Element selection for soft tissue in marc

Hello Rahul,

Greetings of the day.

When simulating soft tissue behavior involving large deformation and incompressibility in Marc Mentat, choosing appropriate elements is essential.
For 3D simulations, the 20-node brick element (Type 21) is highly effective as it offers accurate strain representation using triquadratic interpolation functions and relies on 27-point Gaussian integration for stiffness calculations.

For modeling small-strain incompressible elasticity with Mooney-Rivlin or Ogden material models, element types 35 or 61 are recommended. These elements incorporate specialized formulations to manage incompressibility, with Type 35 utilizing the Herrmann variational principle.

Element Type 57 is versatile and suitable for general constitutive relations, employing reduced integration. However, care should be taken to address potential hourglass modes. Type 7 is particularly adept in scenarios involving contact analysis. For materials exhibiting time-dependent properties such as viscoelasticity or creep, MSC Marc offers robust tools, although it does not support dynamic variation of fiber orientations.

For more detailed instructions, refer to the VOL B Element Library section within the MARC documentation.

I hope this helps.

Regards,

Amol Kumbhar

Hello Rahul,

Greetings of the day.

When simulating soft tissue behavior involving large deformation and incompressibility in Marc Mentat, choosing appropriate elements is essential.
For 3D simulations, the 20-node brick element (Type 21) is highly effective as it offers accurate strain representation using triquadratic interpolation functions and relies on 27-point Gaussian integration for stiffness calculations.

For modeling small-strain incompressible elasticity with Mooney-Rivlin or Ogden material models, element types 35 or 61 are recommended. These elements incorporate specialized formulations to manage incompressibility, with Type 35 utilizing the Herrmann variational principle.

Element Type 57 is versatile and suitable for general constitutive relations, employing reduced integration. However, care should be taken to address potential hourglass modes. Type 7 is particularly adept in scenarios involving contact analysis. For materials exhibiting time-dependent properties such as viscoelasticity or creep, MSC Marc offers robust tools, although it does not support dynamic variation of fiber orientations.

For more detailed instructions, refer to the VOL B Element Library section within the MARC documentation.

I hope this helps.

Regards,

Amol Kumbhar