Stanford Geothermal WorkshopFebruary 9-11, 2026

Lost circulation remains one of the most critical challenges in geothermal drilling, threatening wellbore integrity and causing significant non-productive time. Fiber-based lost circulation materials (LCMs), valued for their flexibility and cross-scale bridging capability, are widely applied for fracture sealing. However, their transport, deformation, and entanglement mechanisms under high-temperature conditions remain insufficiently quantified. Temperature variations not only alter fluid density, viscosity, and heat capacity but also affect the Young’s modulus and durability of fibers, making the sealing mechanisms more complex than in conventional oil and gas drilling. In this study, a three-dimensional coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) framework is established, incorporating dynamic material and fluid parameters to capture the real-time influence of temperature on sealing processes. Comparative simulations under varying temperature conditions reveal three key findings: (1) elevated temperatures significantly prolong the time needed to seal the fracture; (2) the critical fiber length threshold of successfully sealing the fracture shifts upward 20% under high-temperature conditions; and (3) maximum sealing pressure capacity decreases 15% with increasing temperature. A temperature-sensitive performance index is further introduced to quantitatively link micro-structural evolution with macroscopic sealing efficiency. This work extends the quantitative analysis of lost circulation mechanisms to high-temperature and supercritical geothermal drilling environments, offering theoretical guidance for the design and optimization of fiber-based LCMs. The results provide new insights for improving wellbore integrity and ensuring sustainable development of high-enthalpy geothermal reservoirs, while demonstrating the potential of CFD-DEM as a mechanism-driven design tool.

Topic: Modeling