@article{fdi:010073172,
  title = {{E}xperimental measurement of the solid particle concentration in geophysical turbulent gas-particle mixtures},
  author = {{W}eit, {A}. and {R}oche, {O}livier and {D}ubois, {T}. and {M}anga, {M}.},
  editor = {},
  language = {{ENG}},
  abstract = {{D}ilute gas-particle mixtures in which the particles are carried by the turbulent fluid are found in various geophysical contexts, from cold snow avalanches to hot pyroclastic density currents. {T}hough previous studies suggest that such mixtures have maximum particle concentrations of a few volume percent, the dependence of this maximum concentration on the {R}eynolds number is unclear. {W}e addressed this issue through laboratory experiments in a vertical pipe, where dilute gas-particle mixtures were created by injecting a turbulent air flow from below. {N}early monodisperse mixtures of glass beads of different grain sizes (77 to 1,550m) were used with varying bulk concentrations from 0.025 to 8 vol. %. {T}o create quasi-static mixtures, the mean air velocity matched the terminal settling velocity for the grain sizes investigated. {T}he maximum {R}eynolds numbers of the mixtures were similar to 10(4)-10(6). {T}he air pressure indicated full support of the particle weight at concentrations down to 0.025 vol. %. {A}bove a critical particle concentration, at which all the particles were suspended, subsequent additional particles were not maintained in the mixture and led to the formation of clusters that settled downward in the pipe to form a dense fluidized bed. {M}aximum mean particle concentrations of the dilute mixtures increased from similar to 1 to similar to 2.8 vol. % and reached a plateau at increasing mixture {R}eynolds number. {T}hese results give insights into the maximum particle concentrations of geophysical turbulent gas-particle mixtures and may serve to constrain observations as well as the input and output data of models.},
  keywords = {gas-particle mixtures ; particle concentration ; cluster ; pyroclastic ; density currents ; volcanic plumes ; snow avalanches},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch : {S}olid {E}arth},
  volume = {123},
  numero = {5},
  pages = {3747--3761},
  ISSN = {2169-9313},
  year = {2018},
  DOI = {10.1029/2018jb015530},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073172},
}