Numerical investigation of the pebble bed structures for HCCB TBM

Gong, Baoping; Feng, Yongjin; Liao, Hongbin; Wang, Suhao; Feng, Kai-Ming

doi:10.1016/j.fusengdes.2018.05.033

Cited by 29 publications

(9 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When the distance between two pebble centers is smaller than the sum of the radii touch distance (R i + R j ), the contact force and the friction action are evaluated based on the Hertz-Mindlin [61,62] theory and Coulomb friction criterion. The detailed theory of DEM can be found in the literature [7,8,55,62].…”

Section: Simulation Methods and Parametersmentioning

confidence: 99%

“…In this study, LIGGGHTS-PUBLIC [61] was employed. The pebble parameters used in this study are listed in Table 1 by referring to the parameters of the Li 4 SiO 4 ceramic pebbles in the literature [7,8,11,31]. The heights of all pebble beds are higher than 60 mm.…”

Section: Simulation Methods and Parametersmentioning

confidence: 99%

“…Taking a rectangular pebble Figure 7 shows that when the cross-sectional area is fixed, the D e of the rectangular tubes decreases gradually with the increase in the aspect ratio α of the rectangular tubes, which might be the reason that the γ avg of the rectangular pebble bed decreases gradually with the increase in aspect ratio α. Such as, the γ avg also increases with the increase in the ratios of cylinder diameter to pebble diameter for the cylindrical pebble beds [8] and the ratios of the side length to pebble diameter for the square pebble beds [7,8], respectively. Similarly, Figure 7d shows the variation in the γ avg of the pebble bed with the D e of the rectangular tubes with the different cross-sectional areas.…”

Section: Effect Of the Aspect Ratio Of Rectangular Tubementioning

confidence: 98%

“…In nuclear energy systems, the core system of a hightemperature gas-cooled reactor is a cylindrical pebble-bed assembly packed with spherical fuel particles [2][3][4]. For a fusion energy reactor, the tritium breeder and neutron multiplier pebbles are packed in rectangular [5], U-shaped [6][7][8], or cylindrical vessels in blanket modules [9][10][11]. In addition, pebble packings are also widely used in some other fields, such as 3D-printing processes [12], pellet sandpiles [13], the packing and combustion processes of biomass fuel particles [14], storage of grain particles [15], solar energy storage systems [16], etc.…”

Section: Introductionmentioning

confidence: 99%

“…Several equations were also proposed to predict the local porosity distributions in three defined zones in a square pebble bed. Gong et al [7,8,32] and Taguchi et al [48] investigated the packing fraction and the local porosity distribution in cylindrical and cubic pebble beds. A similar porosity distribution was obtained in a cubic pebble bed.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Effects of the Aspect Ratio and Cross-Sectional Area of Rectangular Tubes on Packing Characteristics of Mono-Sized Pebble Beds

et al. 2023

Self Cite

View full text Add to dashboard Cite

The packing characteristics of a pebble bed are essential to understand the heat- and mass-transfer processes occurring within a granular system. Therefore, the packing characteristics of rectangular prismatic pebble beds randomly packed with mono-sized pebbles are analyzed. In terms of the average and local packing fraction distribution, coordination number, and radial distribution function, the effects of the rectangular tube aspect ratio and cross-sectional area on the packing properties of pebble beds are explored in depth. The findings indicate that the packing structures of the rectangular pebble bed exhibit noticeable fixed-wall effects. The average packing fraction and coordination number gradually decline as the rectangular tube aspect ratio rises. Close to the fixed wall, a noticeable wall effect can be seen in the distribution of axial and local packing fractions and the pebble center distribution. The wall effect has an increasing effect on the axial and local packing fraction distributions in rectangular tubes with increasing aspect ratios. Additionally, the average packing fraction and the average coordination number also increase as the cross-sectional area increases, indicating a gradual weakening of the wall effect as the cross-sectional area increases. Furthermore, the cross-sectional area and aspect ratio of the rectangular tubes affect the RDF values of the rectangular pebble beds but have no impact on the RDF features. The findings reported in this paper will be helpful for designing and optimizing pebble beds in the breeding blanket of fusion reactors.

show abstract