Numerical Study of Coal-Air Mixture Erosion with Vane Addition in Elbow Coal Pipe

Abstract

Background: Erosion in elbow coal pipes is a recurring problem in coal-fired power plants because the interaction between coal particles and airflow can cause localized wall thinning, leakage, and reduced reliability of the coal transport system. Objective: This study evaluates the effects of vane position and radius on coal-air flow characteristics, erosion distribution and rate, and estimated pipe remaining life, validates the CFD model against field thickness measurements, and identifies the most suitable vane configuration among six alternatives. Methods: A comparative numerical study was conducted using Computational Fluid Dynamics (CFD) in ANSYS Fluent 2024 R2. The simulation employed the realizable k-ε turbulence model, Discrete Phase Model (DPM), DNV erosion model, and one-way coupling under steady-state conditions. Six vane configurations were evaluated using positions of 0.5D and 0.75D and radii of R1100, R1250, and R1400. Results: Validation at Patch A produced a relative error of 4.53%. The six configurations produced different erosion and remaining-life characteristics due to changes in flow distribution and particle impact. The 0.75D-R1250 configuration produced an erosion rate of 0.07 kg/m²s at Patch A and an estimated remaining life of 71.12 years, while its vane erosion rate was 9.67 kg/m²s. Conclusion: The results demonstrate that vane position and radius influence erosion mitigation and flow behavior in elbow coal pipes. The findings provide a numerical basis for selecting vane configurations and prioritizing inspection and maintenance of erosion-prone coal pipe sections at PLTU Banten 3 Lontar.