RAMMS

  • Increase font size
  • Default font size
  • Decrease font size
Error
  • Copy failed
Welcome, Guest
Username: Password: Remember me
Discussion about the friction parameters µ (Mu) and ξ (Xi).
  • Page:
  • 1

TOPIC: What are µ (Mu) and ξ (Xi)?

What are µ (Mu) and ξ (Xi)? 10 years 9 months ago #18

  • Yves
  • Yves's Avatar
  • OFFLINE
  • Administrator
  • Posts: 18
RAMMS employs a Voellmy-fluid friction model. This model divides the frictional resistance into two parts: a dry-Coulomb type friction (coefficient μ ) that scales with the normal stress and a velocity squared drag (coefficient ξ). The frictional resistance S (Pa) is then



where ρ is the flow density, g gravitational acceleration, φ the slope angle, H the flow height and U the flow velocity. This model has found wide application in the simulation of mass movements, especially snow avalanches. The Voellmy model has been in use in Switzerland for a long time and a set of calibrated parameters is available.
Dr. Yves Bühler
WSL Institute for Snow and Avalanche Research SLF
Avalanches, debris flows and rockfall research unit
Flüelastrasse 11 CH-7260 Davos Dorf
Tel: +41 81 4170 163
Fax: +41 81 4170 110
E.mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Last Edit: 10 years 9 months ago by nomad_12.
The administrator has disabled public write access.

Re:What are µ (Mu) and ξ (Xi)? 9 years 11 months ago #38

Hello,
I want to ask, if you can provide more informations about this two coefficients (Mu, Xi). I try to calibrate model for some case studies in High Tatra mountains in Slovakia, so I try to change values of this two coefficients.
Is there some theoretical background which deals about this friction coefficients (dry- Coulomb type friction and velocity squared drag)? Or how did you determine Friction Parameters Table, which is used in RAMMS model ?
I will be very appreciated for any informations about this.
Thank you very much for your answer,
yours sincerely

Jozef Richnavsky
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
The administrator has disabled public write access.
  • Page:
  • 1
Time to create page: 0.024 seconds

Affiliation

Banner
Banner

© SLF/WSL 2010