Particle deposition and resuspension in gas-cooled reactors—Activity overview of the two European research projects THINS and ARCHER

Barth, Tarik; Lecrivain, Gregory; Jayaraju, Santhosh; Hampel, Uwe

doi:10.1016/j.nucengdes.2014.11.047

Cited by 9 publications

(3 citation statements)

References 61 publications

(98 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Barth et al (2014) conducted experimental tests to investigate particle resuspension in a horizontal turbulent channel flow at Reb=8900 and found that particle resuspension occurs when the fluid friction velocity reaches a critical level, with lower fluid velocities required by large particles than by small particles. In 2015, they further investigated particle deposition and resuspension behavior in gas-cooled reactors (Barth et al 2015). In addition, Afkhami et al (2014Afkhami et al ( , 2015 employed LES and the discrete element method to study particle dispersion and agglomeration behavior in a horizontal channel flow and concluded that both particle-particle interactions and Reynolds number have a significant effect on these particle behaviors across the flow Reb range considered (2100-8260).…”

Section: Introductionmentioning

confidence: 99%

Reynolds number dependence of particle resuspension in turbulent duct flows

Zhao

Wang

et al. 2018

Chemical Engineering Science

View full text Add to dashboard Cite

Particle resuspension in a fully developed turbulent square duct flow is simulated using oneway coupled large eddy simulation coupled with a Lagrangian particle tracking technique for a range of bulk Reynolds numbers (36.5k, 83k and 250k) and four particle sizes ranging from 5 to 500 m (St=0.01~2415) considered. Results obtained for the single-phase flow show good agreement with experimental data. Predictions of the time-dependent particle-laden flows demonstrate that the secondary flow mainly dominates particle resuspension in the regions near the center and sidewalls of the duct. It is found that particle resuspension decreases with particle size. The smaller particles tend to be more prone to resuspension, and are resuspended for a longer duration than larger particles. The mean particle resuspension velocity is found to increase with the duct height. In addition, particle resuspension in the vertical direction increases with Reynolds number while the effect of particle size on particle resuspension decreases. The resuspension rate in the spanwise direction fluctuates more as the Reynolds number increases. It is also found that the average particle resuspension rate in the lower half of the duct is always close to 0.5, and is independent of time, particle size and Reynolds number. Based on a dynamic analysis, the drag force is found to dominate the resuspension of small particles, while the lift force tends to dominate particle resuspension with increasing particle size. For low Reynolds number (36.5k and 83k) flows, the drag force plays an important role in the upper regions of the lower half of the duct, but the lift force dominates particle behaviour in the lower regions. It can be concluded that the effects of duct height on particle behaviour decline significantly with Reynolds number.

show abstract

Section: Introductionmentioning

confidence: 99%

Reynolds number dependence of particle resuspension in turbulent duct flows

Zhao

Wang

et al. 2018

Chemical Engineering Science

View full text Add to dashboard Cite

show abstract

“…It is important to remember that the circularity of all these particles is constant and obviously equal to 1. It is also important to say that other experimental and numerical results have shown this same feature of decreasing shearing stress for the removing of larger particles when spherical geometry is considered [63]. Nevertheless, little is known for other geometries.…”

Section: Case Amentioning

confidence: 74%

Kinetic Monte Carlo method applied to micrometric particle detachment mechanisms by aerodynamic forces

Olivares¹,

Benito²,

Uñac³

et al. 2021

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The formulation of a kinetic Monte Carlo simulation to account for the different possible mechanisms present in the problem of resuspension of aerosol particles is addressed as an extension of a former model Benito et al (2016 J. Aerosol Sci. 100 26–37). The re-entrainment of micrometer particles to airflow when detached from a surface by aerodynamic forces is modeled using the similitude of the problem with the desorption process from heterogeneous surfaces. Depending on the relative role of the intervening forces, three main mechanisms for movement initiation can be present: rolling, sliding and lifting-off. Three different transition probabilities are defined for each mechanism and the corresponding transition rates calculated for the kinetic process to be simulated. The decisive factor for the development of the model is to set an appropriate dynamical hierarchy to simulate correctly the evolution of the transition rates as the airflow velocity increases, reflecting the stochastic nature of the process, not always fully captured by other Monte Carlo approaches. The model is applied to spherical and elongated particles on a flat surface, reproducing qualitatively well the experimental trends found by other authors for the case of particles with different shapes. It is also demonstrated that, for elongated particles, the main mechanism assisting the detachment is not rolling but sliding, underscoring the need for an adequate choice of the particles shape and detachment mechanism when looking for the critical conditions for particle removal from surfaces.

show abstract

“…Shields [4] pioneered the field by reporting the existence of a threshold friction velocity beyond which resuspension occurs. Multiple empirical studies have since been performed and various estimates of this threshold friction velocity are now available [5,6]. Since then, a number of experimental and numerical studies have investigated particle resuspension, usually making a distinction between monolayer and multilayer deposits.…”

mentioning

confidence: 99%