煤层气非对称垂直裂缝井产能研究

摘要

Focused on asymmetry vertical fracture well in coalbed methane reservoirs,we have applied to the law of conservation of mass with steady percolation.We think the conformal transformation theory could be used in drawing deliverability predicting model of asymmetry vertical fracture well.Then,an influence of various factors on deliverability was analyzed in field experience.Results indicate that,in same flowing bottom hole pressure,fracture asymmetry ratio influences gas well deliverability is slight.With high fracture conductivity,the influence degree of fracture asymmetry ratio and fracture length on gas deliverability differs slightly.With small fracture conductivity,the influence degree of fracture asymmetry ratio and fracture length on gas deliverability differs significantly.The smaller the fracture asymmetry ratio is,the greater the fracture length is,and the more remarkable the gas well deliverability will be.%针对煤层气压裂后产生的非对称垂直裂缝井,利用保角变换,基于质量守恒定律和稳定渗流理论,建立了非对称垂直裂缝井产能预测的模型,同时使用实例分析了各种因素对产能造成影响.结果表明:井底流压相同时,裂缝非对称率对气井产能影响较小;裂缝导流能力较大时,裂缝非对称率及裂缝长度对气井产能影响程度的差异性较小;当裂缝导流能力较小,裂缝非对称率及裂缝长度对气井产能影响程度差异较大;当裂缝非对称率越小,裂缝越长,对气井产能影响越大.