MPoint Modeling • MPoint Modeling

MPoint Modeling

Note

Material in the underlying sections applies to MPoint2D and MPoint3D unless otherwise stated. The fundamental Material Point Method formulation and modeling workflow are shared between the two programs. However, MPoint2D operates under two-dimensional assumptions, while MPoint3D provides a fully three-dimensional formulation. Topics, commands, examples, or numerical considerations that are specific to either program are explicitly identified where applicable.

This section introduces MPoint and provides an overview of the fundamental concepts and procedures involved in constructing and solving Material Point Method models. Many of the topics introduced here are described in greater detail in later parts of the Help. Particular emphasis is placed on the representation of material using material points, the use of a computational background grid, the transfer of information between material points and grid nodes, and the treatment of large deformation and material motion.

The section is divided into two major parts.

This section provides a first look at MPoint2D and MPoint3D, including their purpose, fundamental numerical concepts, modeling environment, principal capabilities, and common fields of application. It also introduces the relationship between the Lagrangian material-point representation and the Eulerian-style computational background grid used during the solution process.

MPoint Tutorials

These sections are intended for users who want to begin constructing and running models directly. The tutorials provide step-by-step guidance on the principal tasks involved in creating MPoint2D and MPoint3D models, including model initialization, geometry preparation, material-point generation, background-grid definition, constitutive-model assignment, boundary conditions, loading, solution control, and interpretation of results.

This section provides a detailed discussion of the sequential modeling methodology used to construct and solve an MPoint model. It describes the recommended progression from geometry and material definition through initial-state preparation, material-point generation, grid construction, boundary-condition assignment, solution control, and result interpretation.

Particular attention is given to the selection of material-point density and background-grid spacing, initialization of stress and state variables, quasi-static and dynamic solution procedures, numerical damping, time-step selection, particle-grid transfer, and the treatment of large deformation.

With regard to the sections following this one (MPoint Modeling), their contents may be summarized briefly as follows:

MPoint Theory and Background - provides background information and descriptions of the theoretical basis of the Material Point Method formulations implemented in MPoint2D and MPoint3D. Topics include the governing equations, material-point discretization, background-grid calculations, particle-to-grid and grid-to-particle transfer, strain and stress updates, constitutive integration, time integration, and numerical stability considerations.

Examples - provides access to example applications, verification problems, benchmark simulations, and other examples appearing throughout the Help documentation. The examples demonstrate both fundamental MPM behavior and practical applications involving large deformation, failure, flow, impact, contact, and coupled modeling workflows.

In addition to the aforementioned sections, which form the portion of the documentation specific to MPoint, several major sections of the Help system contain information applicable across the broader software framework.

Program Guide > Program Mechanics - provides an overview of the general methods used to conduct a modeling project in the program. This section contains most of the user-interface documentation and describes project organization, model execution, data inspection, plotting, file management, and other common program operations.

Scripting - provides complete reference documentation for using FISH and Python to perform scripted operations within a model. Scripting may be used to automate model generation, control solution sequences, modify material properties, define loading histories, process material-point data, perform parameter studies, and develop customized analysis procedures.