Establishment and Application of a Water-drive Curve Based on Relative Permeability Following Power Function

Abstract

Based on Buckley-Leverett theory of water flooding in non-piston way, fractional flow equation, Welge average water saturation equation and the relative permeability curve, a new relationship between water cut and recovery efficiency and the corresponding water drive characteristic curve are derived making use of the general solution of ordinary differential equation formula with the initial condition. The ratio of oil-water relative permeability follows the power function in the process of derivation. It is different from the previous derived methods of water displacing curves to consider the effect of water-free oil production period on water drive type curve in this paper. The practical application in K oilfield indicates that the method is rational and effective.