2D mesh, line contact, Radioss nichtlinear analysis

Altair Forum User

Hi!

 

Could ssomeone help with the following problems please? I defined two surfaces with shell elements and an imposed displacement in the middle of the circle(-2,044mm in Y axis) 

I don't know how to define correctly the contact between these two meshes. I tried it with TYPE7 and TYPE11 as well. I got the same result.

<?xml version="1.0" encoding="UTF-8"?>

Which type should i use and how to properly define them?

 

There is also a gap between meshes and the two pionts(the top point of the rectangle has another displacement as the bottom point of the circle with IMP DISP ). How is that possible? Why is there a gap between meshes? I defined shells with thickness 15.

<?xml version="1.0" encoding="UTF-8"?>

 

Thanks in advance!

 

gopal_rathore

Hi,

This seems to be an edge to edge contact. Thus type 11 is fine. Try to reduce initial gap between the two mesh..

The two displacements are coming different as the circle has to move certain displacement before making a contact with the blue part. Thus its displacement is coming higher as you have higher initial gap between two meshed parts.

Altair Forum User

Hi!

 

I just checked tutorial video:  https://youtu.be/-eoYLVLz0dA?list=PL1u26y75SCrA_BOCLaSewVCNY7xRvCTnA&amp;t=1044

 

how to define type11. Reduced the gap for 0.5mm, as IMP DISP i defined 0.55, so at the top point of the rectangle i should get 0.05mm, but as you can see below is much higher.

What can be the problem?

<?xml version="1.0" encoding="UTF-8"?>

gopal_rathore

Hi,

You can define type 11 through entity sets and set LINE as card image. Can refer some tutorial also.

Or if using hyper crash simply select the components and assign TYPE 11 contact .

 

What I understand is you have physical gap of 0.5 mm but have you given any Gap min if not given, the solver will automatically calculate Gap min. refer help file for this. If you have physical gap of 0.5 mm give Gap min., also as 0.5 mm and then run

 

 

Altair Forum User

Hi! Could you please send me the tutoriial of Type11? I could find only the video, where line components are made with 'FIND EDGE' command.

 

Yes you understand right. I just tried it with 0.5mm GAP min but in this case it gives bigger displacement at the top point of rectangle. See the picture below.

<?xml version="1.0" encoding="UTF-8"?>

 

Could you also send a tutorial for the definition of parameteres? With online help i used the followings, it gave me the same result.

 

 

Thank you!

<?xml version="1.0" encoding="UTF-8"?>

Altair Forum User

Hi,

Check this RADIOSS video learning series: https://m.youtube.com/watch?v=FjErJVigVJU&amp;index=2&amp;list=PL1u26y75SCrA_BOCLaSewVCNY7xRvCTnA&amp;t=14s

Creating Type 11 contact and the various contact parameters are covered here.

Also they have released a free RADIOSS ebook which is very useful for beginners. Many FAQs, tutorials, theoretical background....etc are well covered in that.

pohan

Hi. Try gap min = 0.1 I think you will get a better result.