水平井大规模压裂试井解释案例分析

Numerical Well Testing Case Analysis for Large Scale Fracture to Horizontal Well

建立油水两相渗流方程,基于PEBI网格进行数值求解,对大庆油田某多段压裂水平井的压力恢复数据进行解释与分析。研究表明,数值试井解释方法能够解释出压裂改造区域(SRV)大小、裂缝的缝长及其闭合情况。压裂设计参数下的流动很难出现第一线性流,因而当实测压力导数出现第一径向流特征时,地层裂缝可能部分闭合,这将减弱裂缝间的流动干扰,有助于形成第一径向流。相关研究对实测压力数据拟合有指导意义。

Based on PEBI grid to numerical solution to the established percolation equation of oil and water two phase,the numerical well test is applied on the interpretation of buildup pressure of multistage fractured horizontal well in Daqing oilfield.The interpretation shows that numerical well interpretation can provide the stimulated reservoir volume(SRV),fracture length and its closure.The first radial flow regime does not appear under the parameters of hydraulic fractures given by fracturing design.Therefore,if first radial flow regime appears on the curves of measured pressure derivative,some hydraulic fracture may close after a period of production,which lessens the pressure disturbance between the spaces of fracture,helps to form the first radial flow.Related research has guidance to matching of the measured pressure data.