Learning Forum

[Ines_]

Hi everyone,

I am trying to do a load case study in which I apply a pressure, that is common to every load case, and then I apply a different pressure each time. For this, I am following the steps in: https://drdtechnology.wordpress.com/2016/05/24/restarts-in-ansys-mechanical-can-save-time-and-effort/

The image below shows the first load case: the red line is the common pressure and the green line is the load case.

When I run the this load case (using restart information), I don't feel like my model is taking that preassure into account but that only the common pressure is being taken into account. To sum up, I think ANSYS just ignored my load case pressure.

[mrife]

the image mentioned in your question did not make it to the post...can you please post that image? Mike

Update: looks like this may be a Forum issue as the page is still trying to load....

[peteroznewman]

Yes, for at least the last 5 days, I have noticed huge delays in images loading in posts. It seems to be intermittent, not a consistent problem.

[mrife]

Can you give/show the details of the two pressure loads? I suspect that they are bolt applied to the same set of faces. Which is not allowed - an element face can only have one load applied. If this is the case check the Details of the load definitions. One can be applied directly to the element faces, the other via surface effect element.
What do the reactions add up to - that should be a cut-and-dried answer to what loads are applied.
Mike

[Ines_]

. Thats it! I applied both pressures to the same surface (via surface Effect). I'll try your approach and keep you updated.
Also, I think I didn't explain my other doubt correctly. My question is if it is possible to get the value of the pressure is being applied to the model (to a node, a surface,...). I've put the question in a separate post because it is not related to this post: /forum/discussion/35745/check-pressure-that-is-being-applied-to-a-model/p1?new=1
Thank you for your help!
In├®s

[mrife]

Actually that should be fine as different surface effect elements should have been used (never hurts to verify!). Before getting into what the applied load is at every element, let's do a basic check and compare the reaction forces to the applied loads. Do they make sense?
Mike

[Ines_]

!
I am trying to get them with a Force Reaction probe throught Geometry Selection and choosing one of the faces I am applying the pressure on but I am getting "A result is invalid with the current output control settings" without any other clue. I am pretty new to Ansys so not sure what's the problem.

[mrife]

Well, the force reactions are at the boundary condition(s). Not the applied loads. MIke

[Ines_]

!
These are the reaction forces at the two last seconds of the analysis, in which I am applying 10Pa (constant). I am not sure on how to explain the results because:
I am applying the pressure in an element and the Boundary condition (a fixed support from which I am getting the Reaction Forces) are in another different element (bounded to the former by a contact definition). Is this a problem?
Also, my fixed support is applied in two surfaces. To give you an idea, my model looks like a pipe with fixed ends. So, the values in the table, show the total of the reaction forces of both surfaces?
Last, the fixed surfaces have the same area (1,83*10^-5)

[mrife]

so, we need to know the area of the face(s) the pressure is scoped in order to compare the applied load (force) to the reaction forces.