Discussion on several models on permeability variation in the vicinity of wellbore area

Aiming at the damage caused by fluid immersion such as drilling fluid and completion fluid, different hypothesis on the damage zones has been considered during the process of establishing geological model, and then a permeability variance diagram is qualitatively drafted. By u-sing equivalent seepage resistant method, Qiubi formula and Darcy law, the calculation method of skin factors under different models has been required.