Application of Numerical Transient Fluid Dynamics to Snow Avalanche Flow. Part II. Avalanche Modeling and Parameter Error Evaluation

Abstract

AbstractUnder evaluation is the range of the parameters of internal viscosity and surface friction of flowing avalanches in order to represent the flow numerically by computer program AVALNCH. Nominal values of these parameters are determined to be in the range 0.4 to 0.6 for, snow flowing on snow, with values as high as 0.8 to 0.9 for snow flowing on rough ground. Using a nominal avalanche path, the basic parameters: (1) depth of initial release slab, (2) viscosity and friction, (3) adverse grade, and (4) flow spreading are determined to be in the order listed as regards their relative effect on avalanche runout distance. Program AVALNCH, which permits treatment of flow parameters separately from geometric parameters, provides a versatile tool for the prediction of avalanche runout, as well as for related studies of avalanche dynamics.