Numerical simulation method capable of taking nonlinear percolation feature of tight sandstone reservoir into consideration

Abstract

The invention relates to a numerical simulation method capable of taking the nonlinear percolation feature of a tight sandstone reservoir into consideration, which includes the following steps: a micro-tube experiment is carried out on a target tight sandstone reservoir, and the boundary layer thickness of the target tight sandstone reservoir is calculated; a relation between the boundary layer thickness of the target tight sandstone reservoir and pressure gradient, throat radius and fluid viscosity is fitted; a mercury injection experiment is carried out on the target tight sandstone reservoir, and an experimental result is fitted, so that a relation between the capillary force of the target tight sandstone reservoir and mercury saturation is obtained; the relation between the boundary layer thickness of the target tight sandstone reservoir and pressure gradient, throat radius and fluid viscosity and the relation between the capillary force and mercury saturation are substituted into a Poiseuille equation and integration is carried out, so that a nonlinear motion equation is obtained; according to the nonlinear motion equation, a nonlinear mathematical model for the target tight sandstone reservoir is established; the nonlinear mathematical model for the target tight sandstone reservoir is solved, and thereby the productivity of the target tight sandstone reservoir taking nonlinear curved sections into consideration is obtained.

Description

technical field [0001] The invention belongs to the field of numerical simulation research of tight sandstone reservoirs, and in particular relates to a numerical simulation method considering nonlinear seepage characteristics of tight sandstone reservoirs. Background technique [0002] Tight sandstone reservoirs have low permeability and significant nonlinear seepage characteristics, which have a great impact on oilfield productivity and seriously affect the prediction accuracy of oilfield productivity. However, if figure 1 As shown, the current numerical simulation method usually simplifies the curved section in the nonlinear seepage characteristics to a straight line that does not pass the origin, as shown by the dotted line in the figure, resulting in low prediction accuracy. There are no relevant reports on numerical simulation methods considering the characteristics of nonlinear curved sections of tight sandstone reservoirs. Contents of the invention [0003] In vi...

AI Technical Summary

Problems solved by technology

[0002] Tight sandstone reservoirs have low permeability and significant nonlinear seepage characteristics, which have a great impact on oilfield productivity and seriously affect the prediction accuracy of oilfield productivity

However, if figure 1 As shown, the current numerical simulation method usually simplifies the curved section in the nonlinear seepage characteristics to a straight line that does not pass the origin, as shown by the dotted line in the figure, resulting in low prediction accuracy

No relevant reports have been found on the study of numerical simulation methods considering the characteristics of nonlinear curved sections of tight sandstone reservoirs

Images