Difference between revisions of "BHP from the fluid level"

Revision as of 12:04, 27 April 2020

BHP from the fluid level notations

Fluid level is the interface between the gas and liquid phases occurred in the annulus of the well.

Echometer is used to measure the fluid level in the wells.

Fluid level is used to calculate and monitor the bottom hole pressure of the wells.

The physics is based on the principal hydrostatics law:

P=\frac{\rho g h}{101325}

When the well is flowing with the pump this is how fluids segregate in the well bore:

Oil, gas and water are produced through the tubing from the reservoir to the surface
Gas is in the annulus from the surface to fluid level, Hd
Oil and gas are between the fluid level Hd, and the pump setting depth, Hd
Water, oil and gas are between pump and the top of the perforations, Hperfs
Water is in the rathole

P_{wf}=P_{ann}+\frac{(H_{perfs}-H_{pump})(SG_o(1-WCUT)+SG_w WCUT)+(H_{pump}-H_d)SG_o}{10.32}

Note that for the deviated wells TVD depths should be used.

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

@@ Line 25: / Line 25: @@
 :<math>P_{wf}=P_{ann}+\frac{(H_{perfs}-H_{pump})(SG_o(1-WCUT)+SG_w WCUT)+(H_{pump}-H_d)SG_o}{10.32}</math>
-Note that for a deviated wells TVD depth should be used.
+Note that for the deviated wells TVD depths should be used.
 ==Nomenclature==