Dense snow flowing past a deflecting obstacle: An experimental investigation

Dense snow flowing down a rough inclined chute and interacting with a deflecting obstacle is experimentally investigated. These experiments are of considerable practical interest for the design of deflecting dams that are built to defend against large-scale snow avalanches. Our study focused on the maximum run-up reached by the dense flowing snow on a deflector. It was found that the maximum run-up was strongly correlated to the upstream Froude number and the deflecting angle of the obstacle. The data was compared with the predictions from a simple conversion of kinetic energy to potential energy on one hand and with oblique shock calculations on the other hand. The predicted values from the first approach were in better agreement with the measured values in comparison with the second approach. During a short transient phase at the end of the flow, it was shown that the flow features from our snow experiments were identical to the flow features from the previous granular and water experiments. In these conditions, the shallow-layer theory was also found to be relevant for snow flows.