Mitigating Geohazards: CFD-Driven Analysis of Viscoplastic Debris Flow Impact on Resilient Oil and Gas Pipeline Design in Alpine Terrains

Debris flow is one of the catastrophic geohazard, poses significant threat to all system of infrastructure including buildings, bridges, pipelines and retaining walls. For the sustainable design of oil and gas pipeline prone to debris flow hazard, It is crucial to consider the expected debris flow impact forces to ensure the safe and effective performance of pipeline. This study numerically investigates the dynamic impact of viscous debris flow on exposed pipeline. Altair Hyperwork CFD software was utilized to perform numerical investigation in CFD environment, simulating two-phase debris flow. Hershel Bulkley rheology and Spalart-Allmaras turbulence model was adopted to simulate the complex interaction of debris flow on pipeline. The results revealed that debris flow dynamics are highly dependent on sediment composition, fine content, and flow volume. These factors significantly influence the flow behavior and its potential impact on pipeline infrastructure. Furthermore, this study highlights the critical role of impact forces due to debris flow in pipeline design to enhance the safe and longevity of pipeline system in alpine terrain. The findings underscore the need for comprehensive approach of pipeline design that integrate the advanced numerical techniques with thorough understanding of local geological conditions.