ABSTRACT
The concentration of particles suspended in gas or liquid is expressed in several ways. The various definitions of particle concentration are summarized as follows:
1. Mass flow ratio m (–):
m WQ
(3.1)
where W and Q are the mass flow rates of particles and fluid, respectively. 2. Flow concentration c (kg/m3):
c WQ m v a
r
(3.2)
where Qv is the volumetric fluid flow rate and ra the density of fluid. If the concentration c is divided by the particle density rp, it becomes dimensionless and is called the volumetric concentration. 3. Holdup concentration ch (kg/m3):
c dwV
Wdl V
W Ah n n
(3.3)
where dw is the mass of suspension, V the volume occupied by the suspension, dl the length, v the mean velocity of particles, and A the cross section.
