Changing constraint values

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lampbus
Newbie
Beiträge: 1
Registriert: So 2. Nov 2014, 14:30

Changing constraint values

Beitrag von lampbus »

Hello, I am new here and new to FEA

I am enjoying exploring FEA through Z88 Aurora, and naturally I have a few questions that I cannot find answers to using google...

1. Can I change the value of an applied constraint force in the GUI without deleting and recreating the constraint ? This would be really useful to quickly try different pressures for example and re-calculate to see the results.

I assume that this can be done in one of the files, but I am not advanced enough to dig about in those yet.

2. Meshing : I have created a 'binocular load cell' beam to play with (based on a unit I built into an engineering project I designed). It has large cuboid blocks on each end, and much thinner parts where the strain gauges go.
When I generate a mesh that is fine enough at the thin/curved parts there is far too much detail in the blocks. Display movement takes forever.
If I generate a course mesh, and then refine by selecting elements in the thin areas, the curves are far too coarse.
Is there a way to 'un-refine' selected element groups ?

3. Projected load : I have experimented with different load types on a curved surface (a cylinderical hole). I am confused by the differences between 'load' and 'projected load'.

load 1000 in z on hole = 8.12e-2 displacement
projected load 1000 in z on hole = 8.10e-2 displacement

I would have expected a larger difference...or is this correct ?

I assume that the fact that half of the hole faces are away from the force and half towards the force is ignored by the system. To correctly simulate loading eg a shaft in a hole, only half the hole should be selected.

Hoping for guidance...
PascalD
Alumni
Beiträge: 23
Registriert: Mi 6. Nov 2013, 08:19

Re: Changing constraint values

Beitrag von PascalD »

Hello lampbus and welcome to Z88!

Generally we advise you to consult the english documentation which you can find in the help menu. This will probably be more helpful than using google.

1. It is not possible to change a constraint value without recreating it. But you can create a number of different constraints with different values and select which one is active by checking the box next to the constraint.

2.1 If movement speed is your main concern, try activating "boundary view" and "quick view". They will speed up moving the model significantly.
2.2 It is not possible at the moment to "un-refine" a mesh. You can only remesh the model and refine certain areas anew.

3. The maximum displacement (which should occur at the bottom) is not a very good way to compare load/projected load, since the displacements on the sides will be most affected by the differences in the load mechanics.

I hope this helps!

PascalD
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