Experimental evidence of granulence
Författare
Summary, in English
We present an experimental study of velocity fluctuations in quasistatic flow of a 2D granular material deformed in a shear apparatus named 1γ2ε [1]. Radjaï and Roux [2] revealed systematic similarities between velocity fluctuations observed in discrete element simulations of quasistatic flow of granular material and turbulent flows in fluids. The character of these velocity fluctuations - named granulence by [2] - manifests as a non-Gaussian broadening of the probability density function of the fluctuations as the length of the analyzed shear-window is decreased, and exhibits some space and time scaling. The experiments presented are simple shear tests on granular samples composed of about 2000 wooden rods. The kinematics of the rod centers was followed by means of 2D Particle Image Tracking (PIT) technique applied to a sequence of 24 Mpixels digital pictures acquired throughout the duration of the loading at a frequency of 0.08 image/s. This analysis confirms the existence of granulence features in a real experimental test, which is comparable to that previously observed in numerical simulations of [2]. The experimental results obtained open up a new avenue for further studies on fluctuations in granular materials.
Publiceringsår
2013
Språk
Engelska
Sidor
453-456
Publikation/Tidskrift/Serie
AIP Conference Proceedings
Volym
1542
Dokumenttyp
Konferensbidrag
Ämne
- Mechanical Engineering
Status
Published