Difference between revisions of "Griffith correlation"

Revision as of 16:58, 27 March 2017

The Griffith correlation ^[1] is an empirical correlation which defines:

The bubble flow exist when:

\frac{v_g}{v_g + v_L} < L_B

^[3]

L_B = 1.071 - 0.2218 \frac{(v_g+v_L)^2}{D}

, with the limit

L_B \geqslant 0.13

^[2]

The gas holdup:

H_g = \frac{1}{2}\ \left ( 1 + \frac{v_g+v_L}{v_s} - \sqrt{ \left ( 1 + \frac{v_g+v_L}{v_s} \right )^2 - 4 \frac{v_g}{v_s}} \right )

^[2]

H_g

= gas holdup factor, dimensionless

L_B

= bubble-slug boundary, dimensionless

v

= velocity, ft/sec

v_s

= 0.8, slip velocity (difference between average gas and liquid velocities), ft/sec

g = gas
L = liquid
SL = superficial liquid
SG = superficial gas

↑ Griffith, P.; Wallis, G. B. (August 1961). "Two-Phase Slug Flow". Journal of Heat Transfer. ASME. 83: 307–320.
↑ ^2.0 ^2.1 ^2.2 ^2.3 Orkiszewski, J. (June 1967). "Predicting Two-Phase Pressure Drops in Vertical Pipe". Journal of Petroleum Technology. SPE. 19 (SPE-1546-PA).
↑ Economides, M.J.; Hill, A.D.; Economides, C.E.; Zhu, D. (2013). Petroleum Production Systems (2 ed.). Westford, Massachusetts: Prentice Hall. ISBN 978-0-13-703158-0.

@@ Line 19: / Line 19: @@
 :<math> H_g </math> = gas holdup factor, dimensionless
-:<math> f </math> = friction factor, dimensionless
-:<math> GLR </math> = gas-liquid ratio, scf/bbl
 :<math> L_B </math> = bubble-slug boundary, dimensionless
-:<math> M </math> = total mass of oil, water and gas associated with 1 bbl of liquid flowing into and out of the flow string, lb<sub>m</sub>/bbl
-:<math> N_D </math> = pipe diameter number number, dimensionless
-:<math> N_GV </math> = gas velocity number, dimensionless
-:<math> N_L </math> = liquid viscosity number, dimensionless
-:<math> N_LV </math> = liquid velocity number, dimensionless
-:<math> p </math> = pressure, psia
-:<math> q_c </math> = conversion constant equal to 32.174, lb<sub>m</sub>ft / lb<sub>f</sub>sec<sup>2</sup>
-:<math> q_L </math> = total liquid production rate, bbl/d
-:<math> Re </math> = Reynolds number, dimensionless
-:<math> R_s </math> = solution gas-oil ratio, scf/stb
-:<math> SG </math> = specific gravity, dimensionless
-:<math> T </math> = temperature, °R or °K, follow the subscript
 :<math> v </math> = velocity, ft/sec
-:<math> WOR </math> = water-oil ratio, bbl/bbl
+:<math> v_s </math> = 0.8, slip velocity (difference between average gas and liquid velocities), ft/sec
-:<math> z </math> = gas compressibility factor, dimensionless
+===Subscripts===
+g = gas<BR/>
+L = liquid<BR/>
+SL = superficial liquid<BR/>
+SG = superficial gas<BR/>
 == References ==