Avalanche study goes with the flow

An installation that uses fluid mechanics to generate avalanches in the laboratory has been developed to help scientists better understand the physical mechanisms of the phenomena.

Computer models simulating complex fluid movement, such as those found in avalanches, are often used, but these are still quite rudimentary.

The laboratory-based system, which was developed at the Federal Institute of Technology in Lausanne by rheology expert Prof Christophe Ancey and his team, is based on the ‘dam-break’ concept, in which a viscous fluid is poured on to a steeply inclined plane.

The blue liquid (pictured below) flowing down the slope deforms in the same way an avalanche does, as it shares the same highly complex, non-linear flow characteristics of heavy snow and mud.

Unlike natural avalanches, all the variables involved in Ancey’s experiments can be controlled so that the same avalanche can be studied repeatedly.

The data will be used to build a numerical model describing an avalanche’s dynamic behaviour, which will be tested at a measurement station that has been set up in the Swiss Alps.

As an avalanche moves down the mountain, equipment placed in its track — including a bunker equipped with a variety of sensors, video and Doppler radar — will collect data.

Ancey’s model will predict the avalanche’s progression, and comparison with real avalanche data will reveal how well his model captured events.