Hans Herrmann
Institute for Building Materials, ETH Zurich, Switzerland
Date
27 February 2008
Title
The Physics of Dunes
Abstract
Dunes are aerodynamic instabilites that exist in deserts and along coasts. I will present the first set of equations of motions that correctly describes the evolution of a free granular surface under the action of wind and gravity. These equations do indeed reproduce measured dunes quantitatively as has been verified in Marocco and Brazil. The collision of dunes can show solitary wave character or breeding of baby dunes. Adding a further equation for vegetation growth one can study dune fixation and the transition to parabolic dunes. It is also possible to reproduce dunes on Mars explaining their strange shape and getting insight about the local saltation process.