摘要
火山岩气藏发育多尺度孔、洞、缝介质,压裂水平井投产具有多重介质接力排供气与非线性渗流的特征。引入新的拟压力函数,以等值渗流阻力法及叠加原理为基础,综合考虑气体滑脱效应、启动压力梯度、应力敏感效应及裂缝内紊流效应,构建了火山岩气藏水平井压裂多条横向裂缝相互干扰的产能预测新方法。结果表明:在气井生产过程中,近井筒附近,裂缝内需考虑紊流效应影响,启动压力梯度对气井产能影响最大,其次是应力敏感效应与紊流效应,滑脱效应影响最小;随着水平井段长度减小,裂缝条数增加,裂缝间干扰越严重,水平井段长度与裂缝条数存在一最佳匹配关系;随着裂缝半长增加,气井产量增大;裂缝导流能力变化对气井产量影响最明显,导流能力越大,气井累计产量越高,裂缝导流能力增加到一定程度时,气井产量随着导流能力增加幅度减小。
With multi-scale pores and cracks,fractured horizontal well in volcanic gas reservoirs demonstrates the features of relay gas production among multiple media and complex nonlinear flow.Based on the equivalent flowing resistance method and superposition principle,a new productivity forecasting method for fractured horizontal well with multi transverse fractures considering interference in volcanic gas reservoirs is established on a new pseudo-pressure function,with the consideration of comprehensive effect of gas slippage effect,starting pressure gradient,stress sensitivity effect and turbulence effect in fractures.The simulation results show that during the production process of fractured open-hole horizontal well,the turbulence effect in fractures around the well hole needs consideration,and the starting pressure gradient has the most remarkable impact on gas well productivity,followed by pressure-sensitive effect and turbulence effect,and the slippage effect has the smallest influence.The longer the length of horizontal well and the more the number of fractures,the stronger the interference of multi fractures on gas production.There is an optimum relationship of the length of horizontal well and the number of fractures.Gas well production increases as the fracture half-length and fracture conductivity capacity increase.The most obvious influencing factor of gas well production is fracture conductivity capacity.
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2014年第11期1868-1874,共7页
Natural Gas Geoscience
基金
国家高技术研究发展计划("863"计划)"致密砂岩油气藏数值模拟技术与软件"(编号:2013AA064902)
中国石油勘探开发研究院院级项目(编号:2012Y-043
2012Y-042)联合资助
关键词
火山岩气藏
压裂水平井
启动压力梯度
应力敏感
紊流效应
裂缝干扰
Volcanic gas reservoir
Fractured horizontal well
Starting pressure gradient
Stress sensitivity
Turbulence effect
Multi fractures interference
