Interaction between two unequal particles at intermediate Reynolds numbers: A pattern of horizontal oscillatory motion

Deming Nie, Geng Guan, and Jianzhong Lin
Phys. Rev. E 103, 013105 – Published 14 January 2021

Abstract

The two-dimensional lattice Boltzmann method (LBM) was used to study the motion of two interacting particles with different densities (ρ1 and ρ2) and diameters (d1 and d2), which were placed in a vertical channel under gravity. Both the density ratio (λ=ρ2/ρ1) and diameter ratio (r=d2/d1) between the particles were considered. The transition boundaries between the regime where the particles settle separately and the regime where the particles interact are identified by λmax(r) and λmin(r); they exhibit excellent power-law relationships with r. A pattern of horizontal oscillatory motion (HOM), characterized by a structure with a large (but light) particle right above a small (but heavy) one and strong oscillations of both particles in the horizontal direction, was revealed for r0.3 at intermediate Reynolds numbers. The results indicate that the magnitude of oscillations decreases with λ, whereas the frequency displays the opposite trend. A sudden increase in the terminal velocity of particles is seen, illustrating a transition from the classical pattern of drafting, kissing, and tumbling to the HOM at a certain λ. Upon increasing λ, the pattern of HOM may bifurcate into a vertical steady state at low Re or small r. Furthermore, the effects of the confinement ratio and particle-to-fluid density ratio were also examined. The existence of a critical confinement ratio is observed, beyond which the particles interact in a different manner.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
14 More
  • Received 20 June 2020
  • Revised 22 December 2020
  • Accepted 23 December 2020

DOI:https://doi.org/10.1103/PhysRevE.103.013105

©2021 American Physical Society

Physics Subject Headings (PhySH)

Fluid Dynamics

Authors & Affiliations

Deming Nie1, Geng Guan1, and Jianzhong Lin2,*

  • 1Institute of Fluid Mechanics, China Jiliang University, Hangzhou, China
  • 2State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, China

  • *mecjzlin@public.zju.edu.cn

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 103, Iss. 1 — January 2021

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review E

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×