[Détermination expérimentale de la densité de probabilité de concentration d'une couche de particules en saltation]
La dispersion de particules de verre en mouvement de saltation à l'intérieur d'une couche limite turbulente est étudiée expérimentalement. Les concentrations ont été déterminées par diffusion de la lumière et analyse d'images. Certaines caractéristiques statistiques ont été mesurées telles les concentrations moyennes, les différents moments statistiques ainsi que les densités de probabilité. Les résultats expérimentaux confirment que la concentration moyenne décroît exponentiellement avec la hauteur, la hauteur moyenne de dispersion eulérienne H étant une échelle de longueur caractéristique. On montre en plus que la distribution de concentration instantanée est une variable aléatoire qui suit une loi de distribution Lognormale.
A horizontal saltation layer of glass particles in air was investigated experimentally in a wind tunnel. Particle concentrations are measured by light scattering diffusion and image processing and all the statistical characteristics were evaluated and thus the probability density function. Our experimental results confirm that the mean concentration decreases exponentially with height, the mean Eulerian dispersion height H being a characteristic lengthscale and that the instantaneous concentration distribution is a random variable following quite well a lognormal distribution.
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Mot clés : Milieux granulaires, Turbulence, Saltation, Dispersion, Particules solides
XiaoHang Zhang 1, 2 ; HongTao Wang 3 ; ZhiBao Dong 3 ; Michel Ayrault 2
@article{CRMECA_2006__334_1_13_0, author = {XiaoHang Zhang and HongTao Wang and ZhiBao Dong and Michel Ayrault}, title = {Experimental determination of the concentration {Probability} {Density} {Function} for a saltating particle layer}, journal = {Comptes Rendus. M\'ecanique}, pages = {13--18}, publisher = {Elsevier}, volume = {334}, number = {1}, year = {2006}, doi = {10.1016/j.crme.2005.10.017}, language = {en}, }
TY - JOUR AU - XiaoHang Zhang AU - HongTao Wang AU - ZhiBao Dong AU - Michel Ayrault TI - Experimental determination of the concentration Probability Density Function for a saltating particle layer JO - Comptes Rendus. Mécanique PY - 2006 SP - 13 EP - 18 VL - 334 IS - 1 PB - Elsevier DO - 10.1016/j.crme.2005.10.017 LA - en ID - CRMECA_2006__334_1_13_0 ER -
%0 Journal Article %A XiaoHang Zhang %A HongTao Wang %A ZhiBao Dong %A Michel Ayrault %T Experimental determination of the concentration Probability Density Function for a saltating particle layer %J Comptes Rendus. Mécanique %D 2006 %P 13-18 %V 334 %N 1 %I Elsevier %R 10.1016/j.crme.2005.10.017 %G en %F CRMECA_2006__334_1_13_0
XiaoHang Zhang; HongTao Wang; ZhiBao Dong; Michel Ayrault. Experimental determination of the concentration Probability Density Function for a saltating particle layer. Comptes Rendus. Mécanique, Volume 334 (2006) no. 1, pp. 13-18. doi : 10.1016/j.crme.2005.10.017. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2005.10.017/
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