High Speed Impact Interface Suggestion

Ovunc2

Hello, 

I am examining the case of a very thin part high speed impact another part. The material of both parts is steel. 

What do you recommend as a contact and element type? 

Thank you. 

Best Regards, 

Ovunc

Guilherme_Brandao

Hi,

Are you using Shell or Solid elements?

There are two contact types that you may use. Type 7 is recommended when using shells since it does not work with zero gaps. Type 25 is recommended for solids since it does work with zero gaps. 

Another important difference is that Type 7 has a nonlinear stiffness while Type 25 is linear.

Please, check the following references for more information:

• YouTube video - Contact Definitions for Radioss
• Type25 Documentation
• Type7 Documentation

I hope it helps,

Kind regards,

Guilherme Brandão.

Mathis

Hi, 

If you have solid elements and element erosion, the type24 interface is the way to go. Solid element erosion is not available (yet) in type25 interface. 

Regards,

Mathis. 

Ovunc2

Hi, 

Thank you @Guilherme Brandâo and @Mathis Loverini. 

My component is very thin. There are some examples in the literature where 3D elements are used for such problems. That's why I used a 3D element instead of a shell element. I used 2-3 rows of elements along the thin thickness. I used type 7 as contact. ( There is no solid element erosion.) 

I want to use the stresses I obtained from the impact for life prediction in Hyperlife. But, since the stresses are calculated to be very high, the lifecycle calculated to be very short, which is far from reality. So, I think there is an error in the stress levels calculated in the elements in the model I created.

Apart from contact formulations, what else do you recommend I try?

Thank you. 

Best Regards, 

Ovunc