This paper examines the roles that granular flow theory might play in the modeling the solid-phase stresses in fluidized beds. It begins with a discussion of the historical limiting cases of the quasistatic and rapid-flow regimes. It then reviews the elastic granular theories that unify those two regimes. Finally it shows that measurements of solid-phase pressures cannot be explained by commonl...

Gas fluidization is widely used in industries and has been extensively studied either experimentally or mathematically. Recently, the coupled approach of discrete particle simulation (DPS) for solid phase and computational fluid dynamics (CFD) for gas phase has been proposed to study the heat transfer in fluidized beds at a particle level. The approach offers a convenient way to study the effec...

Petri nets are frequently used for modeling and analysis of discrete event systems. Similar to other modeling formalisms for discrete systems, it suffers from state explosion. Fluidification can be used to overcome this difficulty yielding fluid approximation of original Petri nets in the sense of behaviours and properties. This models are called continuous Petri nets. In this work, stochastic ...

Fluidization of cohesive pharmaceutical powders is difficult to achieve and typically requires the introduction external forces. This study investigates fluidization fine inhalation grade lactose (size range from 0.1-20 μm) that are specifically developed for dry powder (DPI) applications. The behaviour was evaluated under six conditions: without aids, with only vertical vibration (VFA), a down...

This paper describes an experimental study on the extent of capture efficiency in a fluidized bed system under controlled conditions. Using aerosols as tracer compound, the capture efficiency in a fluidized bed was quantitatively measured as a function of contact distance (time). The paper presents the experimental technique as well as the results relating the capture efficiency to the bed hydr...

An experimental approach is proposed to investigate the gas-solid structure in the vicinity of a sparger nozzle in a fluidized bed. The local hydrodynamics were studied under injection velocities ranging between 0 and 100 m/s and three orientations. A fiber-optic probe was used to measure the instantaneous local particle holdup near the tip of the sparger nozzle. Under the investigated conditio...

The fluidization of certain biomasses used in thermal processes, such as sawdust, is particularly difficult due to their irregular shapes, varied sizes, and low densities, causing high minimum velocities (Umf). addition an inert material causes its Umf drop significantly. determination the binary mixture however hard obtain. Generally, predictive correlations are based on a small number specifi...

In this paper, experimental data on the drying kinetics of corn in a packed and fluidized bed are presented. Experimental research was conducted on a laboratory apparatus. Corn was used as a material because of its significance in agriculture and the food industry. An analysis of the influence of the operational parameters (the drying medium velocity i. e. the flu...

When discrete event systems are used to model systems with a large number of possible (reachable) states, many problems such as simulation, optimization, and control, may become computationally prohibitive because they require some enumeration of such states. A common way to effectively address this issue is fluidization. The goal of this paper is that of studying the effect of fluidization on ...

Introduction Understanding the jetting phenomena near the gas distributor plate in a fluidized bed is important to gassolids mixing, heat and mass transfer, and erosion on any bed internals, which can all affect the performance of the bed. Moreover, acoustic vibration in a fluidized bed can be used to enhance the fluidization quality of particulate matter. Visualizing the jetting structure usin...