The relation between surface flow rate q, bottom-hole pressure p_{wf} and field-average formation pressure p_r during the stabilised reservoir flow:
q = J \, (p_r - p_{wf}) |
corresponding to linear IPR with constant productivity index :
(1) | J = \frac{2 \pi \sigma}{ \ln \frac{r_e}{r_w} + \epsilon+ S} |
where
\sigma | transmissibility above bubble point |
\epsilon = 0.5 | for Steady State (SS) well flow regime |
\epsilon = 0.75 | for Pseudo Steady State (PSS) well flow regime |
See also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Well Testing / Pressure Testing
Reference
Dupuit, J., Etudes theoriques et pratiques sur le mouvement des eaux dans les canaux decouverts et a travers les terrains permeables, 2eme edition; Dunot, Paris, 1863.