Page 512 - Air and Gas Drilling Manual

The foam quality as it exits this cased annulus section is
sfa2 Q ga2 Chapter 10: Stable Foam drilling 10-37
Q ga2 Q w
0 789
.
sfa2
.
.
0 789 0 234
0 771
.
sfa2
Using Equation 10-5, the absolute viscosity of the foam as it exits this cased
annulus section is
.
0 00002089 1 3 6 0 771)
.
(
.
sfa2
lb sec
.
0 00007890
sfa2 2
ft
The specific weight of the foam as it exits this cased annulus section is
approximated by
w ˙ g w ˙ w
sfa2
P at T av2
Q g Q w
P a1 T at
.
1 821 14 60
.
sfa2
,
1 826 6 . 572 66
.
.
( 27 64) 0 234
.
.
70 502 519 67
,
3
.
16 049 lb/ft
sfa2
Using Equation 1-2, the density of the foam as it exits this cased annulus is
16 049
.
sfa2
.
32 2
lb sec 2
.
0 498
sfa2 4
ft