We have used special parameters in the input file cas which contains what needed for beginning the Telemac application in order to approach the physical phenomenon at best. Indeed Telemac solves the Saint-Venant equations for free-surface flow with low slopes so it is, at first sight, not very well adapted to our case.
Here is detailled the different parameters we changed compared to an usual Telemac application.
  • Numerical parameters
  • We have used the indications given by the previous studies on Rupture de Barrage which can be compared to the flow of a wet snow avalanche.
    For the type of advection, we used the option schema conservatif + option de SUPG. And the SUPG method is a decentrement amont egal au nombre de courant.

  • Bottom friction
  • We used a Strikler model for the law of bottom friction and a low value of the friction coefficient chosen equal first to 12 and then to 5, which represents a non physical value of this parameter which is usually between 25 and 100. Indeed in theory we should have taken a threshold friction in order to visualize the stopping zone which is impossible with the water flow of Telemac. In consequence, we decided to take a very rough bottom in order to slow down as much as possible the avalanche.

  • Turbulence term
  • Concerning the term of turbulence rubbing in U^2 in the equations, Telemac doesn't take it into account so the simulations have been run without this term.
    There is perhaps a possibility to impose a forcing term in Telemac to modelise the wind effects but to adapt it to our study we would have needed more time. Indeed it is necessary to write a subroutine to calculate the term value at every time step to use it into the next time step.