Particle Breakage
Breakage of particles is described using the fragmentation equation. The continuous fragmentation equation on a volume basis is written as (Ref. 7)
(3-182)
The first right-hand side term describes the source (or birth) of new particles as larger particles with a volume from v to infinity break into two or more smaller particles including one with a volume of v. The second term, the sink (or death), describes the loss of particles with the volume v due to breakage. Rewritten on a size basis Equation 3-182 becomes
(3-183)
Here, S is a selection function and b is a probability density function. Note that these functions are a function of volume in Equation 3-182 but a function of size in Equation 3-183. The discretized formulation is written as (Ref. 7)
(3-184)
where the birth weight term is written as
(3-185)
death weight term is written as
(3-186)
and where
(3-187)
The selection and probability density function are implemented as (Ref. 7)
(3-188)
and
(3-189)
where S0 is a constant controlling the breakage rate and γ is the average number of resulting particles from the breakage of a larger particle.