fundamentals of engineering supplied-reference handbook - Ventech!

Cyclone
Cyclone Collection (Particle Removal) Efficiency
1
1+
η =
, where
( ) 2
d
pc p d
dpc = diameter of particle collected with 50% efficiency,
dp = diameter of particle of interest, and
η = fractional particle collection efficiency.
e
146
Cyclone Efficiency (%)
Cyclone Ratio of Dimensions to Body Diameter
ENVIRONMENTAL ENGINEERING (continued)
Cyclone Effective Number of Turns Approximation
1 ⎡ Lc
⎤
N e = ⎢Lb
+ ⎥ , where
H ⎣ 2 ⎦
Ne = number of effective turns gas makes in cyclone,
H = inlet height of cyclone (m),
Lb = length of body cyclone (m), and
= length of cone of cyclone (m).
Lc
Cyclone 50% Collection Efficiency for Particle Diameter
d
pc
⎡
9µ
W
⎤
= ⎢ ⎥
⎢ 2πNV
e i( ρp −ρg)
⎥
⎣ ⎦
0.5
, where
dpc = diameter of particle that is collected with 50%
efficiency (m),
µ = viscosity of gas (kg/m•s),
W = inlet width of cyclone (m),
Ne = number of effective turns gas makes in cyclone,
Vi = inlet velocity into cyclone (m/s),
ρp = density of particle (kg/m 3 ), and
= density of gas (kg/m 3 ).
ρg
Cyclone Collection Efficiency
Particle Size Ratio
Dimension High Efficiency Conventional High Throughput
Inlet height H 0.44 0.50 0.80
Inlet width W 0.21 0.25 0.35
Body length Lb 1.40 1.75 1.70
Cone length Lc 2.50 2.00 2.00
Vortex finder length S 0.50 0.60 0.85
Gas exit diameter De 0.40 0.50 0.75
Dust outlet diameter Dd 0.40 0.40 0.40
d
d
p
pc