it should be!

So why this warning??

Thanks!

 

[Drej]

I use cdwrite regularly for archiving of my large models, and have found that it does not always write out models correctly. I have found that it's often better to write out using the UNBLOCKED format in the cdwrite command, although of course it's slower to read in. Give it a try. Also try using numcmp prior to the cdwrite command just to make sure the model numbers are reasonable.


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[meshparts]

Thanks Drej, but that wasn't it...

I must say, it's very curious.

Although after reading the cdb-File and after I get this stupid warning, I list the element types and I see, that the Matrix27 element has the right key option.

And the solution seems to be okay...

Regards,
Alex

 

[meshparts]

I looked in the CDB File with an Text editor and it is clear now, why:

Ansys sets the key option for Matrix27 AFTER it defines the Element Type:

ET,6,27
KEYOP,6,3,4

If I change the two line above with this one:

ET,6,27,,,4

I get no warning anymore!