The invention discloses a method for simulating water
injection well water pressure drive fracture extension dynamic. The method comprises the following steps that an oil reservoir geological characteristic parameter of a target water
injection well with fractures is obtained according to the oil reservoir geological study; a water
injection well water pressure drive hydraulic fracture
extended model is established with the integration of a
Darcy leak-off model, a
continuity equation, a matter
balance equation and an initial condition;
fluid volume filtered into a stratum is used as a source item based on an oil-water two-
phrase seepage model of a seepage
mechanics theory, the boundary condition is established by combining the
fluid pressure in the fracture, a hole elastic deformation relationship between a fluid body and a rock is established by being combined with a boundary condition established by the
fluid pressure in the fracture, that is, a fluid-
solid coupling model is established, and the formation pore pressure is calculated and strain and a pore penetration change which are caused by a change in the
fluid pressure are obtained; and then the fracture extension dynamic after the action of the fluid-
solid coupling is obtained, then the obtained new parameter is used as an initial condition to be repeated, and finally the fracture extension dynamic is obtained. Accordingto the method for simulating the water injection well
water pressure drive fracture extension dynamic, the
dynamic extension condition of the fracture in a water injection well and the dynamic changecondition of the parameter in a reservoir can be forecasted according to the construction and geological parameters.