Author(s): Peiwei Xie, Shooka Karimpour, Vincent H. Chu

Linked Author(s): Peiwei Xie

Keywords: Mountain stream, flood waves, gravel and rock mobility, shock waves, numerical simulation

Abstract: The force on gravels and rocks in mountain streams on a steep slope is studied for the role of the flood waves on the transport process. The numerical simulation using the shallow-water equations determines the height of the flood wave and the reflection of the wave by a single hemispherical rock. The goal of the simulation is to find the relevant wave parameters to replace the classical description based on Shields� critical stress for the mobility of gravels and rocks susceptible to the wave forces. The flow is constantly changing from subcritical to supercritical and back through the formation of surge waves. The flux-limiting scheme MINMOD controls the spurious oscillations across the depth and velocity discontinuity in the waves. The dimensionless parameters identified for the wave effect are the wave-force coefficient and the surge-wave Froude number. The peak values of the wave-force coefficient for the hemispherical rock are nearly constant varying from CWF ? 1. 1 to 1. 0 over a range of Froude number varying from Frs = 0. 1 to 2. 0. The critical sliding and tipping forces determine the threshold discharge for the mobility of the gravels and rocks

DOI:

Year: 2017