Experimental And Predictive Study Of The Law Of The Oil Relative Permeability Under Three-Phase Flow Conditions

When studying a production from an oil reservoir, there are many situations where the flow of all three phase-oil, gas and water must be considered. The water drive, steam drive, underground combustion, solution gas drive and gas cap drive often involve simultaneous flow of all three phase. Application of enhanced oil recovery techniques that utilize injection of gas or light hydrocarbon are frequently accompanied with three-phase flow. To understand the fluid movement, estimates of three-phase relative permeabilities are needed. While the measurement of three-phase relative permeability poses a particular challenge. In addition to the measurement of saturations, pressure drops, and fluxes in three flowing phases, there are an infinite number of different involves the variation of two independent saturations. Thus, most of the reservoir engineering calculations for processes involving three-phase flow are based on predictive models that attempt to estimate the three-phase relative permeability from more easily obtained two-phase oil-water, oil-gas and water-gas relative permeability measurements. This paper determines two-phase and three-phase relative permeabilities of different permeabilities and wettabilities by using water-wet cores and oil-wet cores in order to make more studies in the flowing law of oil and gas reservoirs. First of all, we study the flowing law of two-phase gas-water, oil-water and gas-oil in different factors. The experiment results indicate that wettability is strongly impact on the flowing law and permeability is a little impact on the flowing law. Secondly, we study the three-phase oil relative permeability in different wettabilities. The experiment results indicate that oil relative permeability of water-wet cores and oil-wet cores are dependent on saturation of all phase. The oil isoperms of water-wet cores are concave toward the oil apex. The oil isoperms of oil-wet cores are convex toward the oil apex. Finally, several different prediction models are selected for evaluation. It is found that the accuracy of three-phase oil relative permeability models is strongly influenced by the wettability of the medium being considered. No single three-phase model is capable satisfactorily matching the experiment datas. Some models are fit to water-wet medium and others are fit to oil-wet medium.