Study on the Separation Technology of HGS and Its Effect
157
g
acceleration of gravity, m/s 2
HGS abbreviation of the hollow glass sphere
H
convective heat transfer coefficient, W/(m 2 ·°C)
P
pressure in the annulus, Pa
Q
flow rate, m 3 /s
q
rate of mass transfer, m 3 /s
s
perimeter of section, mm
S cp
friction heat source of the drilling fluid inside the drill string, W/m 3
S ca
friction heat source of the drilling fluid in the annulus, W/m 3
T
drilling fluid temperature, °C
t
step of time, s
z
step of space in axial, m
λ p
heat conductivity coefficient, W/(m·°C)
ρ
fluid density, kg/m 3
v
flow rate of drilling fluid, m/s
ε
separation efficiency, %
α
volume fraction, %
Subscript
m drilling fluid
a
in annulus
p
the drill string
u
the upper part of the zone
d
the lower part of the zone
mi mixed fluid
*
the variable changes the symbol as the region varies
hgs hollow glass sphere
Pi the wall inside the drill string
p o the wall outside the drill string
w
the wall of the wellbore
References
1. Ziegler, R., Ashley, P.: Successful application of deep water dual gradient drilling. In: Presented at the IADC/SPE managed pressure drilling and underbalanced operation conference
and exhibition held in San Antonio, Texas, USA, April 17–18 2013 (2013)
2. Deng, S., Fan, H., Tian, D., Liu, Y., Zhou, Y., Wen, Z., Ren, W.: Calculation and application
of safe mud density window in deep-water shallow layers, Offshore Technology Conference
(2016)
3. Stave, R.: Implementation of dual gradient drilling. In: Presented at the offshore technology
conference held in Houston, Texas, USA, 5–8 May 2014 (2014)
4. Halkyard. J.: Hollow glass microspheres: an option for dual gradient drilling and deep ocean
mining lift. In: Presented at the offshore technology conference Asia held in Kuala Lumpur,
Malaysia, 25–28 March 2014 (2014)
157
g
acceleration of gravity, m/s 2
HGS abbreviation of the hollow glass sphere
H
convective heat transfer coefficient, W/(m 2 ·°C)
P
pressure in the annulus, Pa
Q
flow rate, m 3 /s
q
rate of mass transfer, m 3 /s
s
perimeter of section, mm
S cp
friction heat source of the drilling fluid inside the drill string, W/m 3
S ca
friction heat source of the drilling fluid in the annulus, W/m 3
T
drilling fluid temperature, °C
t
step of time, s
z
step of space in axial, m
λ p
heat conductivity coefficient, W/(m·°C)
ρ
fluid density, kg/m 3
v
flow rate of drilling fluid, m/s
ε
separation efficiency, %
α
volume fraction, %
Subscript
m drilling fluid
a
in annulus
p
the drill string
u
the upper part of the zone
d
the lower part of the zone
mi mixed fluid
*
the variable changes the symbol as the region varies
hgs hollow glass sphere
Pi the wall inside the drill string
p o the wall outside the drill string
w
the wall of the wellbore
References
1. Ziegler, R., Ashley, P.: Successful application of deep water dual gradient drilling. In: Presented at the IADC/SPE managed pressure drilling and underbalanced operation conference
and exhibition held in San Antonio, Texas, USA, April 17–18 2013 (2013)
2. Deng, S., Fan, H., Tian, D., Liu, Y., Zhou, Y., Wen, Z., Ren, W.: Calculation and application
of safe mud density window in deep-water shallow layers, Offshore Technology Conference
(2016)
3. Stave, R.: Implementation of dual gradient drilling. In: Presented at the offshore technology
conference held in Houston, Texas, USA, 5–8 May 2014 (2014)
4. Halkyard. J.: Hollow glass microspheres: an option for dual gradient drilling and deep ocean
mining lift. In: Presented at the offshore technology conference Asia held in Kuala Lumpur,
Malaysia, 25–28 March 2014 (2014)