English
Related papers

Related papers: Reduced particle settling speed in turbulence

200 papers

The transport of heavy particles in a medium that consists of fluid and solid phases such as stream gravel beds, cracked soils and wetlands is affected by processes such as attachment-detachment, gravity and drag, and by mixing processes…

Fluid Dynamics · Physics 2018-01-23 Tomer Duman , Ran Holtzman , Uri Shavit

We report results from the first systematic Lagrangian experimental investigation in the regime of very light (air bubbles in water) and large particles (D/{\eta} >> 1) in turbulence. Using a traversing camera setup and particle tracking,…

A Schur decomposition of the velocity gradient tensor (VGT) for homogeneous, isotropic turbulence (HIT) is undertaken and its physical consequences examined. This decomposition permits the normal parts of the tensor (represented by the…

Fluid Dynamics · Physics 2017-10-10 Christopher J. Keylock

We integrate for the first time the hydrodynamic Hall-Vinen-Bekarevich-Khalatnikov equations of motion of a $^{1}S_{0}$-paired neutron superfluid in a rotating spherical shell, using a pseudospectral collocation algorithm coupled with a…

Astrophysics · Physics 2009-11-13 C. Peralta , A. Melatos , M. Giacobello , A. Ooi

We study the statistical properties of turbulence driven by structure formation in a massive merging galaxy cluster at z=0. The development of turbulence is ensured as the largest eddy turnover time is much shorter than the Hubble time…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Francesco Miniati

We use interface-resolved simulations to study finite-size effects in turbulent channel flow of neutrally-buoyant spheres. Two cases with particle sizes differing by a factor of 2, at the same solid volume fraction of 20% and bulk Reynolds…

Fluid Dynamics · Physics 2021-02-23 Pedro Costa , Francesco Picano , Luca Brandt , Wim-Paul Breugem

In this article, we investigate the inertial settling of an arbitrarily oriented cylinder settling under gravity. We focus on two regimes: the very short-time and long-time dynamic. By using the generalized Kirchhoff equations to describe…

Fluid Dynamics · Physics 2023-03-29 Jean-Lou Pierson

Slow dynamics in a fluid are studied in one of the most basic systems possible: polydisperse hard spheres. Monodisperse hard spheres cannot be studied as the slow down in dynamics as the density is increased is preempted by crystallisation.…

Soft Condensed Matter · Physics 2009-10-31 Richard P. Sear

We perform direct numerical simulations of a bi-disperse suspension of heavy spherical particles in forced, homogeneous, and isotropic three-dimensional turbulence. We compute the joint distribution of relative particle distances and…

Fluid Dynamics · Physics 2018-12-21 Akshay Bhatnagar , K. Gustavsson , B. Mehlig , Dhrubaditya Mitra

The impact of turbulent fluctuations on the forces exerted by a fluid on a towed spherical particle is investigated by means of high-resolution direct numerical simulations. The measurements are carried out using a novel scheme to integrate…

Fluid Dynamics · Physics 2016-11-21 Holger Homann , Jérémie Bec , Rainer Grauer

Preferential concentration of inertial particles by turbulence is a well recognized phenomenon. This study investigates how this phenomenon impacts the mean heat transfer between the fluid phase and the particle phase. Using direct…

Fluid Dynamics · Physics 2018-08-01 Hadi Pouransari , Ali Mani

The work described is concerned with the way micron-size particles attached to a surface are resuspended when exposed to a turbulent flow. An improved version of the Rock'n'Roll model (Reeks and Hall, 2001) is developed where this model…

Fluid Dynamics · Physics 2013-01-15 F. Zhang , M. Reeks , M. Kissane

We perform fully coupled numerical simulations using immersed boundary methods of finite-size spheres and fibres suspended in a turbulent flow for a range of Taylor Reynolds numbers $12.8<Re_\lambda<442$ and solid mass fractions $0\leq…

Fluid Dynamics · Physics 2024-05-16 Ianto Cannon , Stefano Olivieri , Marco E. Rosti

We use an extended laser Doppler technique to track optically the velocity of individual particles in a high Reynolds number turbulent flow. The particle sizes are of the order of the Kolmogorov scale and the time resolution, 30…

Fluid Dynamics · Physics 2009-11-13 Romain Volk , Nicolas Mordant , Gautier Verhille , Jean-François Pinton

We investigate experimentally phenomenon of turbulent thermal diffusion of micron-size solid particles in an inhomogeneous convective turbulence forced by one vertically-oriented oscillating grid in an air flow. This effect causes formation…

Fluid Dynamics · Physics 2024-04-19 E. Elmakies , O. Shildkrot , N. Kleeorin , A. Levy , I. Rogachevskii

The way particles interact with turbulent structures, particularly in regions of high vorticity and strain rate, has been investigated in simulations of homogeneous turbulence and in simple flows which have a periodic or persistent…

Fluid Dynamics · Physics 2012-05-28 Michael W. Reeks

We study the responses of fluid-immersed soft hydrogel spheres that are sheared under controlled volume fractions. Slippery, deformable particles along with the density-matched interstitial fluid are sandwiched between two opposing rough…

Soft Condensed Matter · Physics 2020-07-22 J. -C. Tsai , M. -R. Chou , P. -C. Huang , H. -T. Fei

The Lagrangian probability-density-function model, proposed in Part I for dense particle-laden turbulent flows, is validated here against Eulerian-Lagrangian direct numerical simulation (EL) data for different homogeneous flows, namely…

Fluid Dynamics · Physics 2018-03-02 Alessio Innocenti , Rodney O Fox , Maria Vittoria Salvetti , Sergio Chibbaro

We study the effect of particle shape on the turbulence in suspensions of spheroidal particles at volume fraction $\phi = 10\%$ and show how the near-wall particle dynamics deeply changes with the particle aspect ratio and how this affects…

Fluid Dynamics · Physics 2018-09-07 M. Niazi Ardekani , L. Brandt

Stability of coarse particles against gravity is an important issue in dense suspensions (fresh concrete, foodstuff, etc.). On the one hand, it is known that they are stable at rest when the interstitial paste has a high enough yield…

Soft Condensed Matter · Physics 2012-06-11 Guillaume Ovarlez , François Bertrand , Philippe Coussot , Xavier Chateau