MPoint Modeling • Problem Solving with MPoint

Problem Solving with MPoint

This section provides guidance for solving engineering problems with MPoint2D and MPoint3D. The modeling process is organized as a sequence from project planning through interpretation and project completion.

A typical MPoint project is developed in the following order:

1. Approach and Project Setup.

2. Select a geometry and material-point generation workflow.

3. Identify regions and assign constitutive models.

4. Apply boundary and initial conditions.

5. Establish gravity and initial conditions.

6. Reaching Equilibrium.

7. Select solution controls.

8. Apply staged loading and sequential model changes.

9. Verify the model and interpret the results.

MPoint differs from a purely Lagrangian zone analysis because material points carry the material state while a background grid is used to solve the equations of motion. The modeler must therefore consider both the material-point resolution and the background-node spacing. In hybrid analyses, zones and material points coexist and must be coupled consistently.

• Approach and Project Setup
  • Choice of MPoint2D or MPoint3D
  • Project file organization
  • Starting a model
  • Units and parameters
  • Recommended preliminary checks
• Geometry and Material-Point Generation
  • Background grid
  • Direct material-point generation
  • Creation from zones
  • Hybrid zone–MPoint workflow
  • Selecting a workflow
• Regions, Constitutive Models, and Properties
  • Direct MPoint assignment
  • Zone-based assignment before import
  • Constitutive Model Selection
  • Recommended assignment checks
  • Material changes during staged analysis
• Boundary Conditions
  • Axis-aligned boundaries in MPoint2D
  • Axis-aligned boundaries in MPoint3D
  • Plane-strain approximation in MPoint3D
  • Horizontal and vertical loaded boundaries
  • Inclined boundaries
  • Boundary-condition checks
• Initial Conditions
  • Applying gravity
  • Gravity from a zone-derived initial state
  • Gravity for directly generated material points
  • Evaluating equilibrium
• Reaching Equilibrium
  • Convergence Measures
  • Monitoring the Solution
  • Using Damping
  • Models That Do Not Reach Equilibrium
  • Practical Equilibrium Procedure
• Solution Control
  • Fixed-cycle solution
  • Dynamic analysis
  • Physical time and histories
  • Quasi-static loading
  • Volume control and particle management
  • PIC–FLIP velocity update
  • Nodal damping
  • Transfer and damping study
  • Stopping a model
• Loading and Sequential Modeling
  • Save and restore stages
  • Excavation and removal
  • Adding material points
  • Automatic zone conversion
  • Restart checks
• Verification, Interpretation, and Project Completion
  • Model checks before production runs
  • Histories
  • Resolution studies
  • Interpretation of stress and strain
  • Project completion