Study On Mathematical Representation And Flow Law Of Foam Formation

China's demand for petroleum energy is increasing,and the difficulty of petroleum exploration is increasing.Foam flooding technology is a kind of three-stage oil recovery technology with dual action mechanism of profile control and oil displacement.However,the seepage mechanism of foam flooding system in porous media is very complex,and the mathematical characterization of seepage mechanism is more difficult than other flooding systems.It is of great significance to study the seepage characteristics and mathematical characterization of foam flooding.Based on the analysis of the existing bubble generation rate model and the bubble rate model established on the basis of the advantages and disadvantages and applicable scope of the new foam generation rate model and the bubble rate model,through the definition of chemical reaction rate with hypothesis testing method to determine the reaction series of bubble formation rate,and through the inverse calculation of dimensional analysis and model of surfactant concentration decline curve and measured curve contrast verify the accuracy of the model.Experimental study on the different pore structure and characteristics of bubbles generated under the conditions of different concentration of foaming agent,the results show that the greater the coordination number of foam porous media,the more concentrated the bubble size distribution,the bigger the peak value.On the contrary,the lower the coordination number of porous media,the more dispersed the size of the generated foam,the greater the mean value.The higher the concentration of foaming agent,the smaller the size of the foam particles,the more even the foam.With the same concentration of foaming agent,the longer the migration distance of foam is,the larger the size of foam particles is,and the uniformity of foam size decreases.Foam particle size will change continuously during foam flooding,and there is an optimal matching relationship between foam particle size and pore throat of porous media.Experimental study on the bubble and the matching of porous media's influence on the effect of foam flooding,the results show that foam flooding in the process of the system and porous media will happen "second match" phenomenon,this phenomenon using foam flooding enhance oil recovery,and through the experimental data and theoretical analysis demonstrates the phenomenon of "secondary matching degree of contribution to the foam flooding recovery efficiency is about 1.7%.