Latest papers in fluid mechanics
Derivation of a realistic forcing term to reproduce the turbulent characteristics of round jets on the centerline
Author(s): Kyupaeck Jeff Rah, Chandru Dhandapani, and Guillaume Blanquart
Turbulence forcing techniques are often required in the numerical simulation of turbulent flows. A novel forcing technique, based on physics, is devised to reproduce the centerline turbulent characteristics of round jets in a triply periodic box.
[Phys. Rev. Fluids 3, 084606] Published Wed Aug 29, 2018
Author(s): JiaCheng Hu and Sean D. Peterson
An investigation of the interaction of a vortex ring colliding with a coaxially aligned aperture, which extends the classical problem of a vortex ring impacting a solid wall, examines the behaviors of near-wall vortices in the proximity of a structural discontinuity (aperture tip).
[Phys. Rev. Fluids 3, 084701] Published Wed Aug 29, 2018
Author(s): Dan Soto, Henri-Louis Girard, Antoine Le Helloco, Thomas Binder, David Quéré, and Kripa K. Varanasi
Factors governing atomization of droplets impacting a mesh, starting with the elementary unit of a single hole, are investigated. It is shown how this process can be used to generate finely controlled sprays with micrometric droplet sizes and low kinetic energy, as is critical for agricultural applications.
[Phys. Rev. Fluids 3, 083602] Published Tue Aug 28, 2018
Author(s): Hannu Teisala, Clarissa Schönecker, Anke Kaltbeitzel, Werner Steffen, Hans-Jürgen Butt, and Doris Vollmer
Wetting over liquid films governs important phenomena but is poorly understood. A water front moving over a micrometer-thick film of silicone oil on a solid surface is imaged. Capillary suction in the meniscus induces thinning of the oil film and a wavelike film profile with local backflows.
[Phys. Rev. Fluids 3, 084002] Published Tue Aug 28, 2018
Author(s): Takeru Morita, Toshihiro Omori, and Takuji Ishikawa
The artificial microswimmer is a cutting-edge technology with applications in drug delivery and micro-total-analysis systems. The flow field around a microswimmer can be regarded as Stokes flow, in which reciprocal body deformation cannot induce migration. In this study, we propose a microcapsule sw...
[Phys. Rev. E 98, 023108] Published Mon Aug 27, 2018
Author(s): Christophe Henry, Giorgio Krstulovic, and Jérémie Bec
This paper investigates the effect of inertia on the dynamics of elongated chains to go beyond the overdamped case that is often used to study such systems. For that purpose, numerical simulations are performed considering the motion of freely jointed bead-rod chains in an extensional flow in the pr...
[Phys. Rev. E 98, 023107] Published Fri Aug 24, 2018
Author(s): H. M. De La Rosa Zambrano, G. Verhille, and P. Le Gal
Aggregation and fragmentation are frequently observed in industrial and natural systems. In an experimental study, an initially large aggregate of magnetic particles is broken by the turbulent fluctuations of a flow. The size of the resulting clusters is measured using three-dimensional reconstruction.
[Phys. Rev. Fluids 3, 084605] Published Fri Aug 24, 2018
Slippage effect on the dispersion coefficient of a passive solute in a pulsatile electro-osmotic flow in a microcapillary
Author(s): J. Muñoz, J. Arcos, O. Bautista, and F. Méndez
The dispersion coefficient of a passive solute into a pulsatile electroosmotic flow with slippage at the microcapillary wall is derived. We found that the slip condition can enhance the dispersion coefficient by up to two orders of magnitude over the no-slip condition.
[Phys. Rev. Fluids 3, 084503] Published Thu Aug 23, 2018
Author(s): Hidenori Tanaka, Alpha A. Lee, and Michael P. Brenner
[Phys. Rev. Fluids 3, 089901] Published Thu Aug 23, 2018
Author(s): Pedro S. Volpiani, Matteo Bernardini, and Johan Larsson
The effects of wall thermal conditions on the canonical case of an impinging shock wave interacting with a turbulent boundary layer is an under-explored topic. Direct numerical simulations are used to study the flow properties of supersonic shock/boundary-layer interactions with distinct wall thermal conditions and shock angles.
[Phys. Rev. Fluids 3, 083401] Published Wed Aug 22, 2018
Author(s): Evan H. Anders, Benjamin P. Brown, and Jeffrey S. Oishi
A mechanism for rapidly achieving thermal relaxation in high-Pe convective simulations is studied in the context of Rayleigh-Bénard convection. It achieves statistically similar states to standard timestepping and saves up to an order of magnitude in computational time for the problems studied.
