cero friction

[danielhoyos24]

Hi,

I have two steel plates with a contact to contact surface. 

How can I fix the parameters to obtain cero friction between the two plates?

Thanks.

[zhuangs]

You want to obtain zero friction, right?

Which analysis type are you using, Nonlinear or linear?  In nonlinear, you can use 'MES with Nonlinear Material Models' analysis type, and then define a contact pair with frictionless contact.

-Shoubing

[danielhoyos24]

Here is the model,

I tried to define the pair but it continue transpassing the other surface. I don´t know what i´m missing. I used a MES with nonlinear materials and defined the pair with frictionless contact.

Is there something I´m missing?

[zhuangs · Accepted solution]

In MES contact, the contact will be ingnored once a node exceeds the maximum penetration distance.

In your model, there is initial gap, the contact is not activated at the very beginning, and the time step size is large enough to make the contact nodes exceed the maximum penetration distance in the first step.

There are three ways to handle this kind of issue:

(1) Change load curve and use multiple time zone, to let the model move slowly within more steps before contact starts.  Such as

      Load curve: (0,0)-(40,1)     to      (0,0)-(2,0.00010-(40,1)

      Time zone: (40,20)             to      (2,10)-(38,20)

(2) Use a user-defined contact distance just exceeding the initial gap to activate the contact early, if ther initial gap is very small.  Such as 0.8001, as for the initial gap of 0.8

(3) Input a large value of maximum penetration.  Note that we should be very careful when we use this option.  The amount should account for the geometry of the model.

By the way, the obtain better solution, the mesh of Part 1 (bending deformation) should be smaller.  You can only reduce the mesh size of part 1.  Moreover, use 'Midside" nodes can help as well.

-Shoubing