Martin Kern

Practical application of granular mechanics in avalanche research.

Abstract: For most practical applications, snow avalanches are treated within the framework of continuum mechanics. However, the inverse grading of snow particles in the deposits of snow avalanches indicates that aspects of granular mechanics play a role in the dynamics of flowing avalanches. The avalanche airbag which helps to prevent people to be buried by flowing avalanches makes use of the inverse grading effect in granular flows.
We use a simple numerical model of granular flow of different sized particles to reproduce the observed inverse segregational behaviour. Evidence is presented that the time dynamics of the vertical displacement of individual particles has Markovian properties. The deterministic part of the vertical segregation process can be expressed in the simple formal shape of an ODE.