Research
Mesoscopic numerical simulation of dense gas-solid flows by DEM-CFD coupling model
Dense gas-solid flows that include the mixture of gas and dense solid particles occur ubiquitously in nature and in industrial systems. Typical examle is fluidized beds used for processes like combustion, gasification, granulation, coating, catalysis and so on. Due to the strong interactions between particle - particle/wall in addition to particle - gas flows, its behavior is quite complex. Due to the existance of highly-concentrated solid particles, optical measurement techniques do not make sense in the major cases. Reliable numerical technique which enables us to observe internal flow structures in detail has been highly desired. Since the pioneering work by Tsuji, Kawaguchi & Tanaka, "Discrete particle Simulation of two-dimensional fluidized bed", Powder Technology, 77, 79–87, (1993), we keep on working with DEM-CFD coupling models and several model improvements including parallelization for large-scale calculations and model extensions to include heat and mass transfers, particle level forces such as liquid bridge force have been performed.
Numerical simulation of large object motions in dense gas-solid flows
In practical flow applications including dense solids such as fluidized beds and pneumatic conveyers, the size of solid materials is not uniform and large solids are coexisting with small solids. The large size difference induces characteristic motion of solids and results in segregation phenomena. It is difficult to predict and reproduce the behaviour of these systems by existing numerical models and a new numerical model named "Fictitious particle model" is proposed.
Resolved direct numerical simulation of flows including dense solid particles
Excavation simulation by DEM
Application of Magnetic Resonance Imaging (MRI) to granular flows
Keywords
Gas-solid two-phase flows, Particle-laden flows, Discrete Element method (DEM), DEM-CFD coupling method, Direct numerical simulation, Contact force model, Fluidized bed, Granulation, Terramechanics, Liquid brige force, Meso-scale structure