dem_atom_insert

DEM particle insertion for MDDEM. Randomly places particles in the simulation domain with overlap checking, and automatically computes a stable timestep from the Rayleigh wave period.

Features

• Random placement within the domain or a specified sub-region
• Overlap checking (1.1x radius buffer) to prevent initial interpenetration
• Optional random velocity (Gaussian per component) and/or directional velocity
• Multiple insert blocks with different materials, counts, radii, densities, and velocities
• Automatic timestep calculation: dt = 0.15 * min(Rayleigh period) across all particles

Configuration

[[particles.insert]]
material = "glass"
count = 500
radius = 0.001
density = 2500.0
velocity = 0.5              # Random RMS velocity (Gaussian, optional)
velocity_x = 0.0            # Directional velocity (additive with random, optional)
velocity_y = 0.0
velocity_z = -1.0
region_x_low = 0.005        # Insertion sub-region (optional, defaults to domain)
region_x_high = 0.020

Usage

DemAtomInsertPlugin is included in GranularDefaultPlugins. It runs at setup time on rank 0, populating both Atom and DemAtom fields.

Part of the MDDEM workspace.