Figure 1

Upper panel: The vertical position of the intruder, measured at the subsequent nodes of the oscillating box, as a function of ${\log }_{10}\left(ft\right)$, for a constant frequency $f=15\mathrm{Hz}$, and different values of acceleration. $1:\Gamma =1.75$, $2:\Gamma =1.8$, $3:\Gamma =1.85$, $4:\Gamma =1.9$, and $5:\Gamma =1.95$, $6:\Gamma =2.0$, $7:\Gamma =2.5$, and $8:\Gamma =3.0$. Inset, intruder time-average speed as a function of $\Gamma$, for the vault and convective regime, circles and triangles, respectively. Middle panel: the convection intensity $\Phi$, in the presence of the intruder, as a function of depth at several time stages $t_1–t_4,t_H$ corresponding to the time when the intruder reaches the free surface. Lower panel: convection intensity $\Phi$ in the absence of the intruder at the same time stages $t_1–t_4$.Reuse & Permissions

Figure 2

Snapshots of the convecting particles and intruder segregation at different times $t$. For $f=15\mathrm{Hz}$ and $\Gamma =1.7$. (a) At early stages $t=0.01\min$, all the particles located close to the vertical walls move downward, producing a fast motion of the intruder. Gray-scale sections, initially flat, curve themselves upward due to this motion. (b) $t=0.2\min$, the initial convection ceases at the lower regions of the cell (this occurs for low value of $\Gamma$). Thus, further deformations of the gray sections at these regions are no longer observed and convecting rolls develop progressively from the surface of the layer. (c) $t=9\min$, when the intruder center has reached the exponential tail of convection, it is lifted up by the ascent current. (d) $t=13\min$, fast rise of the intruder when trapped by the ascent convecting current. This configuration can be compared to Fig. 2(c) in Ref. 10.Reuse & Permissions

Figure 3

Upper panel: Schema of the nearest particles located around the intruder, labeled by the coordinate $\theta$. Lower panel: Time evolution of the angular positions of the particles located close to the intruder, with time resolution of $1\mathrm{ms}$, for the vertical intruder step observed in curve 1 of Fig. 1, around $t_1$. For $\Gamma =1.7$ and $f=15\mathrm{Hz}$. Notice that as time evolves (increasing toward the bottom of the figure), a collective motion of small particles occurs toward the intruder bottom.Reuse & Permissions

Figure 4

Time average over $6\mathrm{s}$ of the normal impulse acting on the intruder as a function of the angular position $\theta$, for constant frequency $f=15\mathrm{Hz}$ and $\Gamma =1.7$. (a) Average during a time interval that includes a single jump up exhibited by curve 1 on Fig. 1, around $t_1$. For the arching regime, a maximum of the impulse is observed at the left side of the intruder. At the right side, due to the mobility of small particles associated to the higher concentration of vacancies, the impulse is spread out. (b) Average over a time interval, which does not exhibit any jump up of the intruder, obtained in the flat part of curve 1 on Fig. 1, around $t_3$. (c) Average around $t_4$, in the convective regime.Reuse & Permissions

Figure 5

Effect of packing on segregation intensity $\Phi$. (a) Snapshots of hexagonal packing case. (b) The corresponding convection intensity $\Phi$. (c) and (d) Similar to (a) and (b) for the disordered packing. In both cases, $\Gamma =1.7$, $\eta =13$, and $f=15\mathrm{Hz}$.Reuse & Permissions

Figure 6

The vertical position of several size intruders as function of time, for a constant frequency $f=15\mathrm{Hz}$ and a constant acceleration $\Gamma =1.7$, for an initial hexagonal packing. Intruder to particle diameter ratio from left to right; $\eta =13$, $\eta =7$, and $\eta =3$. The left inset shows the rise times for the hexagonal packing (HP) and the disordered packing (DP), for $\eta =13$. Right inset compares the intruder speed in the convective regime for HP and DP packingReuse & Permissions