Rheological Modeling and Flow Dynamics for the Bhotekoshi River Corridor
DOI:
https://doi.org/10.64862/Keywords:
Hydrodynamic modeling, Voellmy-salm model, Ice-rock avalanche, Gorge fluctuations, Infrastructure vulnerabilityAbstract
This study investigates the flow dynamics, flow velocity attenuation, impact pressures, and wave height evolution of the catastrophic rock-ice avalanche and subsequent debris flood cascade originating from Langtang Lirung on August 26, 2026. Utilizing the Rapid Mass Movement Simulation (RAMMS) framework governed by Voellmy-Salm rheology, we numerically track the 198 km hazard corridor incorporating localized gorge geometry, channel bends, and secondary constriction points between 20 and 30 km. The simulation reveals severe hydrodynamic oscillations reaching peak velocities of 42.0 m/s and impact pressures exceeding 3,175kPa in confined reaches showed vulnerable infrastructures and settlements.
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