MATERIAL LAW51 IN RADIOSS

James Lewis
James Lewis Altair Community Member
edited September 2022 in Community Q&A

Hi experts,

 

I'm doing explosive tutorials, and wondering one thing that:

When define parameter for TNT materials here

image

Why we have to enter parameter for Air and Copper material, even the volume fraction equal 0.

image

 

Anyone have experience with type of material, please give me some information.

Here the tutorial link: 

https://2022.help.altair.com/2022.1/hwsolvers/rad/topics/solvers/rad/euler_formulation_example_r.htm#euler_formulation_example_r

 

Many thanks!

 

Best Answer

  • Mathis
    Mathis
    Altair Employee
    edited September 2022 Answer ✓

    Hi James, 

    Law51 is a multi-material law. It means that a cell has the possibility at any time to contain some amout of each sub-material. So Radioss needs to have the information of each sub-material possible. 

    Law51 has recently been updated with a new formulation Iform=12 which is much more userfriendly. I strongly recommand you to use it. 

    I attach you a 2D axisymmetrical cylinder test model with LAW51 - Iform=12 formulation. I hope it will be helpful or you. 

    Regards,

    Mathis

Answers

  • Mathis
    Mathis
    Altair Employee
    edited September 2022 Answer ✓

    Hi James, 

    Law51 is a multi-material law. It means that a cell has the possibility at any time to contain some amout of each sub-material. So Radioss needs to have the information of each sub-material possible. 

    Law51 has recently been updated with a new formulation Iform=12 which is much more userfriendly. I strongly recommand you to use it. 

    I attach you a 2D axisymmetrical cylinder test model with LAW51 - Iform=12 formulation. I hope it will be helpful or you. 

    Regards,

    Mathis

  • James Lewis
    James Lewis Altair Community Member
    edited September 2022

    Hi James, 

    Law51 is a multi-material law. It means that a cell has the possibility at any time to contain some amout of each sub-material. So Radioss needs to have the information of each sub-material possible. 

    Law51 has recently been updated with a new formulation Iform=12 which is much more userfriendly. I strongly recommand you to use it. 

    I attach you a 2D axisymmetrical cylinder test model with LAW51 - Iform=12 formulation. I hope it will be helpful or you. 

    Regards,

    Mathis

    Hi Mathis,

     

    Your answer exactly solved my difficulty.

    Thanks very much!

     
  • James Lewis
    James Lewis Altair Community Member
    edited September 2022

    Hi James, 

    Law51 is a multi-material law. It means that a cell has the possibility at any time to contain some amout of each sub-material. So Radioss needs to have the information of each sub-material possible. 

    Law51 has recently been updated with a new formulation Iform=12 which is much more userfriendly. I strongly recommand you to use it. 

    I attach you a 2D axisymmetrical cylinder test model with LAW51 - Iform=12 formulation. I hope it will be helpful or you. 

    Regards,

    Mathis

    By the way, could you mind to explain to me the purpose of Polynomial and JWL equation of state in Radioss?

    Thanks!

     

     
  • James Lewis
    James Lewis Altair Community Member
    edited September 2022

    Hi James, 

    Law51 is a multi-material law. It means that a cell has the possibility at any time to contain some amout of each sub-material. So Radioss needs to have the information of each sub-material possible. 

    Law51 has recently been updated with a new formulation Iform=12 which is much more userfriendly. I strongly recommand you to use it. 

    I attach you a 2D axisymmetrical cylinder test model with LAW51 - Iform=12 formulation. I hope it will be helpful or you. 

    Regards,

    Mathis

    Hi Mathis,

     

    Why we have to enter double parameter for copper here.

    image

     
  • Mathis
    Mathis
    Altair Employee
    edited September 2022

    By the way, could you mind to explain to me the purpose of Polynomial and JWL equation of state in Radioss?

    Thanks!

     

     

    image

  • Mathis
    Mathis
    Altair Employee
    edited September 2022

    image

    Hi James,

    Please look at the slide up. I hope it answer to your question. 

    Regards,

    Mathis

  • Mathis
    Mathis
    Altair Employee
    edited September 2022

    Hi Mathis,

     

    Why we have to enter double parameter for copper here.

    image

     

    Hi James,

    It is not really necessary. It is just that as law51 has up to 4 sub-material, I like to put all of them just in case. Again, purely optional ;)

    Regards,

    Mathis

  • James Lewis
    James Lewis Altair Community Member
    edited September 2022

    Hi James,

    It is not really necessary. It is just that as law51 has up to 4 sub-material, I like to put all of them just in case. Again, purely optional ;)

    Regards,

    Mathis

    Hi Mathis,

     

    I got it, thank you very much!