6533b829fe1ef96bd128ae87
RESEARCH PRODUCT
Effects of roughness on particle dynamics in turbulent channel flows: a DNS analysis
Gaetano SardinaEnrico NapoliMauro De MarchisBarbara Milicisubject
PhysicsParticle statisticsTurbulenceMechanical Engineeringmedia_common.quotation_subjectParticle-laden flowsProbability density functionMechanicsCondensed Matter PhysicsTracking (particle physics)Inertiamultiphase and particle-laden flows particle/fluid flows turbulent flowsPhysics::Fluid DynamicsMechanics of MaterialsParticleParticle velocitymedia_commondescription
AbstractDeposition 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 wall-bounded 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.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-01-02 | Journal of Fluid Mechanics |