Modeling method of water lock effect damage to oil and gas reservoirs, 4d quantitative and intelligent diagnosis method and system of temporal and spatial evolution of damage degree

Abstract

The invention relates to the technical field of oilfield exploration, and discloses a modeling method for water lock effect damage to a reservoir, a method for determining the damage degree of the reservoir, and a system thereof. The modeling method includes: determining the Darcy superficial velocity of the fluid in the reservoir within the preset area of ​​the well to be diagnosed; establishing the Darcy superficial velocity of the fluid and the diffusion coefficient of the water molecules in the fluid The water phase motion equation of the reservoir; the distribution equation of the permeability of the reservoir is established according to the pore size distribution characteristics of the pores of the reservoir and the preset permeability model of the reservoir; and according to the permeability The distribution equation of the rate and the motion equation of the water phase are used to determine the temporal and spatial evolution simulation equation of the reservoir damaged by the water lock effect. The invention can quantitatively simulate the four-dimensional space-time evolution process of reservoir damage characteristics caused by the water lock effect, so as to carry out quantitative prediction of reservoir damage and space-time deduction of damage laws for wells without reservoir damage.

Description

technical field [0001] The invention relates to the technical field of oilfield exploration, in particular to a modeling method and system for water lock effect damage to reservoirs and a method and system for determining the degree of reservoir damage. Background technique [0002] In each period of oilfield exploration and development, due to the influence of various internal and external factors, the original physical, chemical, thermodynamic and hydrodynamic equilibrium state of the reservoir will change, which inevitably causes the reservoir near the wellbore wall and even far from the wellbore wall. The internal permeability of the reservoir is reduced, the fluid flow is blocked, the reservoir is damaged and the production of the oil well is reduced, and even the reservoir is "shot". The causes of reservoir damage are various and complex, especially during the production process, the reservoir rock storage and seepage space, surface wettability, hydrodynamic field, tem...

AI Technical Summary

Problems solved by technology

The core flow test method is to understand the degree of damage through the change of permeability before and after core displacement. Although it is more suitable for studying single-factor reservoir damage, it is difficult to reflect the law of reservoir damage on a large scale

In addition, due to the ideal conditions of the indoor core experiment, the cores used for evaluation are all original state cores, and the dynamic changes of reservoir properties cannot be considered, so the experimental results are quite different from the real damage of the downhole reservoir.

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