"contact" beam mesh
"contact" beam mesh
(OP)
Hi,
Here's a question regarding a beam meshtype.
I'm trying to simulate the maximum displacement and stress of an arch shaped structure to be able to define the best way and place of stiffening the structure with tension lines.
The thing being, that because of the shape, the archway tends to deflect into an opposing part.
The question is, is there a possibility to make a "contact set" type interaction between the two parts, like what can be done with a solid mesh.
My guess is that this won't be possible, seeing as the fundamentals of the meshtype don't make it possible to recognise touching of parts seeing as it has no "faces".
Hopefully someone could give me a hand with this one.
Model:
htt p://files. engineerin g.com/getf ile.aspx?f older=558b 385a-8e3a- 4761-b4da- 19c4f0ed41 24&fil e=arch.bmp
Beam mesh:
http://f iles.engin eering.com /getfile.a spx?folder =809b3cb1- ea7b-41b5- ae9c-c0f4b 83b6162&am p;file=Bea m_arch.bmp
Here's a question regarding a beam meshtype.
I'm trying to simulate the maximum displacement and stress of an arch shaped structure to be able to define the best way and place of stiffening the structure with tension lines.
The thing being, that because of the shape, the archway tends to deflect into an opposing part.
The question is, is there a possibility to make a "contact set" type interaction between the two parts, like what can be done with a solid mesh.
My guess is that this won't be possible, seeing as the fundamentals of the meshtype don't make it possible to recognise touching of parts seeing as it has no "faces".
Hopefully someone could give me a hand with this one.
Model:
htt
Beam mesh:
http://f






RE: "contact" beam mesh
However I'd have thought that pretzeling is exactly one of the failure modes you are trying to prevent, soartificially suppressing it seems iunproductive.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: "contact" beam mesh
The model is not pretzeling. That's the scaling on displacements you are seeing. The biggest deflection is .05mm.
CoasterChris
One of the things experienced FEA analysts do is use symmetry. Place boundary conditions that mimic the other side.
Contact occurs between nodes even when using surface to surface contact. The element only knows what is going on at the nodes and when surface to surface contact is used the software internally creates forces on the nodes involved in contact.
Are those really beam elements or is it just a solid mesh of a bunch of tubes?
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: "contact" beam mesh
sure sounds like pretzeling to me.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: "contact" beam mesh
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: "contact" beam mesh
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: "contact" beam mesh
Look at the plot. My guess is that this is a roller-coaster support. Don't know what gives me that thought, maybe the OP's handle. So that tube may stand ten or more feet in the air. If you look carefully at the very top in the displaced plot the two sides are not attached to each other. This wouldn't be so in the actual application because whatever applies loads to these towers would hold them together. Yet the two triangular sections at the top are embedded in each other, but the legend on the right says they only moved .0007in.
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: "contact" beam mesh
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: "contact" beam mesh
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
"Node news is good news."
RE: "contact" beam mesh