A new inflow performance equation for the IPR curves with maximum flow rate and its application

The performance data from more waterflooding oilfields exhibit a new IPR curve concaving to the pressure axial and showing a maximum flow rate point. Combining pseudo-stable flow equation with relative flow behavior equation of oil and liquid phases leads to the establishment of a new inflow performance equation that can describe the IPR curve with maximum flow rate point. The equation can be used effectively to analyze and predict production behavior of some water-flooding oilfields and to derive an equation to determine the flowing pressure limit for stabilizing oil recovery rate with increasing liquid recovery rate. The comparison of the calculations with the field measurements verifies that the equation can meet the accuracy requirements in the context of reservoir engineering and can determine the allowable minimum flowing pressure of production well.