(1) | J = \frac{q}{|p_e - p_{wf}|} |
where
q | flowrate (the specification of which may differ, see below) |
p_e | formation pressure |
p_{wf} | bottom hole pressure at sandface |
The definition of flowrate q and formation pressure p_e may vary depending on application.
Overall concept is applicable to both producers and injectors but can be split into specific definitions:
Productivity Index of producer | Injectivity Index of injector | ||||||
|
| ||||||
q^{\uparrow} | production rate | q^{\downarrow} | injection rate |
The PI concept also applies to aquifer expansion:
(4) | J^{\downarrow} = \frac{q^{\downarrow}}{p(t) - p_{AQ}(t)} |
where
q | volumetric water inflow rate from aquifer into hydrocarbon reservoir |
p(t) | formation pressure in hydrocarbon reservoir |
p_{AQ}(t) | formation pressure in aquifer |
See Also
Petroleum Industry / Upstream / Production / Subsurface Production / Well & Reservoir Management
Subsurface E&P Disciplines / Production Technology
[ Definition specifics on formation pressure and productivity index ] [ Sandface Productivity Index ] [ Surface Productivity Index ]