| The commonly used commercial numerical simulation software is based on the multi continuum model, and it adapts to the normal oil zone. But such software can't satisfy the development of reservoirs with Macro fracture. The condensate gas reservoirs of Qianmiqiao and Su 1 are mainly droved by gas, but since there are affected by the steep big fracture, the bottom water rises fast and water production rate is high. The predicted water rate tends lower through simulating by using numerical simulation software, such as CMG and ECLIPSE.Some researchers analyzed the shortcomings of the multi continuum models and presented some new percolation models. Some of them supposed that permeability principal axis of macro fracture in the, multi-continuum were consistent with reservoir coordinates direction and this assumption made it impossible to predict the bottom water coning. Others thought that that multi-continuum models could not be used to predict bottom water coning was resulted from the applying Darcy flowing in all the medium percolation equations. In this paper, the characteristics of oozing and reserving such as high permeability and limited storage volume of macro fracture are considered as the main cause that makes the bottom water flow into the well and water cut increase rapidly. Only if the established percolation mathematical models reflect the oozing and reserving characteristics, numerical simulation will be able to solve the coning problem of bottom water in the reservoir with big fracture.This paper also studied solution hole, another medium in the carbonate. The study on percolation regularity of oil zone in the carbonate can't avoid the investigation on solution hole and macro-fracture. While dealing with fractures in carbonate, this paper divided them into macro-fractures and micro-fractures. In the simulation models, the micro-fractures were treated as continuums and macro-fractures as discrete fracture mediums. This method integrated the advantages of continuum model and discrete fracture model. While dealing with solution cavity, this paper regards that the relationship between solution cavityand fracture is the same as pore and pore throat and suggests that solution cavity and fracture constitute a medium. Solution cavity mediums were divided into four types and three of them were disposed in this paper. The first kind of solution cavity is treated with dual continuum model; the second kind was dealt with big fracture multi-medium model, and this model can be used to manage the reservoir with class I and class II solution cavity; for the third class solution cavity medium, "Class III Solution Cavity" multi-medium component model is presented in this paper. The different equations can be chosen to meet the practical needs according to whether there is big fractures and solution cavities in the grid block or not. The combination of big fracture numerical simulation model and solution cavity medium model forms a new multi-medium percolation model including macro-fracture, solution cavity, micro-fracture and matrix which can be used more widely. This model is also called micro-fracture-solution cavity and multi-medium component model for short, and its main characteristics are as follows:In this paper, the macro-fractures are idealized as a series of slabs, and the maximum permeability principal axis is placed on its tangent plane. Two series of coordinates were introduced into the mathematical model of big fracture multi-medium component model: reservoir coordinates and big fracture variable coordinates. At the same time, two series of grid system, reservoir grid system and macro-fracture grid system, were also introduced in the mathematical model.The class III solution cavity medium is regarded as the rectangular part that is enclosed by the dual medium constituted by matrix and micro fracture. The conglomeration matrix with solution cavity appears as correspondingly independent non-continuum.At last, a numerical simulator was made by using Matlab and its proof-test was done. This...
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