Effects of roughness on particle dynamics in turbulent channel flows: a DNS analysis

Enrico Napoli, Barbara Milici, Mauro De Marchis, Gaetano Sardina

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Deposition and resuspension mechanisms in particle-laden turbulent flows are dominated by the coherent structures arising in the wall region. These turbulent structures, which control the turbulent regeneration cycles, are affected by the roughness of the wall. The particle-laden turbulent flow in a channel bounded by irregular two-dimensional rough surfaces is analysed. The behaviour of dilute dispersions of heavy particles is analysed using direct numerical simulations (DNS) to calculate the three-dimensional turbulent flow and Lagrangian tracking to describe the turbophoretic effect associated with two-phase turbulent flows in a complex wallbounded domain. Turbophoresis is investigated in a quantitative way as a function of the particle inertia. The analysis of the particle statistics, in term of mean particle concentration and probability density function (p.d.f.) of wall-normal particle velocity, shows that the wall roughness produces a completely different scenario compared to the classical smooth wall. The effect of the wall roughness on the particle mass flux is shown for six particle populations having different inertia.
Original languageEnglish
Pages (from-to)465-478
Number of pages14
JournalJournal of Fluid Mechanics
Volume739
Publication statusPublished - 2014

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Direct numerical simulation
channel flow
Channel flow
direct numerical simulation
Turbulent flow
roughness
Surface roughness
turbulent flow
inertia
Probability density function
Mass transfer
Statistics
particle mass
probability density functions
regeneration
statistics
cycles

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this

Effects of roughness on particle dynamics in turbulent channel flows: a DNS analysis. / Napoli, Enrico; Milici, Barbara; De Marchis, Mauro; Sardina, Gaetano.

In: Journal of Fluid Mechanics, Vol. 739, 2014, p. 465-478.

Research output: Contribution to journalArticle

Napoli, Enrico ; Milici, Barbara ; De Marchis, Mauro ; Sardina, Gaetano. / Effects of roughness on particle dynamics in turbulent channel flows: a DNS analysis. In: Journal of Fluid Mechanics. 2014 ; Vol. 739. pp. 465-478.
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