Inducing spanwise motions in the vicinity of solid boundaries alters energy, mass and/or momentum transfer. Under some conditions, these are such that drag is reduced transition to turbulence delayed. There several possibilities induce those motions, be it through active imposition a predefined velocity distribution at walls or by careful design wall shape, which corresponds passive control.In ...

In the fields of engineering, especially in heat transfer area, contribution fluid flows through different channels is remarkable. Among available shapes channel, sinusoidal wavy are considered more efficient areas such as cooling electronic devices, boilers, biomedical applications, etc., due to their increased recirculation capability mixing flowing fluids - which increases performance, conse...

Chaotic transport and mixing in wavy cylindrical Couette flow has been studied in some detail, but previous studies have been limited to the velocity field at transition from Taylor–Couette flow to wavy flow or have used phenomenological, computational, or theoretical models of the flow. Recent particle image velocimetry measurements of wavy vortex flow provide the experimental three-dimensiona...

Direct numerical simulation of three-dimensional (3D) viscous flow in a wavy pipe is performed using the lattice Boltzmann approach, to study 3D flow features in a curved pipe with nonuniform curvature. We first validate the lattice Boltzmann approach by simulating a transient flow in a straight pipe. In a wavy pipe, it is shown that the pressure gradient necessary to drive the flow depends mor...

Various micropatterns have been fabricated and used to regulate cell adhesion, morphology and function. Micropatterns created by standard photolithography process are usually rectangular channels with sharp corners (microgrooves) which provide limited control over cells and are not favorable for cell-cell interaction and communication. This paper proposes a new micropattern with smooth wavy sur...

This article can be considered as an extension of the paper of Fukagata et al. Phys. Fluids 14, L73 2002 which derived an analytical expression for the constituent contributions to skin friction in a turbulent channel, pipe, and plane boundary layer flows. In this paper, we extend the theoretical analysis of Fukagata et al. formerly limited to canonical cases with two-dimensional mean flow to a...

A novel wavy-walled bioreactor designed to enhance mixing at controlled shear stress levels was used to culture chondrocytes in suspension. Chondrocyte aggregation in suspensions mixed at 30, 50, and 80 rpm was characterized in the wavy-walled bioreactor and compared with that in conventional smooth-walled and baffled-walled spinner flask bioreactors. Aggregation was characterized in terms of t...