Numerical simulation method and device for micro-nano pore bubble point pressure in ultra-low permeability oil and gas reservoirs

Abstract

The present invention provides a method and device for numerically simulating micro-nano pore bubble point pressure in ultra-low permeability oil and gas reservoirs, wherein the method includes: determining the equilibrium coefficient; determining the liquid phase compression factor according to the equilibrium coefficient, capillary pressure and surface tension, and According to the equilibrium coefficient, determine and normalize the gas phase mole fraction; according to the gas phase mole fraction, capillary pressure and surface tension, determine the gas phase compressibility factor, fugacity coefficient and fugacity; according to the liquid phase compressibility factor, fugacity Fugacity coefficient and fugacity, as well as gas phase compression factor, fugacity coefficient and fugacity, determine the ratio of liquid phase and gas phase fugacity; according to the ratio, judge the balance of gas phase and liquid phase fugacity, if it is unbalanced, correct the balance coefficient and Corresponding to the bubble point pressure, until the fugacity of the gas and liquid phases equilibrates. The above-mentioned technical scheme improves the numerical simulation accuracy of nano-pore multi-component fluid bubble point pressure in ultra-low permeability oil and gas reservoirs, thereby improving the accuracy of production prediction of ultra-low permeability oil and gas reservoirs.

Description

Technical field [0001] The present invention relates to the numerical simulation technique of dense sandstone oil hood, and in particular, to a micronine-pore bubble point pressure numerical simulation method and apparatus for ultra-low osmotic oil gas storage. Background technique [0002] At present, the amount of ultra-low osmotic oil reservoir resources is increasing in the amount of low penetration remaining available resources. Ultra-low osmotic oils have micro-nano-scale pores, which are complex, and the permeability is extremely low, and the oil and gas PVT phase changes are different from conventional oil gas, and therefore, the use of conventional multi-component simulation schemes often result in yield prediction results Different from the actual difference. Inventive content [0003] The embodiment of the present invention provides an ultra-low osmotic oil gas-hiding microbioprotic bubble point pressure numerical simulation method for improving the numerical simulati...

AI Technical Summary

Problems solved by technology

Ultra-low permeability oil and gas reservoirs have micro-nano scale pore throats, complex structures, and extremely low permeability. The PVT phase change of oil and gas in them is different from conventional oil and gas reservoirs. Therefore, the production prediction results obtained by conventional multi-component simulation schemes are often Big difference from the actual

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