Title RAMMS; numerical simulation of dense snow avalanches in three-dimensional terrain
Author Christen, M.; Kowalski, J.; Bartelt, P.
Author Affil Christen, M., Institute for Snow and Avalanche Research, Davos, Switzerland
Source Cold Regions Science and Technology, 63(1-2), p.1-14, . Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0165- 232X
Publication Date Aug. 2010
Notes In English. Based on Publisher- supplied data GeoRef Acc. No: 309535
Index Terms avalanche mechanics; avalanches; density (mass/volume); mass movements (geology); rheology; simulation; snow; density; equations; mass movements; numerical models; RAMMS; three-dimensional models; transport
Abstract Numerical avalanche dynamics models have become an essential part of snow engineering. Coupled with field observations and historical records, they are especially helpful in understanding avalanche flow in complex terrain. However, their application poses several new challenges to avalanche engineers. A detailed understanding of the avalanche phenomena is required to construct hazard scenarios which involve the careful specification of initial conditions (release zone location and dimensions) and definition of appropriate friction parameters. The interpretation of simulation results requires an understanding of the numerical solution schemes and easy to use visualization tools. We discuss these problems by presenting the computer model RAMMS, which was specially designed by the SLF as a practical tool for avalanche engineers. RAMMS solves the depth- averaged equations governing avalanche flow with accurate second-order numerical solution schemes. The model allows the specification of multiple release zones in three- dimensional terrain. Snow cover entrainment is considered. Furthermore, two different flow rheologies can be applied: the standard Voellmy-Salm (VS) approach or a random kinetic energy (RKE) model, which accounts for the random motion and inelastic interaction between snow granules. We present the governing differential equations, highlight some of the input and output features of RAMMS and then apply the models with entrainment to simulate two well- documented avalanche events recorded at the Vallee de la Sionne test site.
URL http://hdl.handle.net/10.1016/j.coldregions.2010.04.005
Publication Type journal article
Record ID 65006572