Dynamic vertical forces working on a large object floating in gas-fluidized bed: Discrete particle simulation and Lagrangian measurement

Non-invasive measurement of floating–sinking motion of a large object in a gas–solid fluidized bed

“…The upward force acting on the object also varies periodically and it shows a "γ"-shaped change. In our previous study [13], the floating motion of the object is characterized by three stages. In the first stage, the bed expands due to a rising bubble and the floating object moves upward with the motion of the free surface.…”

“…The upward force acting on the object is obviously the combination of the contact force with fluidized particles and the fluid force in this case. In our previous study, the contribution of the contact and fluid forces acting on the object in the fluidized bed was examined by discrete particle simulation [13,26]. The simulation results indicated that the fluid force is much more significant than the contact force except for the final impulsive stage.…”

“…In the previous study, we developed a non-invasive measurement system for detecting the dynamic force acting on a spherical object moving freely in a fluid flow [7,13]. This system consists of MEMS sensors, a data processing IC and a wireless module for data transmission.…”

Non-intrusive measurement and hydrodynamics characterization of gas–solid fluidized beds: a review

“…At the current stage, a wide variety of sensors applied on gas-solid fluidized beds allow the measurement of solids/particle velocity, particle size, particle trajectory, For instance, a Lagrangian sensor system, mainly composed of an accelerometer, a magnetometer, a microcomputer and a wireless transmitter module, has recently been developed to measure the forces on a free-moving object in a bubbling fluidized bed [229]. The Lorentz force velocimetry, based on exposing the fluid under test to a magnetic field and measuring the drag force acting upon the magnetic field lines [230,231], has now been applied to weakly conducting fluids for the measurement of velocity and flow rate [232,233].…”

Coupling CFD-DEM with dynamic meshing: A new approach for fluid-structure interaction in particle-fluid flows

“…The solidity of immersed object is approximated by means of permeability controlled by input parameters of fictitious particle diameter and solid volume fraction inside the object. Although the flow at the bodies boundary is not fully resolved, experimental validation showed good agreements on the position of a free-moving large sphere during and after stopping the fluidization [33,34]. Its applicability for more complex geometries is not clear, and additional computational costs will be required for complex geometries in order to identify those computational cells containing the solid structure.…”