Study On The Rule Of Vertical Flow And Its Influence On Development In Sandstone Reservoir

When reservoirs enter the ultra-high water cut stage,the yield production sharply declines and the water cut is quickening up.Water flushing zone thickness is relatively thin especially for severe heterogeneity positive rhythm layers,leading to completely water flooding in bottom reservoir and a large amount of remaining oil left in high position.Based on the situation above,the difficulty of tapping the potential of the remaining oil and maintaining stable production is increasing and the contradiction between layers highlights.It is necessary to figure out the flowing characteristics and mechanisms of oil and water phases in reservoir vertical direction.The movement of oil and water is complex and variable and its flow rules is influenced by lots of forces.This article elaborates the features of the forces which have effect on oil and water flowing law in reservoir vertical direction and puts forward clearly the occurrence of the conditions by analyzing vertical flow influencing factors from reservoir properties,fluid properties and development conditions.By means of establishing typical models controlled by single force and a variety of forces,we can conclude its corresponding vertical seepage characteristics.On this basis,we protract vertical flow rules plate and put forward comprehensive index which can evaluate the effect of development.Finally,we come up with targeted simulation treatments for different kinds of reservoir and production conditions,offering theoretical guidance on tapping remaining oil for reservoirs at ultra-high water cut stage.