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03_chap_wang.qxd 05/05/2004 12:48 pm Page 112
112 José Renato Coury et al.

 1 
 559.4 (2654321 D i )0.0906m s  ( 2 0.56 )+2 
2
3
+ )
1
η =− exp  −  2 (0.56 1 
i ) 3
   (0.302 m   
 
− (
0.64
η = 1 − exp 2905.6 D i ) , with D in meters.
i
i
If only Eq. (8) is dependent on the flow rate, the procedure applied to the other veloci-
ties is as follows:
For v = 15 m/s,
i
3
m 3600 s
3
Q = 0.139 = 500.4 m h
s 1 h
− (
0.64
η = 1 − exp 3332.2 D i ) with D in meters.
i i
For v = 20 m/s,
i
3
m 3600s
3
Q = 0.1812 = 652.3m h
s 1 h
− (
0.64
η = 1 − exp 3627.2 D i ) with D in meters.
i i
Figure 5 shows the efficiency curves obtained with the Leith and Licht model compared to the
experimental results of Dirgo and Leith (17), for the same operating conditions.
Iozia and Leith Model
For v = 10 m/s, we can start by calculating the diameter of the cyclone’s central axis [Eq.
i
(25)]:
d c = 0.47  0.151 m 0.060 m  − 0.25  0.151 m  1.4

0.302 m   ( 0.302 m) 2   0.302 m 
d = 0.096 m
c
Because d < B, Eq. (27) is utilized for the calculation of Z :
c c
Z = (1.208 m − 0.151 m )
c

Z = 1.057 m
c
The maximum tangential velocity is calculated from Eq.(28):
)(
(
v tmax = 6.1 10m s)  (  0.151 m 0.060 m)   0.61  0.151 m  − 0.74  1.208 m  − 0.33
 ( 0.302 m)   0.302 m   0.302 m 
2
v tmax = 15.8 m s

Knowing Q, Z , v , and the properties of the gas and particles, the diameter is calculated
c tmax
from Eq. (24):