:: Section 7
From the above, we can see that the collection efficiency of a cyclone depends
on the competition of two movements: (1) the movement following the circular
path of the gas stream; and (2) the outward movement toward the cyclone
wall due to centrifugal force (which is perpendicular to the gas stream).
The dust collection (due to impaction) occurs if a particle hits the wall
before it leaves the system (i.e. before reaching the vortex core). There
are two theories developed for the predicting of the collection efficiency
of a cyclone, depending upon the model of gas flow in a cyclone. For detailed
derivation of the theories, refer to the following references:
- "Fundamentals of Air Quality Systems: Design of Air Pollution
Control Devices", by K. E. Noll, American Academy of Environmental
- "Air Pollution Control: A Design Approach" by C. D. Cooper
and F. C. Alley, Waveland Press.
- "Air Pollution Control Equipment" by L. Theodore and A.J. Buonicore., CRC Press.
- "The Collection Efficiency of Cyclone Type Particle Collectors - A New Theoretical Approach" by D. Leith and W. Licht, American Institute of Chemical Engineers (AIChE) Symposium Series# 126, Vol. 68, 196-206 (1972)
Only the major equations are summarized in the following sections.