%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Montserrat, S.
%A Ordonez, L.
%A Tamburrino, A.
%A Roche, Olivier
%T Influence of bottom roughness and ambient pressure conditions on the emplacement of experimental dam-break granular flows
%D 2021
%L fdi:010081462
%G ENG
%J Granular Matter
%@ 1434-5021
%K Dam-break ; Granular flows ; Pore pressure ; Ambient pressure ; Fluidization ; Substrate roughness
%M ISI:000651817700001
%N 3
%P 57 [8 ]
%R 10.1007/s10035-021-01125-2
%U https://www.documentation.ird.fr/hor/fdi:010081462
%> https://www.documentation.ird.fr/intranet/publi/2021-06/010081462.pdf
%V 23
%W Horizon (IRD)
%X Geophysical granular flows occur at the surface of the Earth and other planets with reduced atmospheric pressure. In this paper, we investigate the run-out of dam-break flows of particle-air mixtures with fine (d = 75 mu m) or coarse (d = 150 mu m) grains in a flume with different bottom roughness (delta) and vacuum degrees (P*). Our results reveal an increase of the flow run-out as d/delta decreases for fine d = 75 mu m-particles, and run-out decreases with the dimensionless ambient pressure (P*) for a given d/delta. In contrast, the run-out for coarser d = 150 mu m-particles, is almost invariant respect to P* and d/delta. These results show that autofluidization of fine-grained flows demonstrated by earlier works at ambient pressure also occurs at reduced pressure though being less efficient. Hence, autofluidization is a mechanism, among others, to explain long run-out of geophysical flows in different environments.
%$ 064 ; 020