<< Click to Display Table of Contents >> Navigation:  Input Panels > IPR Types > Gas Injector IPR Options: > BackPressure II

Back Pressure II

 

 

 

The following items may be edited on the Fractured Reservoir Data Panel:

 

RESERVOIR PRESSURE (psia):  The average reservoir pressure in the well's drainage area and can be obtained from pressure buildup analysis.

 

FRACTURE PRESSURE (psia):  The pressure at which the slope of the injectivity index changes as the reservoir begins to break-down  Typical frac gradients run from 0.7 to 1.2 psi/ft.

 

MATRIX II (mscfpd/M(p)):  The injectivity index of the formation prior to fracturing.  The units are in mscfpd per change in real gas pseudo pressure.  Although this is the most rigorous set of units, they will also be the most unfamiliar to most engineers.

 

ABOVE FRAC II (mscfpd/M(p)):  The injectivity index of the formation after fracturing.  This value should be greater than the below frac II.  The units are in mscfpd per change in real gas pseudopressure.  Although this is the most rigorous set of units, they will also be the most unfamiliar to most engineers.

 

HIGHEST EXPECTED INJECTION RATE (mscfpd):  Unlike an IPR curve, the Injectivity performance of the reservoir is bounded only by the ability to pump more fluids into the formation.  To set a reasonable bound on the Injectivity, enter the highest anticipated injection rate here and the IPR calculations will build a suite of points to cover rates from 0 to the value you entered.  Entering a very large number will ensure a valid intersection is reached, but may reduce the resolution of the ipr curve.