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incorrect results -- 2D-Axissymmetric modeling - averages do not respect the 3dimensionality
Posted 5 mars 2014, 09:00 UTC−5 Version 4.4 2 Replies
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If I use a "2D axsissymmetric component" respresenting for example a cylinder.
Then Definitions/Component Couplings/Average results in the average of the 2D cross-section but does not calculate the average of the 3D component represented by the "2D axsissymmetric component" approach. As this is a simplification for faster modeling with less resources, I feel that the result is misleading - not to say incorrect. In the true 3D world the outer areas of a cylinder have more volume per radius unit than the inner areas. This fact is neglected as an average over the 2D cross-section weights each radius unit equal.
What is the inteded way to correctly calculate average values within the "2D axsissymmetric component"
I attach a file with this calculations.
Then Definitions/Component Couplings/Average results in the average of the 2D cross-section but does not calculate the average of the 3D component represented by the "2D axsissymmetric component" approach. As this is a simplification for faster modeling with less resources, I feel that the result is misleading - not to say incorrect. In the true 3D world the outer areas of a cylinder have more volume per radius unit than the inner areas. This fact is neglected as an average over the 2D cross-section weights each radius unit equal.
What is the inteded way to correctly calculate average values within the "2D axsissymmetric component"
I attach a file with this calculations.
2 Replies Last Post 5 mars 2014, 09:48 UTC−5
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Posted:
1 decade ago
Hi,
Probably you did not select the "Compute integral in revolved geometry" check box.
Regards,
Henrik
Probably you did not select the "Compute integral in revolved geometry" check box.
Regards,
Henrik
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Posted:
1 decade ago
Yes, You are correct! Thank You!
I never expected I had to check an extra box to get the correct results.
A problematic point in correcting the variable expression is, that I have to fill in the calculated variable name into "Point probe expression" for new with an arbitrary change inbetween, to make the program find out, something in the expression has changed with the variable.
I never expected I had to check an extra box to get the correct results.
A problematic point in correcting the variable expression is, that I have to fill in the calculated variable name into "Point probe expression" for new with an arbitrary change inbetween, to make the program find out, something in the expression has changed with the variable.