## Search found 41 matches

31 Jul 2019, 13:52
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

I did the very same thing with Friction Contact = Logical True instead of Slide Contact = Logical True and get the same results, so I guess it didn't work because of the Normalforce instead of Displacement 3 to simulate the Normal Force.
31 Jul 2019, 11:20
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

That does work well! Thank you! So I guess the friction contact just does not work yet.
30 Jul 2019, 14:36
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

SlipForce = SQRT( SUM( NodalForce**2 ) - NormalForce**2 ) I am a little confused about this now that I looked at it closer. In my understanding NodalForce is a matrix with *number of dimensions* rows and *number of elements* columns, because this is how it is saved in ElasticSolver: LoadVector(1,1:n...
30 Jul 2019, 13:49
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

Right, the Slipload is the Force that is applied to the cube in tangential direction. The formula is correct, and I also traced "NodalForce" back to the ElasticSolver and it is really the value that you can set as BC as either Force/Surface Traction 1,2,3 or Normal Force/Surface Traction. Somehow th...
29 Jul 2019, 14:06
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

When I run friction.sif, somehow the plate does not move at all.

Shouldn't the slip load correspond to the force you apply on the cube? So in your friction.sif, 300000?
26 Jul 2019, 15:45
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

Turned out it works, but the force I applied was too low. I applied the static friction force (~0,03) as Surface Traction and because of it being too low nothing happened. Then I randomly put Normal Surface Traction = Real 300.0 at the front side of the cube (+Displacement 1 = Real 0.0 for the whole...
26 Jul 2019, 14:18
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

Ok.. so I've tried Force 2 and Normal Force at the back side of the cube and Surface Traction 2 and Normal Surface Traction at the front side of the cube. The cube starts rotating and does not only move in y-direction. I tried to put Displacement 1 = Real 0.0 for every side of the cube but then the ...
26 Jul 2019, 11:40
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

I am now trying to apply a Force or a Surface Traction to achieve the side motion instead of Displacement, I'll get back to you when I have some results.
25 Jul 2019, 14:39
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

So the cube trying to tip over is probably not the reason for the wrong forces, because the plate would not try to flip. That was your intention trying this, right? I finally managed to get my terminal output right and the calculation of Fdynamic and Fstatic is correct for normalforce and no side mo...
24 Jul 2019, 13:56
Forum: ElmerSolver
Topic: Contact Mechanics - Friction Test
Replies: 63
Views: 9265

### Re: Contact Mechanics - Friction Test

With gravity load it doesn't work for me either. The tipping over could be an effect, but usually it should not happen with the friction coefficent and normalload being quite low. The problem could be that the calculated Fstatic and Fdynamic are way too high. In my terminal output they are always WA...