Difference between revisions of "JD"

Revision as of 16:38, 11 August 2018

JD - dimensionless productivity index, inverse of dimensionless pressure (based on average pressure) ^[1].

From the Darcy's law for an unfractured well located in the center of a circular drainage area, the JD in pseudo-steady state is as follows:

{J_D} = \frac{1}{ln{\frac{r_e}{r_w}-\frac{3}{4}+S}}

Oil

{J_D} = \frac{141.2 B \mu}{kh} \frac{q}{\bar{P} - P_{wf}}

Gas

J_D=\frac{1422 \times 10^3\ T_R}{kh} \frac{q_g}{P_{\bar{P}}-P_{P_{wf}}}

B

= formation volume factor, bbl/stb

kh

= permeability times thickness, md*ft

\bar{P}

= average reservoir pressure, psia

P_{wf}

= well flowing pressure, psia

r_w

= wellbore radius, ft

r_e

= drainage radius, ft

S

= skin factor, dimensionless

↑ Rueda, J.I.; Mach, J.; Wolcott, D. (2004). "Pushing Fracturing Limits to Maximize Producibility in Turbidite Formations in Russia" (SPE-91760-MS). Society of Petroleum Engineers.

@@ Line 22: / Line 22: @@
 :<math> r_w </math> = wellbore radius, ft
 :<math> r_e </math> = drainage radius, ft
+:<math> S </math> = skin factor, dimensionless
 == References ==