碳酸盐岩储层参数对微观渗流的影响

The Influence of Carbonate Rocks Reservoir Parameters on Microscopic Flow

针对碳酸盐岩油藏孔隙大小的双峰分布特征,首先利用计算机模拟建立了描述不同孔隙特征的大孔隙网络模型和微孔隙网络模型,在此基础上提出一种耦合算法构建出的同时描述大孔隙和微孔隙特征的碳酸盐岩双孔隙网络模型;然后,基于侵入-逾渗理论,模拟双孔隙网络模型中油水两相流体的一次驱替和二次吸吮过程,并建立了毛细管压力和相对渗透率的求解模型;最后,通过调整双孔隙网络结构参数,模拟水湿油藏条件下碳酸盐岩储层参数对相对渗透率曲线的影响.结果表明,随着微孔隙比例因子和平均配位数的增加,油相相对渗透率曲线升高;随着双孔隙半径比的增加,油相和水相相对渗透率曲线下降,这对碳酸盐岩油藏渗流机理研究有着重要的指导意义.

Due to bimodal pore size distribution of carbonate rocks,macro pore network and micro pore network are produced to describe different pore characteristics separately,and carbonate dual pore network is constructed with the coupling of macro pore and micro pore network.Then primary drainage and secondary imbibition process are simulated based on intrusion-percolation theory during the oil-water two phase fluid flow,the capillary pressure and relative permeability model are calculated.At last,the influence of reservoir parameters on relative permeability curve is studied under water-wet conditions by adjusting the network structure parameters.Results show that oil relative permeability curve rises with the increase of micro pore density factor and average coordination number,and oil and water relative permeability curve drops with the increase of dual pore radius ratio.These phenomena are important to the study of carbonate reservoir microscopic flow mechanism.