Hydrodynamic and Heat Transfer Study of a Fluidized Bed by Discrete Particle Simulations

Mu, L.; Buist, Kay A.; Kuipers, J.A.M.; Deen, NG Niels

doi:10.3390/pr8040463

Cited by 14 publications

(7 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This mixing behavior can be analyzed through qualitative results of solid-phase distribution contours in Figures 9A-2, A-3. This behavior is also depicted by Mu et al (2020), where the solids have a higher velocity at the annular region when using low superficial gas velocities. However, as the fluidization velocity of air increased, the velocity profile of solids shifted toward the central core of the bed.…”

Section: Mixing Behavior Of Solid Particlesmentioning

confidence: 70%

Computational Analysis of the Hydrodynamic Behavior for Different Air Distributor Designs of Fluidized Bed Gasifier

et al. 2021

View full text Add to dashboard Cite

Fluidized bed gasification has proven to be an appropriate technique for converting various biomass feedstocks into helpful energy. Air distributor plate design is one of the critical factors affecting the thermochemical conversion performance of fluidized bed gasifiers. The present study is proposed to investigate the mixing pattern and pressure drop across different configurations of air distributors using a two-fluid model (TFM) of finite volume method-based solver ANSYS FLUENT. The pressure drop across the bed and mixing pattern have been investigated through qualitative and quantitative analysis of CFD results using three diverse distributor plate designs: perforated plate, 90° slotted plate, and 45° swirling slotted plate. The pressure drop by employing the perforated distributor plate reveals the highest pressure drop due to the smallest open area ratio. However, the pressure drop in the case of 90° slotted plate is found to be 7% and 4% lesser than perforated and 45° slotted plate respectively due to a smaller velocity head developed through the wider open area of the straight slotted plates. The distributor design configuration having a 45° slotted plate exhibits considerable pressure drop compared to the 90° slotted plate due to the longer path length of the slot. Numerical pressure drop results across the bed with different types of distributor plates prove reasonable agreement with the experimental results available in the literature. Mixing behavior in perforated distributor plates exhibits lower portion solid volume fraction of around 0.58. However, it falls rapidly as go up the riser (7.7% of column height); 90° slotted plate shows bottom region solid volume fraction of around 0.5. In addition, it exhibits an even broader range of sand volume fraction and column height (13.46% of column height). Finally, the 45° distributor plate reveals the highest range of volume fraction through the riser height (17.3% of column height), indicating the better mixing characteristics of the fluidized zone.

show abstract

Section: Mixing Behavior Of Solid Particlesmentioning

confidence: 70%

Computational Analysis of the Hydrodynamic Behavior for Different Air Distributor Designs of Fluidized Bed Gasifier

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Some applications include polymerization in producing polyethylene, fluid catalytic cracking, and fluidized bed coal combustion. A simulation study by [11] utilized a fluidized bed to investigate the hydrodynamics and heat transfer employing a computational fluid dynamics-discrete element method. Analysis was conducted on how the fluidized bed's hydrodynamics and thermal behavior were affected by the gas superficial velocity and bed aspect ratio.…”

Section: Fluidized Bedmentioning

confidence: 99%

Recent Advances in Particle Fluidization

Balag,

Franco,

Miral

et al. 2023

Asec 2023

View full text Add to dashboard Cite

show abstract

“…To understand the role of mass and heat transfer in the efficiency of fluidised beds, it is essential to consider the critical variables of pressure drop, temperature, bed height, superficial velocity, flow rate, and minimum fluidisation velocity. Whilst there is a body of research that has studied the use of Eulerian-Eulerian granular models or Eulerian models coupled with the discrete element method (DEM) for such applications, such studies [37,38,39,40,41,42] typically focused on the temperature and voidage in the bed. Thus, this paper aimed at filling the gap in literature on the use of such a model to:…”

Section: Introductionmentioning

confidence: 99%

Modelling of a Heated Gas-solid Fluidised Bed using Eulerian Based Models

Potgieter

Bhamjee

Kruger

2021

rdj

View full text Add to dashboard Cite

An Eulerian-Eulerian granular model was used to simulate the flow and heat transfer through a heatedgassolid fluidised bed. The primary objective of the study was to determine whether the Eulerian-Eulerian granular model adequately predicts the chamber pressure drop, temperature, and bed expansion through the bed. The model predictions were assessed and validated for various flow-regimes, namely the fixed-bed, smooth, bubbling fluidisation, and the maximum fluidisation regimes. This was done on an experimental scale heated gas-solid fluidised bed. However, the results are generalisable for heated gas-solid fluidised beds when the flow is laminar. Numerical models were created using Computational Fluid Dynamics (CFD). The CFD-model predictions were investigated, analysed, and compared to experimental results. Basic experiments were carried out to obtain varying hydrodynamic characteristics. The results showed a slight overprediction of pressure drop and bed expansion, however, the results were still in close agreement with the experiment. In contrast, underprediction of chamber temperatures were obtained. Based on the results of this study, it is recommended that the Eulerian model be used to predict dynamic flow behaviour. Before minimum fluidisation, when in a fixed bed regime, pressure drop in the chamber increases with no increase in bed height. No visible bubbles were present in the fixed bed regime. When fluidisation has been reached, the bed height rises whereas the pressure drop tends to a constant value. Bubble size increases with chamber height and increased superficial velocities. Bubble speed increased with increased chamber height. With increased superficial velocity, the chamber temperatures increase to a maximum temperature of326.65 K with an initial heating element temperature of373.15 K. However, when excessive heat is present in the gas-solid fluidised bed, other methods that sufficiently incorporate particle-particle interactions and bubble-bubble interactions, are recommended. An investigation should be lent to bubble-bubble interactions in the fluidised beds with relation to heat transfer. Additional keywords: Heated fluidised bed, computational fluid dynamics, CFD, Eulerian, granular, fluidisation, gas-solid

show abstract

Hydrodynamic and Heat Transfer Study of a Fluidized Bed by Discrete Particle Simulations

Cited by 14 publications

References 16 publications

Computational Analysis of the Hydrodynamic Behavior for Different Air Distributor Designs of Fluidized Bed Gasifier

Computational Analysis of the Hydrodynamic Behavior for Different Air Distributor Designs of Fluidized Bed Gasifier

Recent Advances in Particle Fluidization

Modelling of a Heated Gas-solid Fluidised Bed using Eulerian Based Models

Contact Info

Product

Resources

About