Except for a constant 2p, the Leung number is essentially the
square root of the ratio of the feed rate Q to the clarification rate
by centrifugal sedimentation vsAp. From Eq. (22), the Leung number
is a combination of four dimensionless p groups (Ro, Re, Lc/
Rp, x50/Rp). This is somewhat analogous to the Raleigh number used
in natural convection, wherein Ra ¼ GrPr ¼ ðDq=qÞRe2Pr. Thus, Ra
is also a combination of three dimensionless p groups - the density
difference ratio, Reynolds number, and the Prandtl number, Pr.