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许多学者从瞬态法测岩石渗透性的压差时间序列计算出渗流速度序列,发现渗流速度与压差梯度不是线性关系,认为岩石峰后存在非达西流。针对该问题,求解了瞬态法中的非稳定渗流问题解析解,发现即使在达西定律适用的情况下,瞬态法中所谓的渗流速度与压差梯度也不是线性关系。另外,利用峰后实测岩石侧向位移与渗透系数的关系、分析峰后渗流雷诺数,说明目前试验中发现的峰后高速非达西流是值得商榷的。但是随着裂隙开度的增大,水力梯度的增加,出现高速非达西流是必然的。“,”Many scholars have adopted the transient pulse method to measure rock permeability and used the time series of differential pressure to calculate seepage velocity series.They have found that the seepage velocity doesn＇t have linear relation with the differential pressure gradient,so they have thought that there exists non-Darcy flow in post-peak rock.To understand the problem,an analytic solution to the unsteady seepage problem in the transient pulse method is solved,and it is found that the seepage velocity determined by the transient pulse method is not linear with the differential pressure even if the Darcy＇s law is suitable.Moreover,by analyzing the relationship between permeability and lateral displacement of post-peak rock and by calculating some Reynolds numbers of flow in post-peak rock,it is found that the Darcy＇s law is still suitable for them.So,it needs more researches on whether there is non-Darcy flow in the researches reported by far.But,non-Darcy flow will surely occur when the hydraulic gradient and the fracture aperture are amplified.