[MPM] Assistance with Inhomogeneous Dirichlet Boundary Conditions in Kratos MPM

[duribes]

Dear all,

I am working on a tensile test simulation using the Material Point Method (MPM) and preprocessing the input files with GiD 17.1.1d. In the attached figure (Geometry_BC_Tensile.pdf), you can see the geometry and boundary conditions for my problem.

I aim to simulate the tensile test evolution across multiple time steps, but I am unsure how to impose the inhomogeneous Dirichlet boundary condition at the top of the body (i.e., the prescribed displacement). From my research, I understand that methods like the Lagrange multiplier or penalty augmentation could achieve this (e.g., Lagrange multiplier imposition of non-conforming essential boundary conditions in implicit material point method, Nonconforming Dirichlet boundary conditions in implicit material point method by means of penalty augmentation).

To assist in understanding my setup, I have also attached the GiD project files (tensile.gid). Additionally, I am using VTK files as output to visualize the results. My ultimate goal is to extend this knowledge to simulate a metal cutting process.

I would greatly appreciate:

• Guidance on imposing inhomogeneous Dirichlet boundary conditions in the Kratos MPM application.
• Examples or references on using Lagrange multipliers or penalty methods in this context.

Thank you in advance for your support!

Best regards,
Diego Uribe

Geometry_BC_Tensile.pdf
tensile.gid.zip