Research On The Physical Characteristics And Seepage Mechanism Of Shale Gas Reservoir

When mentioned meticulous reservoir numerical simulation, grids play animportant role in reservoir numerical simulation. The intention of this article is todiscuss the effect which is caused by the grid. The influence is discussed mainly ontwo aspects, the first is the size of the grid, the second is the shape of the grid.To the grid size, this article has proposed a method to calculate the CharacterVolume during the process of water drive at the high water cut stage. In thebackground of the core flooding, the relationship graph between production rate andtime is used and random points are added between the experiment data of controlpoints of the intercepted violent stage, and then, we use dislocation additive method toflat the violent vibration and finally make sure the vibration is not so severe that wecan regard it as a approximate smooth section, we use the size of the core to multiplynumber of times which is used in dislocation additive method. The calculated volumeis the Character Volume. Besides, the Character Volume is changing continuously, tocalculate the Character Volume under this circumstance, this article put forward amethod, this method mainly use the Stiles model and B-L equation and by anassumption that when water cut reaches up to96%, the Character Volume will change,the96%water cut is defined as the critical water cut. In each layer we calculate thetime when water cut reaches the critical value. Based on this we can figure out theCharacter Volume of the whole core.To the effect of the grid shape. Works have been done in this article mainly onhow to formulate PEBI grids, how to code with grid number and how to make anunstructure grid simulator. In order to evaluate the effect of the grid.shape, this articlemake a comparison between structure and unstructure simulator in three kinds ofmodels, the first is homogeneity model, the second is positive rhythm model, the lastis inverse rhythm model. From the comparsion, we can conclude that the shape ofequipotential lines are largely effected by the type of the grid and the difference ofshape and size between grids also effect the spread of the equiotential lines.