考虑基岩向井筒供气的气藏压裂水平井产能预测模型

基于等效井径模型,综合考虑各裂缝不同参数、裂缝变质量入流和井筒变质量流动等因素的影响,建立并求解了基岩和压裂缝同时向井筒供气的井筒与气藏耦合的压裂水平井产能预测模型.研究分析了压裂水平井产能敏感因素.结果表明:压裂水平井的产能随裂缝条数、裂缝半长、裂缝间距的增加而增加;为获得较高的产能,压裂时应尽可能保持裂缝与井筒垂直;压裂缝条数一定时,裂缝越长、间距越大,压裂缝产能贡献越大,而裂缝越短、间距越小时,基岩向井筒供气的贡献越大,压裂缝贡献相对较小.研究成果为气藏压裂水平井设计提供了科学依据.

Productivity Prediction Model for Fractured Horizontal Wells Considering the Gas Rate of Matrix Flowing Into Wellbore

In this paper,we established and solved the coupling model of gas reservoir percolation,fracture percolation and wellbore percolation for fractured horizontal wells basis on the equivalent wellbore.In this model,the parameters and variable mass flow of fracture and variable mass flow of wellbore are considered.The sensitive factor on productivity is studied.The results show that the productivity increase as the fractures number,space,halflength and conductivity increase.In order to get the higher production,the fracture should be perpendicular to wellbore.The bigger the fracture length and space,the bigger the fracture productivity contribution is.Conversely,the bigger the matrix productivity contribution is.The study results is significant in the design of fractured horizontal wells on gas reservoir.