Identify of flow patterns in bubbling fluidization

Li, Yuning; Fan, Hui; Fan, Xianfeng

doi:10.1016/j.ces.2014.07.012

Cited by 25 publications

(23 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note that although solid flow patterns are comparable to the observations reported in Li et al, the operating conditions and particle properties employed in this work are different. Li et al concluded that the solid flow patterns are dominated by various factors such as solid properties, superficial gas velocity, the pore size of the air distributor and H/D ratio.…”

Section: Resultssupporting

confidence: 72%

“…For spherical particles ( α = 1), solids move upwards to the bubble eruption zone through the central region and move downwards along the annulus. This is a typical bed behavior widely observed in BFB with spherical glass beads and also referred to as UCDW (upwards in the center of the bed, downwards near the wall) pattern or Type B flow pattern . Two circulation cells are observed within the whole bed, however, the circulation cells located at the bottom right and the top left at 4 U mf reform to nearly equal size at 6 U mf .…”

Section: Resultsmentioning

confidence: 69%

“…This flow pattern leads to intense particle‐particle interactions since at around H = 0.008–0.01 m and H = 0.008 and 0.018 m, the downward solid flow meets with the bottom solid up‐flow. Li et al studied different types of flow patterns in bubbling fluidization and reported this as a Type‐C flow pattern. At 6 U mf , four circulation cells are observed, two at the bottom and two at the top.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Bubble dynamics in bubbling fluidized beds of ellipsoidal particles

Shrestha

Kuang

et al. 2019

AIChE Journal

View full text Add to dashboard Cite

This article presents a CFD-DEM study on the effect of particle shape on bubble dynamics in bubbling fluidized beds. The particles used are ellipsoids, covering from disk-type to cylinder-type. The phenomena such as bubble coalescence and splitting are successfully generated, and the results are compared with literature, showing a good agreement. The results demonstrate that the bubble forming/rising regions and patterns are influenced significantly by particle shape. Ellipsoidal particles have asymmetrical bubble patterns with two or more circulation vortices while the bubbles for spherical particles form at the bed centerline and rise through the center of the bed. Hence, the vertical mass flux at the bed centerline for spheres is always positive, and ellipsoids have negative or positive vertical mass fluxes. The solid mixing estimated based on the dispersion coefficient revealed poor mixing for ellipsoids. Spherical particles have a larger bubble size and higher bubble rising velocity than ellipsoids.

show abstract

Section: Resultssupporting

confidence: 72%

Section: Resultsmentioning

confidence: 69%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Bubble dynamics in bubbling fluidized beds of ellipsoidal particles

Shrestha

Kuang

et al. 2019

AIChE Journal

View full text Add to dashboard Cite

show abstract

“…The positron emission particle tracking (PEPT) technique employs the radionuclide which decays via + decay and emits a positron as a tracer. The positron does not travel far but annihilates rapidly with an electron in its vicinity, producing a pair of 511 keV gamma-rays emitted almost back-to-back [188]. By detecting the two gamma-rays with two position-sensitive detectors, it is known that the positron-emitting particle should be somewhere on the line connecting the two gamma-rays.…”

Section: Positron Emission Particle Trackingmentioning

confidence: 99%

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

Sun

Yan

2016

Meas. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…This trend indicated that the gas velocity in the riser provided the momentum to the upward transportation of the solids, which, in turn, controlled the solids circulation between the riser and the bubbling bed. The flow pattern could directly affect the gas-solids mixing as well as heat and mass transfer in the bubbling bed [47]. Our previous studies have shown that the higher solids circulation rate produced a higher bed height and solids volume fraction, promoting the mixing of solids and gas in the bubbling bed [28].…”

Section: Effect Of Gas Velocity In the Risermentioning

confidence: 99%

Three-dimensional full loop simulation of solids circulation in an interconnected fluidized bed

et al. 2016

View full text Add to dashboard Cite

ReuseUnless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Abstract 3-D full loop CFD simulation of solids circulation rate is conducted in a complicated circulating-fluidized bed, which consists of a riser, a bubbling bed, a cyclone and a loop-seal. The effects of operating gas velocity, particle diameter and total solids inventory on the solids circulation rate are investigated based on the system pressure balance of an interconnected fluidized bed. CFD results indicate that the gas velocity in the riser plays a dominant role in controlling the solids circulation rate, whilst the gas velocity in the pot-seal influences in a narrow operating range. The solids circulation rate is strongly influenced by particle diameter and total solids inventory, but becomes insensitive to the operating conditions in the bubbling bed as the gas velocity is higher than the minimum fluidization velocity.

show abstract

Identify of flow patterns in bubbling fluidization

Cited by 25 publications

References 33 publications

Bubble dynamics in bubbling fluidized beds of ellipsoidal particles

Bubble dynamics in bubbling fluidized beds of ellipsoidal particles

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

Three-dimensional full loop simulation of solids circulation in an interconnected fluidized bed

Contact Info

Product

Resources

About