Research progress on fluid structure interaction simulation of artificial lift systems in deep and ultra-deep wells

In deep and ultra-deep wells, conditions such as pressure, temperature, and wellbore intervals exhibit significant variations. Fluid flow and tubing string vibration behaviors are highly complex, and the associated fluid-structure interaction (FSI) issues are characterized by strong multi-physics field interactions, prominent nonlinearity, and large scale spans. As a core technology for revealing the interaction mechanisms between fluid flow and tubing string structures, FSI simulation provides critical technical support for performance optimization, pump setting design, and fault diagnosis and prediction of artificial lift systems under complex operating conditions. This paper comprehensively reviews the research status of FSI simulation for artificial lift systems in deep and ultra-deep wells, focusing on analyzing the FSI mechanisms, numerical simulation methods, multi-field coupling technologies, and engineering application cases of mainstream lift methods including rod pumps, rodless pumps, and gas lift. Additionally, the technical challenges and future development trends in this field are discussed. The study indicates that FSI simulation technology for deep and ultra-deep well artificial lift systems is evolving from single-physics field analysis towards multi-scale, interdisciplinary integration, and intelligence. Technological breakthroughs in this domain will significantly enhance the performance, stability, and service life of artificial lift systems in deep and ultra-deep wells.