Analyzing dominant particle-flow structures inside a bubbling fluidized bed using POD

2018 ◽  
Author(s):  
Mohammad Reza Haghgoo ◽  
Donald J. Bergstrom ◽  
Raymond J. Spiteri
Keyword(s):  
Fluidized Bed ◽  
Particle Flow ◽  
Flow Structures ◽  
Bubbling Fluidized Bed

Analyzing dominant particle-flow structures inside a bubbling fluidized bed

2019 ◽  
Vol 77 ◽  
pp. 232-241
Author(s):  
Mohammad Reza Haghgoo ◽  
Donald J. Bergstrom ◽  
Raymond J. Spiteri
Keyword(s):  
Fluidized Bed ◽  
Particle Flow ◽  
Flow Structures ◽  
Bubbling Fluidized Bed

Investigating the flow structures in semi-cylindrical bubbling fluidized bed using pressure fluctuation signals

2019 ◽  
Vol 30 (6) ◽  
pp. 1247-1256
Author(s):  
Seyedeh Mahsa Okhovat-Alavian ◽  
Jamshid Behin ◽  
Navid Mostoufi
Keyword(s):  
Fluidized Bed ◽  
Pressure Fluctuation ◽  
Flow Structures ◽  
Bubbling Fluidized Bed

Gas-Mixing in Bubbling Fluidized Bed Combustors: Hydrodynamics and Macromixing Associated With Bubble Bursting at the Bed Surface

2003 ◽  
Author(s):  
R. Solimene ◽  
A. Marzocchella ◽  
P. Salatino ◽  
R. Ragucci
Keyword(s):  
Fluidized Bed ◽  
Fluid Dynamic ◽  
Volatile Matter ◽  
Solid Fuels ◽  
Flow Structures ◽  
Specific Reference ◽  
Gas Mixing ◽  
Fluidized Bed Combustion ◽  
Bubble Bursting ◽  
Bubbling Fluidized Bed

Gas-mixing phenomena may play a significant role in fluidized bed combustion of solid fuels. Issues associated with gas mixing include: a) effectiveness of mass transfer between the bubble and the emulsion phases in the bed; b) degree of mixing between segregated gaseous streams in plume-like or bubbly flow in the bottom bed; c) extent of mixing between segregated gaseous pockets/streams in the splashing zone or in the upper freeboard. Among the others, issues b) and c) turn out to be relevant to fluidized bed combustion of high-volatile solid fuels (biomass, RDF, etc.). In this case, the rate of gas mixing often overcomes intrinsic kinetics as the rate-controlling step in volatile matter burn-out, especially under “stratified” combustion conditions. Despite several and significant contributions to the subject, understanding of gas-mixing in bubbling fluidized beds is still poor and calls for additional investigation. The present work aims at investigating gas-mixing in bubbling fluidized bed with specific reference to the above issue c). A laser assisted imaging technique has been used to characterize the hydrodynamic patterns associated with the bursting of either isolated bubbles or couples of closely time-delayed bubbles at the surface of a fluidized bed. Quantitative image analysis procedures were exploited in order to assess parameters defining the general fluid-dynamic behaviour and macromixing of the bubble-generated gas pockets with the mainstream gas. The formation of toroidal flow structures upon bubble bursting is highlighted in the case of isolated bubbles. The toroidal pockets entrain mainstream gas and grow accordingly while rising along the splash zone. Toroidal flow structures are observed also in the case of couples of closely time-delayed bubbles, but interference between leading and trailing pockets leads to more complex structures characterized by multiple incoherent eddies. The relevance of macromixing to volatile matter burning under conditions of stratified fluidized bed combustion is assessed and discussed.

Numerical Simulation of Dual-Support Leg Fluidized Bed

2011 ◽  
Vol 347-353 ◽  
pp. 627-630
Author(s):  
Qin Liang Tan ◽  
Tian Liu ◽  
Da Long Jiang ◽  
Xiao Ying Hu ◽  
Chang Qing Dong
Keyword(s):  
Fluidized Bed ◽  
Granular Flow ◽  
Numerical Study ◽  
Particle Flow ◽  
Flow Structures ◽  
Solid Model ◽  
Motion Trajectory ◽  
Upward Flow ◽  
Flow Mechanisms ◽  
Support Leg

A numerical study on a gas-solid model to predict the particle flow structures of dual support-leg fluidized bed has been conducted. Due to the symmetry motion trajectory of the particles in the dual support-leg fluidized bed, unilateral furnace was taken into account in the model to simplify calculation. The results indicate that, without buffer set on the wall, three different zones can be distinguished in terms of granular flow mechanisms. The velocities of the upward flow without buffer set on the wall are much higher than that with buffer set.

Tar formation during eucalyptus gasification in a bubbling fluidized bed reactor: Effect of feedstock and reactor bed composition

2021 ◽  
Vol 229 ◽  
pp. 113749
Author(s):  
D.T. Pio ◽  
L.C.M. Ruivo ◽  
L.A.C. Tarelho ◽  
J.R. Frade ◽  
E. Kantarelis ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Bubbling Fluidized Bed

Simulation of biomass gasification in bubbling fluidized bed reactor using aspen plus®

2021 ◽  
Vol 235 ◽  
pp. 113981
Author(s):  
M. Puig-Gamero ◽  
D.T. Pio ◽  
L.A.C. Tarelho ◽  
P. Sánchez ◽  
L. Sanchez-Silva
Keyword(s):  
Fluidized Bed ◽  
Aspen Plus ◽  
Fluidized Bed Reactor ◽  
Biomass Gasification ◽  
Bubbling Fluidized Bed
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