Learning Forum

[sna]

Hi!

I have a test model of a flange and pipe (one single model) with 6 bolt holes. The total length is 1000mm

A perpendicular load of 5000N is defined on the tip of the pipe

the 6 bolt holes are fixed.

For the full model: the reaction moment is pretty much as expected with near zero moment about Mx and My. The total reaction moment is almost a perfectly aligned with Z axis

For the half symmetric: the reaction moment about Mx and My is suddenly substantial and the total reaction moment is not aligned with Z axis at all.

Any Idea why the symmetric version is not reporting the same?

• load is halved for the symmetric case
• both frictionless and symmetry constraints have been tried. Both respond the same.
• Large displacement is enabled. 

 

[ErKo]

 

Hi

If set up correct I would assume it will give same results (perhaps post the model here if not – confidential and not ITAR, and some forum members can look at it – peteroznewman – Ansys. emp. can not help with that here in the forum ).

Or even better send it to your channel partner (EDR Medeso AB), and they will be able to look and tell you why it is so.

All the best

Erko

 

 

 

[Deepak]

As a recheck, you can try defining symmetry (remove the symmetric region) by adding a frictionless support at the symmetric face. Thanks, Deepak

[ErKo]

Hi Deepak - user mentioned he has done that see his info below:
I would suggest to post the model here and other forum members can have a look or send it to EDR Medeso Channel P.

• both frictionless and symmetry constraints have been tried. Both respond the same.

[sna]

Hi Deepak!

I already tried that

Here is my setup:

 

[ErKo]

Hi

 

Can you please send your model to EDR medeso as you are supported - they can see why this is (we can help also if needed).

 

Thank you

Erko

[spamanon]

This is expected to balance moments. Here is an example similar to yours, with calculations.

The Remote Displacement x-direction Moment Reaction about the x-axis is: -12.961 lb in.
The Frictionless Support x-direction Moment Reaction about the x-axis is: -3.3611 lb in.
The Frictionless Support x-direction Moment about the Remote Point center due to z reaction force is: 9.4838*0.42857 = 4.0645 lb in

The total support reaction is therefore: -12.961 - 3.3611 + 4.0645 = -12.258 lb in

The x-direction Moment about the Remote Point center due to applied force is: 13*0.94286 = 12.257 lb in 

So moments are balanced.