Erosion mechanisms of packer center tubes under high-temperature liquid–solid flow: experimental investigation and CFD–DPM simulation

Erosion induced by high-velocity sand-laden flow poses a major threat to the integrity and service life of downhole packers in high-temperature and high-production wells. To clarify the coupled thermo–hydrodynamic–mechanical mechanisms governing this degradation, this study develops a coupled computational fluid dynamics–discrete phase model (CFD–DPM) capable of resolving particle–wall interactions, fluid–solid coupling, and turbulence-driven energy dissipation. Controlled erosion experiments were conducted to benchmark the numerical predictions, ensuring reliable representation of erosion behavior under liquid–solid two-phase flow. A comprehensive systematic parametric analysis was performed to quantify the effects of fluid velocity (5–35 m/s), temperature (160–220°C), particle size (1–4 mm), solids loading (0.5–5.0 kg/s), and diameter ratio (0.35–0.80) on erosion severity in packer center tubes. The results show that the maximum erosion rate increases by up to 25.5 times with fluid velocity and by 8.3 times with higher solids loading, whereas larger particles and greater diameter ratios reduce erosion by 83% and nearly three orders of magnitude, respectively. Temperature contributes less than 2% to erosion magnitude but modifies morphology by altering viscosity and turbulent structures. Flow-field diagnostics further reveal that vortex enhancement and particle-impact clustering near contraction zones dominate localized severe wear. By integrating experimentally benchmarked modeling with multi-parameter mechanistic analysis, this study provides quantitative insight into erosion evolution in packer components and offers practical guidance for structural optimization and service-life extension in high-temperature well operations.