油气二次运移过程中的运移效率探讨

依据前人物理实验结果进行的数学模拟发现,油气运移的模式决定了油气二次运移的效率.根据物理实验,油气运移模式分为活塞式、指进式和优势式3种形式.其中:活塞式的运移效率最低;指进式次之;优势式运移模式的运移效率最高.每种运移模式的运移效率特点是:活塞式运移模式的运移效率不随物理条件发生变化;指进式运移不受两相密度差和毛细管力大小的影响,并且运移路径含油饱和度值和运移的尺度有一定关系;优势运移模式的影响因素最多.在优势运移模式下,凡是对浮力和毛细管力大小有影响的物理条件都会影响其驱替效率.

Discussion on the efficiency of secondary oil-gas migration

The numerical simulations based on former physical experiments showed that the efficiency of secondary oil gas migration was controlled by oil gas migration mode. The oil gas migration mode can be divided into three types of piston mode, fingering mode and string mode. In all of the modes, the efficiency of the piston mode is the lowest, and the efficiency of the string mode is the highest. The characteristics of three migration modes are different. The oil migration efficiency of piston mode was unchanged with physical conditions. The scale of the migration space had some effects on the oil migration efficiency of the fingering mode. The efficiency of the string mode had the most complicated affecting factors. The physical conditions resulting in the change of the buoyancy force or capillary force had some affection on the oil migration efficiency of the string mode.