A Method of Calculating the Empirical Formula of Sherwood Number Between Gas and Liquid in Porous Media Using CT

Abstract

The invention relates to a method for calculating an empirical relation expression between gas-liquid Sherwood numbers inside a porous medium by applying CT. The method comprises the steps of firstly calculating the bubble volume content and a gas-liquid mass transfer Sherwood number inside the porous medium of different gas injection and liquid injection directions according to a CT image stack; calculating a liquid-phase Reynolds number according to lamellar average porosity, the bubble volume content and the liquid injection speed; classifying the acquired Sherwood numbers, the Reynolds numbers and the volume content values into different data sets according to different gas injection and liquid injection directions; dividing each data set into a plurality of different local data sets, setting a target empirical relation expression, performing local nonlinear regression analysis, and quickly searching and eliminating abnormal values which are possibly caused by the measurement process by being combined with corresponding CT images; and then performing global nonlinear regression analysis on the remaining data to acquire an empirical relation expression between gas-liquid Sherwood numbers inside the porous medium under different gravity conditions. The calculation and convergence speed of a fitting model is accelerated, a real and effective data result in the experiment process is completely covered, and the model precision is improved.

Description

technical field [0001] The invention belongs to the technical field of petroleum exploitation engineering and relates to a method for calculating the empirical formula of the Sherwood number between gas and liquid in a porous medium by using CT. Background technique [0002] For the quantitative analysis of gas-liquid mass transfer phenomena, it is very important to obtain an appropriate physical description of the relative migration between the two phases. In multiphase flow systems in many stratigraphic settings, an accurate description of phase transport requires the ability to infer the ability of a phase to migrate at interfaces between phases. Such systems are generally considered to be component multiphase flow systems. Its quantitative description needs to comprehensively consider the following points: 1. The movement of a single phase is significantly affected by the components of each phase; 2. The distribution or concentration of each phase component will affect ...

AI Technical Summary

Problems solved by technology

What is lacking at the current level of understanding includes the need for a generally accepted model of the constitutive relations for all equilibrium equations under gravity, and the typical coefficient ranges for obtaining these constitutive relations

Calculation of Reynolds number using macroscopic flow velocity or idealized model calculation will cause the data point set to deviate from the real microscopic flow situation, resulting in a reduction in the credibility of the fitting results

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