井壁稳定多场耦合分析研究进展

井壁稳定问题是石油钻井过程中十分重要的问题，而地层流体、钻井液性能、温度等因素对井壁稳定有重要影响。通过对目前国内外井壁失稳分析的研究现状进行总结，将钻井过程中井壁失稳的影响因素分为岩石结构场、应力场、渗流场、温度场和化学场等5类作用场，分析了这5类作用场的具体内容及产生原因，由此对井壁失稳多场耦合的作用场影响和发展现状进行了较为系统的分析。在进行井壁失稳多场耦合分析时，应力场和岩石结构场是研究的基础，在总结国内外井壁失稳研究方法的基础上，对岩石结构类型和岩石变形机制进行了分类；以岩石结构场和应力场为基础，结合其他3种作用场的影响，着重分析了包括三场、四场和五场耦合在内的井壁稳定多场耦合研究发展现状；对于四场和五场耦合分析而言，孔隙介质热弹性理论和孔隙介质化学热弹性理论应用较为广泛。最后结合不同作用场的特点和现代钻井工艺的发展方向展望了其发展趋势。

A Review on Wellbore Stability with Multi-Field Coupling Analysis

Wellbore stability is greatly affected by various factors, such as the formation fluid, and the properties and temperature of the drilling fluid, and is critical to petroleum drilling. By summarizing the actuality of wellbore instability analytical studies both locally and globally, the influencing factors of wellbore instability during drilling were divided into five fields:rock structure, stress, seepage, temperature, and chemical. Their detailed contents and causes were analyzed, based on which the impact of multi-coupling on wellbore instability was systematically analyzed. The stress and rock structure fields were the basis for the research on multi-coupling analysis of wellbore instability. The rock structure types and rock deformation mechanism were classified by summarizing the research methods of wellbore instability both locally and globally. The three-field, fourfield, and five-field coupling wellbore stability studies was based on the rock structure and stress fields combined with three other fields; pore medium-thermoelastic theory and pore medium-chemical-thermoelastic theory have been widely used in fourfield and five-field coupling analysis. To conclude, the development tendency of multi-coupling analysis was explored with the features of different fields and the development of drilling technology considered.