Difference between revisions of "Gilbert choke equation"

Revision as of 18:43, 8 November 2024

The most common formula used for multiphase flow through surface chokes by Gilbert ^[1]^[2].

Gilbert developed his equation from field data in California.

P_{wh}=\frac{435 \times GLR^{0.546}}{D^{1.89}} \times q

Note that the equation is independent of the downstream pressure and assumes that the downstream pressure is less than 70% of the upstream pressure.

Oil rate = 600 bbl/d, GLR=400 scf/bbl, D=22/64 in, Line pressure = 180 psi

Calculate well head pressure?

P_{wh}=\frac{435 \times 0.4^{0.546}}{22^{1.89}} \times 600 = 460 psia

Check validity 180/460=0.4 - OK

g

= 9.81, m/s^2

h

= depth, m

H_d

= fluid level, m

H_{perfs}

= top of the perforations, m

H_{pump}

= pump setting depth, m

P

= pressure, atm

P_{ann}

= annulus presssure, atm

P_{wf}

= well flowing bottomhole pressure, atm

\rho

= density, kg/m^3

SG_o

= oil specific gravity, dimensionless

SG_w

= water specific gravity, dimensionless

WCUT

= well water cut, fraction

↑ Gilbert, W.E. (1954). Flowing and Gas-Lift Well Performance. Drilling and Production Practice API. p. 143.
↑ Brown, Kermit (1984). The Technology of Artificial Lift Methods. Volume 4. Production Optimization of Oil and Gas Wells by Nodal System Analysis. Tulsa, Oklahoma: PennWellBookss.

@@ Line 12: / Line 12: @@
 ==Example==
 ===Given data===
-Oil rate = 600 bbl/d, GLR=400 scf/bbl, D=22/64, Line pressure = 180 psi
+Oil rate = 600 bbl/d, GLR=400 scf/bbl, D=22/64 in, Line pressure = 180 psi
 Calculate well head pressure?