Page 248 - Air and gas Drilling Field Guide 3rd Edition

9.4 Nonfriction and Friction Illustrative Examples 239

1.0

0.8

(Y L /y) 0.6

0.4

0.2

0
10 –7 10 –6 10 –5 10 –4 10 –3 10 –2
N (CN ) P 0.1
VL
L
0.575
N VG N D P a
P 0:1
FIGURE 9-8. (y L /c) versus the nondimensional group [5].
N vL ðCN L Þ
N 0:575 N D P a
vG
The third empirical correlation chart is given in Figure 9-9 [5]. Guo and co-
workers [19] found that Figure 9-9 can be represented by the following correla-
tion equation:
4
2
3
c ¼ 0:91163 4:82176X 3 þ 1232:25X 22253:6X þ 116174:3X ; (9-18)
3 3 3
2.0

1.8

1.6
ψ

1.4

1.2

1.0
0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10
(N GV N L .0380 )/N 2.14
D

N GV N 0:380
FIGURE 9-9. c versus nondimensional group L [5].
N 2:14
D