确定注蒸汽开发稠油油藏原油采收率的三参数注采特征曲线法

三参数注采特征曲线能够很好地揭示累积注汽量与累积产油量之间的半对数线性关系，可以用于注蒸汽开发稠油油藏原油采收率的计算。针对三参数注采特征曲线不能采用常规的最小二乘法确定模型参数的问题，提出了求解模型参数的两种简单方法，即线性回归法和等步长法。线性回归法仅适用于汽油比有规律增大的油藏，而等步长法与汽油比无关，适用范围较线性回归法要广。通过实例验证表明，用三参数法计算稠油油藏原油采收率是适用、有效的

Determination of oil recovery through typical 3 parameters injection production curves

Typical 3 parameters injection production curve can reflect the semi log linear relationship of accumulated steam injection and accumulated oil production, so it can be used for the calculation of recovery factor of heavy oil reservoir developed by steam injection. Since conventional least square method cannot be used for the determination of the model parameters from 3 parameters of injection production curves, two simple methods were proposed to find the solutions of model parameters. While linear regression can only be used for oil reservoirs where steam oil ratio increases regularly, iso step length method, which has nothing to do with steam oil ratio, is suitable for a wider range than linear regression method. Examples indicate that it is fit and effective to calculate recovery factor of viscous oil reservoir through 3 parameters injection production curve.