Page 454 - Air and Gas Drilling Manual

9-58 Air and Gas Drilling Manual
Using Equation 1-2, the density of the gas as it enters this drill string section,
is
.
gi4 17 96 gi4 ,
32 2
.
lb sec 2
0 558
.
gi4 4
ft
From Equation 9-7, the kinematic viscosity of the gas at this location, gi4 , is
0 000000251
.
gi4
0 558
.
ft 2
0 000000449
.
gi4
sec
The average kinematic viscosity of the mixture as it enters this drill string section,
, is
avi4
0 0002691)
.
1 282)( .
( . 0 000000449) ( 31 92)( .
avi4
1 282 31 92
.
.
2
.
0 000259 ft /sec
avi4
Using the inside diameter of the drill pipe tool joints, D 6, the approximate
average velocity of the aerated drilling fluid as it enters this drill string section, V i4,
is
.
1 826 6 . 598 79
,
19 47)
(. 0 426
.
,
.
573 888 519 67
V i4
0 292 2
.
4
V i4 744 ft/sec
.
Using Equation 6-83, the Reynolds number of the aerated drilling fluid as it
enters this drill string section, N Ri4, is
7
0
(.44 ) ( .292 )
N
Ri4
. 0 000259
N Ri4 8 386
,