考虑储层伤害下的低速非达西斜井拟稳态产能分析

Low Speed non-Darcy Pseudo-Steady Deliverability Analysis of Deviated Wells on Considering Reservoir Damage

通过对低渗透油藏渗流特征的研究,建立了拟稳定渗流条件下,同时考虑启动压力梯度和储层伤害等因素的斜井低速非达西渗流无因次流入动态方程通式。以海拉尔盆地某低渗透油田的一口斜井为例,分析了启动压力梯度、拟表皮系数和真表皮系数等因素对斜井低速非达西渗流无因次IPR曲线的影响。结果表明,真表皮系数对IPR曲线的影响较大,在同一无因次压力下,随着真表皮系数的增大,无因次产量越低,并且无因次产量减小的幅度越来越小;拟表皮系数是由于井斜引起的,与井斜角有着密切关系,在启动压力较小时,随着井斜角的增大,拟表皮系数减小,对IPR曲线影响较小,在同一无因次压力下,无因次产量减小的幅度越来越大;只有在启动压力梯度较高时,启动压力梯度、泄油半径、平均地层压力对IPR曲线影响较大。

By study of percolation property research in low permeability reservoirs,under condition of pseudo-steady percolation,at the same time,considering the startup pressure grads and reservoir damage effects. The dimensionless general inflow performance relationship of the low speed non-Darcy deviated well has been founded. it analyzes the effects of factors such as the startup pressure grads,pseudo-skin factor and true skin factor to the dimensionless non-Darcy percolation IPR curve for a deviated well as an example in one low permeability reservoir in Hailaer basin. The result shows that true skin factor has a great effect on IPR curve,for the same dimensionless pressure,the dimensionless product is less,and the reduced product rate is more and more smaller,when the skin factor is larger; the pseudo-skin factor is caused by deviated well which has a close relationship with drift angle,a small effect on IPR curve,and the drift angle is larger while the skin factor is smaller when the startup pressure is small,for the same dimensionless pressure,the dimensionless reduced product rate more and more larger,and only when the startup pressure is higher,the startup pressure grads,drainage radius or average reservoir pressure has a great effect on IPR curve.