Research On Streamline Distribution And Relationship Between Streamline And Residual Oil

In order to avoid the big error caused by geological statisticaltechnique ofwell-point parameters and coarse grid approximation,a 3-D waterflooding streamlinemodel is put forward to study the residual oil saturation.At the same time, streamlinemodel also have a virtue can visual display the channel of fluid flow and coverage ofwater flood that contributes more detailed studing.To find the exact way and the shape of the fluid,this article uses many differentsimply ideal models and establishes different ideal geological models with differentwell patterns to study the distribution of streamline: establishes five-spot pattern,seven-spot pattern, nine-spot pattern, inverted five-spot pattern, inverted seven-spotpattern and inverted nine-spot patterns in homogeneous ideal models. The resultshows reservoir heterogeneity determined the display of streamline,and in a certainreservoir heterogeneity condition, distance between wells , injection rate and wellpattern also controlled the shape and way of streamline.At last,based on the current production situation of Zhao wa oilfield, simulatedthree production periods to seven layers of Zhao wa oilfield using streamline modeland numerical simulation of residual oil model.The result shows that the developmentof restraining barrier, the difference of physical property in vertical, arealheterogeneity,well patterns,the injection and the distance between wells effected thedistributione of streamline.At the same time,there are five kinds of relationshipbetween residual oil and streamline:(1)the area that streamline distributed makesresidual oil saturation low;(2) the precipitation of streamlines makes residual oillocated partly;(3) having inconsistent wells of injecting water and wells of pickingoil;(4) imperfect injection-production pattern contributes on redisual oil;(5) poorreservoir property layer makes water fluding difficult,and redisual oil saturation high.In Zhaowa oilfield,there are most intensive areas of streamline distribution is layer D1 and D2,and there is the lowest residual oil saturation sure.Layer whichlocated at the top of the stratigraphic,there are only few wells in D6 andD7,especially fewer water well,caused injected water flowed hardly and thecoverage of water flood is small.So there are high residual oil saturation in these twolayers currently,and they should be the focus of well pattern modification plan infuture.