insertion mode pack command

Purpose

insertion mode pack is used to generate a pack of particles inside a region (examples).

Note

This command is supported by Aspherix GPU.

Syntax

insertion mode pack keyword value

General insertion keywords are documented here. This document only describes the specific keywords for the insertion of a pack of particles.

Return to the insertion documentation.

Keywords

Description

region

obligatory, ID of the region where the particles will be generated

target_mass *
desired mass to insert
range: (0,∞); units: [mass]

target_volume_fraction *
desired volume fraction for the region
range: (0,1); units: [-]

target_particle_count_in_region *
desired number of particles in the region
range: [1,∞); units: [-]

target_particle_count *
desired number of particles to be inserted each time
range: [1,∞); units: [-]

check_distance_from_subdomain_border
yes or no or maximum_radius or bounding_sphere or bounding_box, allows
to change distance to subdomain border for the insertion of nonspherical particles
default: yes (= bounding_box)

fiber_insert
yes or no; reduces distance to subdomain border from bounding box / sphere
to sphere radius for fibers and multispheres
default: no

monte_carlo_steps
number of Monte-Carlo steps for calculating the region’s volume
default: 100000; range: [1,∞); units: [-]

* These four keywords are mutually exclusive.

Examples

insertion id ins mode pack particle_distribution pdd1 velocity constant (0, 0, -0.2) &
     region bc target_particle_count_in_region 250

insertion id ins mode pack particle_distribution pdd1 velocity constant (0, 0, -0.3) &
     insert_every_time 0.05 target_mass 0.25 region insertion_region

insertion id ins mode pack particle_distribution pdd1 check_overlap optimized &
     packing_generator style batch batch_size 200 velocity constant (0, 0, -0.3) &
     insert_every_time once target_volume_fraction 0.25 region insertion_region

insertion mode pack region base_reg insert_every_time once target_particle_count 500 &
     fiber_insert yes particle_distribution p2 velocity constant ( 0, 0, 0.1 ) id i1 all_in no

insertion mode pack region insertion_region target_mass 10 particle_distribution pdd1 &
     velocity constant ( 0.5, 0, -1) check_distance_from_subdomain_border maximum_radius &
     monte_carlo_steps 10000

Description

This command offers four different criteria for the choice of the inserted material amount. The keyword target_mass defines the total mass of particles in the insertion region, including the mass already present prior to the insertion. If the already present particle mass exceeds the given target_mass, no more particles are inserted.

With the target_volume_fraction keyword, the target volume fraction is defined.

The target_particle_count_in_region keyword can be used to define the desired total amount of particles in the insertion region. Just as for the target_mass command, also the particles present prior to the insertion are considered, and no further particles are inserted if the total number of particles exceeds the given value. In contrast to this, the target_particle_count keyword ignores the already present particles and tries to insert the full number of particles given by the keyword.

The number of particles always applies to the number of particle templates / particle conglomerates for composed particles such as multispheres, fibers or concave triangulated particles.

If neither of the quantities is defined, a case-dependent default particle rate is inserted.

If the general insertion keyword check_overlap is set to yes (default), optimized or legacy, then check_distance_from_subdomain_border keyword can be used to control the insertion distance of particles from processor domain borders. Valid options are maximum_radius (of a single sphere within a multisphere particle), bounding_radius (of the whole particle, the default if check_overlap = legacy), or bounding_box (only valid and the default if check_overlap = optimized).

For fiber particles the fiber_insert keyword in mode yes can be used to reduce the distance to the subdomain to the sub-sphere radius and avoid gaps at processor boundaries when inserting vertical fibers (e.g., grass).

The monte_carlo_steps keyword is used to control the number of Monte-Carlo tries that are used for the volume calculation.