【摘要】 用常规的压力传播的公式计算低渗透油田注水见效时间,通常与实际情况相差很大。低渗透油藏存在启动压力梯度.并且在不稳定渗流时,流体流动边界不断变化。针对低渗透油藏存在启动压力梯度的特点.以具有启动压力梯度的渗流公式为基础,利用油藏压力分布近似表达式,研究了低渗透油田不稳定渗流压力分布特征;根据物质平衡原理,求出了低渗透油田注水见效时间与注采井距的关系。低渗透油田压力传播时间与压力梯度密切相关,注水见效时间与启动压力梯度成直线关系。该方法推出的注水见效时间的公式,为油田预测注水见效时间和确定合理井距提供了一种重要的手段。更多还原

【Abstract】 The flood-response time in low-permeability reser- voirs predicted with the conventional formula of pressure transmitting coefficient deviates largely from its actual value. There exists the starting pressure gradient in low permeabili- ty reservoirs,and the flow boundary changes in the time- variant seepage.In view of the starting pressure gradient, the pressure distribution of the time-variant seepage is de- rived on the basis of the seepage flow formula with starting pressure gradient and the approximate equation of reservoir pressure.The relationship between the flood-response time and the well spacing is established in line with the principle of material balance.The pressure travel rime is closely corre- lated with the pressure gradient in low permeability reser- voirs,and there exists a positive correlation between the flood-response time and the starting pressure gradient.The formula of flood-response time presented in this paper pro- vides a significant method to predict the flood-response time and to arrange the well spacing.更多还原