ParticleInteraction

defines the dynamics of particle-particle interaction within the DROPLETPHASE as material property

Originally, the particles within DROPLETPHASE were not interacting at all. An interaction between particles within a DROPLETPHASE chamber may now be enabled by defining:

ParticleInteraction($Material$) = (k_n, e_n, E_a, R_a, mu)

The interaction is resolved by a DEM approach which calculates forces on the basis of virtual overlap and relative velocity of the droplets. See DropletCollisions

Parameter	Meaning	Possible Values	Default
k_n	Spring Constant for particle interaction	k_n >= 0.0	0.0 (no collision modeling)
e_n	if 0 <= e_n <= 1 Coefficient of Restitution (0 ideal plastic, 1.0 ideal elastic), if e_n < 0, negative value of the damping coefficient	between 0 and 1 or negative	0.0
E_a	Adhesive potential difference relative to the particle mass	non-negative	0.0 (no adhesion)
R_a	Broadness of zone of attraction relative to d30	non-negative	1.0
mu	Friction Coefficient	non-negative	0.0 (off)

Example:

ParticleInteraction($Material$) = (1.0, .1, 1e-3, 1.0, 0.0)

specifies that the particles of material $Material$ within a DROPLETPHASE chamber interact with each other. For the collision a spring constant of size 1.0 is specified, a coefficient of restitution of 0.1 means that 90% of the kinetic energy is dissipated by the colliding particles. Additionally, an adhesive potential is given acting within a close range of the particles, attracting each other.