Producing degree and law of matrix in dualporosity reservoir

Key words:  dualporosity reservoir  matrix contribution rate  influencing factors  size index  water injection rate

Abstract:

The matrix producing mechanism, degree and influencing factors in dualporosity reservoir were studied by numerical simulation method. Since the software of ECLIPSE can not calculate the matrix production, a new method for calculating the matrix cumulative oil production using saturation change was proposed. The concept of matrix contribution rate was introduced to research the matrix producing degree. The effect of size index, matrix permeability, fracture permeability, water injection rate on the matrix contribution rate of water flooding was analyzed. The results show that the degree of fracture development is the main factor affecting the matrix producing degree. The more the fracture developed in the reservoir, the more obvious the effect of imbibitions oildrain in matrix and the higher the matrix contribution rate is. The higher matrix permeability, the higher matrix contribution rate is. Fracture permeability has relative small effect on the matrix contribution rate. The lower water injection rate, the better matrix imbibitions oildrain effect is.