[Phys. Rev. Fluids 3, 083502] Published Tue Aug 21, 2018
Author(s): Seong Jin Kim, Seungho Kim, and Sunghwan Jung
When a dog accelerates its tongue to lap water, a water column is created and pinches off close to the tongue. Physical experiments and a theoretical model of accelerating a solid sphere from a liquid bath elucidate the mechanism of the liquid-column formation and pinch-off.
[Phys. Rev. Fluids 3, 084001] Published Tue Aug 21, 2018
Author(s): S. Başbuğ, G. Papadakis, and J. C. Vassilicos
Fractal impellers can lead to a considerably shorter mixing time compared to regular impellers. This is explained by the differences in characteristics of flow and scalar fields. Moreover, a mathematical model is proposed which can approximate the decay rate of the passive scalar fluctuations.
[Phys. Rev. Fluids 3, 084502] Published Tue Aug 21, 2018
Author(s): Nisat Nowroz Anika, Lyazid Djenidi, and Sedat Tardu
Implementation of a bypass laminar-to-turbulent transition is explored. We show that our method, by bypassing linear exponential growth, can induce high mixing capacity localized turbulence in a laminar channel flow at low Re. An on-demand mixing enhancement in laminar channel flow is proposed.
[Phys. Rev. Fluids 3, 084604] Published Tue Aug 21, 2018
Author(s): Rodica Borcia, Michael Bestehorn, Sebastian Uhlig, Matthieu Gaudet, and Harald Schenk
An original mathematical tool suitable for describing fluid dynamics in micropumps induced by transverse forced vibrations of an elastic beam is presented. The model could also be used in designing engineering software for micromachinery applications.
[Phys. Rev. Fluids 3, 084202] Published Mon Aug 20, 2018
Reciprocal theorem for the prediction of the normal force induced on a particle translating parallel to an elastic membrane
Author(s): Abdallah Daddi-Moussa-Ider, Bhargav Rallabandi, Stephan Gekle, and Howard A. Stone
A solid sphere translating tangent to an elastic membrane is subject to a lift force perpendicular to its direction of motion. This effect is attributed to an elastohydrodynamic coupling that arises from the breaking of flow reversal symmetry induced by elastic deformation.
[Phys. Rev. Fluids 3, 084101] Published Fri Aug 17, 2018
Author(s): Emre Turkoz, SeungYeon Kang, Luc Deike, and Craig B. Arnold
The process of blister-actuated laser-induced forward transfer (BA-LIFT) results in focused jets which are thinner and faster than regular jets.
[Phys. Rev. Fluids 3, 082201(R)] Published Wed Aug 15, 2018
Observation of a link between energy dissipation rate and oscillation frequency of the large-scale circulation in dry and moist Rayleigh-Bénard turbulence
Author(s): Dennis Niedermeier, Kelken Chang, Will Cantrell, Kamal Kant Chandrakar, David Ciochetto, and Raymond A. Shaw
An investigation of both the large- and small-scale flow properties of moist and cloudy, turbulent Rayleigh-Bénard convection suggests that the large scale circulation is insensitive to phase composition/interfacial physics; rather, it depends only on the strength of the turbulence.
[Phys. Rev. Fluids 3, 083501] Published Wed Aug 15, 2018
Dynamics of paramagnetic and ferromagnetic ellipsoidal particles in shear flow under a uniform magnetic field
Author(s): Christopher A. Sobecki, Jie Zhang, Yanzhi Zhang, and Cheng Wang
We theoretically and numerically study the effects of a uniform magnetic field on the dynamics of ellipsoidal ferromagnetic and paramagnetic particles in a simple shear flow at low Reynolds number. With numerical simulations we further illustrate their lateral migration in wall-bounded shear flows.
[Phys. Rev. Fluids 3, 084201] Published Tue Aug 14, 2018
Author(s): Rausan Jewel, Andreea Panaitescu, and Arshad Kudrolli
The drag experienced by a spherical intruder settling through a medium composed of transparent granular hydrogels and water is measured as a function of its speed and depth. Internal visualization of the medium shows its flow to be localized around the advancing intruder.
[Phys. Rev. Fluids 3, 084303] Published Tue Aug 14, 2018