76 CHEMICAL ENGINEERING VOLUME 1 SOLUTIONS
Fraction of pipe occupied by slurry slugs is
1
RC 1
Assuming that the pressure drop is the sum of the pressure drops along the slugs, then:
the new pressure drop is:KfRC 1 ugn
(
l
RC 1
)
DKunlRC 1 n^1
Then: rD
pressure gradient with air
pressure gradient without air
D
KunlRC 1 n^1
Kunl
DRC 1 n^1
For nD 0 .15 and:RD 1
rD 2 ^0.^85 D 0. 55