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Associate Prof. Takuya Tsuji

Department of Mechanical Engineering  Osaka University

tak@mech.eng.osaka-u.ac.jp

Takuya Tsuji received Ph.D in Engineering from Kyushu University in 2004 and has started his faculty career as an assistant professor in Osaka University. He became a research associate professor in 2009. Since 2012, He is an associate professor in the department of mechanical engineering, Osaka University. During 2015/5-2015/9, he was a guest professor in Swiss federal institute of technology Zurich. He has more than 50 publications in peer-reviewed journals in physics and engineering and received 13 awards including SPTJ best paper award in 2011 (The Society for Powder Technology, Japan), Frontier Award in 2015 (Fluid and Particle Processing Division, The Society of Chemical Engineers, Japan), and Frontier award in 2021 (Fluids Engineering Division, Japan Society of Mechanical Engineers). He served as an editor of Advanced Powder Technology journal. He is interested in the numerical modeling and physical elucidation of dense gas-solid, liquid-solid, gas-liquid-solid flows in addition to granular flows.

Title: Density segregation of granular materials in vibrated gas-fluidized bed (coarse-graining DEM-CFD and experimental investigations)

Abstract: Density segregations of binary particles in a vibrated fluidized bed are investigated numerically and experimentally. A numerical model is constructed by coupling the discrete element method (DEM) with the computational fluid dynamics (CFD) in a non-inertial frame of reference. An upscaled coarse-graining model is employed to prevent the large computational cost of DEMCFD. After the validation study of the model, the change of segregation behaviors depending on gas inflow velocity is investigated. A sudden change from reverse to forward segregation observed experimentally is reasonably captured numerically, and its physical mechanism is discussed in detail. In addition to the positive gas pressure gradient in the vertical direction, the particle transportation to the bed bottom induced by the wall friction plays a major role in the segregation.