Calculation method for imbibition effect wetting-phase relative permeability under mixed boundary conditions

The invention relates to the technical field of oil development and specifically discloses a calculation method for imbibition effect wetting-phase relative permeability under a mixed boundary condition. The method mainly comprises the following steps : S1, determining a function relation between a one-dimensional mixed boundary imbibition time and an imbibition mining degree, S2, obtaining a function relation between the differential of the imbibition time to the imbibition mining degree and the imbibition mining degree; S3, obtaining the slope and intercept of a linear segment of the function relation between the differential of the imbibition time to the imbibition mining degree and imbibition extraction degree; S4, obtaining an expression of E and D; S5, obtaining an expression of theimbibition effect wetting-phase relative permeability under the mixed boundary condition; and S6, calculating a wetting-phase relative permeability value of the imbibition effect under the mixed boundary condition. According