How to check hourglass and contact energy for every part or every contact?

Altair Forum User

Hello everyone,

 

The total hourglass energy and contact energy can be checked by reading T01 file. However, can the hourglass energy be checked for every part or can the contact energy be checked for every contact? How to set up it? This is helpful to focus on the problem part or problem contact.

 

Best Wishes

Roy

Altair Forum User

Hi Roy,

Please create output block for every part and interfaces. For recalling interfaces in output block select groups from the menu in output block. Select all the parts and contacts defined and click Create and click Edit. In the card,for Num_Variables, input as 1 and for variables provide DEF, so that all default output variables are requested.

The steps can be seen in this webinar: https://www.youtube.com/watch?v=2ChWJbGhCVQ&index=7&list=PL1u26y75SCrA_BOCLaSewVCNY7xRvCTnA

 

 

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Altair Forum User

Hi George P,

 

Thank you. I'll try it.

 

Best Wishes

Roy

Altair Forum User

Altair Forum User said:

Hi Roy,

Please create output block for every part and interfaces. For recalling interfaces in output block select groups from the menu in output block. Select all the parts and contacts defined and click Create and click Edit. In the card,for Num_Variables, input as 1 and for variables provide DEF, so that all default output variables are requested.

The steps can be seen in this webinar: https://www.youtube.com/watch?v=2ChWJbGhCVQ&index=7&list=PL1u26y75SCrA_BOCLaSewVCNY7xRvCTnA

 

 

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Hi George P,

An error was met when I use the method you mentioned for a rigid body. So how to output kinetic energy for a rigid body?

ERROR ID :          760

** ERROR TRAPPED

Best Wishes

Roy

Altair Forum User

Hi Roy,

If you want to plot the time history of rigid elements, select rigid elements using the elements option from the output block menu. Please search in Help Menu for /TH/RBODY which will give the details on the output variables for rigid body. You can select the rigid component using comps option from output block and can plot the KE. 

Can you please share the model file and .out file.

Altair Forum User

Hi George P,

Thank you for your reply, I'll try it myself.

It seems that the contact energy of each interface cannot be output. The keyword /th/inter only outputs contact force, no contact energy output. Is there any method to check contact energy for each interface so that problem interface can be found out?

 

Best Wishes

Roy

Altair Forum User

Altair Forum User said:

Hi Roy,

If you want to plot the time history of rigid elements, select rigid elements using the elements option from the output block menu. Please search in Help Menu for /TH/RBODY which will give the details on the output variables for rigid body. You can select the rigid component using comps option from output block and can plot the KE. 

Can you please share the model file and .out file.

Hi George P,

 

From the help manual, /TH/RBODY only saves force,moment and rotation. The kinetic energy of the rigid body is not contained.

As far as I know, the rigid component in radioss is not a part (with none card image), and the energy can be saved with /TH/Part, so how about rigid component?

 

Thank you

Roy

Altair Forum User

Hi Roy,

/TH/INTER will output only contact forces. You can output only global contact energy. Using ANIM/VECT/CONT you can generate animation files containing vectorial data for the contact forces. For the rigid component (which will have a part card image) you can create an output block using components option.

Altair Forum User

Altair Forum User said:

Hi Roy,

/TH/INTER will output only contact forces. You can output only global contact energy. Using ANIM/VECT/CONT you can generate animation files containing vectorial data for the contact forces. For the rigid component (which will have a part card image) you can create an output block using components option.

 

Hi George P,

 

1. As far as I know, the rigid component in radioss cannot use part as card image. So how to understand your saying 'the rigid component (which will have a part card image)'?

2. If contact energy for each interface cannot be output, how to find out the problem interface which makes global contact energy too large?

 

Thanks

Roy

Altair Forum User

Hi Roy,

When creating rigid elements we will create a component collector with no card image. But the part which you are making rigid will have a card image, material and property. FOr that part you can create an output block.

If the contact energy is high, you should check the contact parameters defined for all the contacts. Please check for any penetrations in the model.

The possible workarounds for high contact energy are:

•Check material parameters (young modulus, thickness)

•Set recommended parameter for the contact definition (Please see page 155 of RADIOSS crash ebook for recommended parameters)

•Set “physical” contact interface gap value