This study intends to semi-analytically investigate the steady 3D boundary layer flow of a SiC-TiO2/DO hybrid nanofluid over a porous spinning disk subject to a constant vertical magnetic field. Here, the novel attitude to single-phase hybrid nanofluid model corresponds to considering nanoparticles and base fluid masses to compute solid equivalent volume fraction, solid equivalent de...

Two different approaches have been used to calculate turbulent flow along a long thin cylinder where the flow is aligned with the cylinder. A boundary-layer code is used to predict the mean flow for very long cylinders (length to radius ratio of up to O(10)), with the effects of the turbulence estimated through a turbulence model. Detailed comparison with experimental results shows that the mea...

The flow in an enclosed rotating cylinder with a stationary lower end wall is investigated numerically. For fast rotation rates, the flow in the interior is primarily in the azimuthal direction, with an angular momentum distribution very close to that corresponding to solid-body rotation for about the inner-half radius. The differential rotation sets up a large-scale circulation that is primari...

We study a boundary layer problem for the Navier-Stokes-alpha model obtaining a generalization of the Prandtl equations conjectured to represent the averaged flow in a turbulent boundary layer. We solve the equations for the semi-infinite plate, both theoretically and numerically. The latter solutions agree with some experimental data in the turbulent boundary layer.

As the number of applications of micro electro mechanical systems, or MEMS, increase, the variety of flow geometries that must be analyzed at the micro-scale is also increasing. To date, most of the work on MEMS scale fluid mechanics has focused on internal flow geometries, such as microchannels. As applications such as micro-scale flyers are considered, it is becoming necessary to consider ext...

The dynamical factors controlling the mean state and variability of the east Pacific intertropical convergence zone (ITCZ) and the associated cross-equatorial boundary layer flow are investigated using observations from the East Pacific Investigation of Climate (EPIC2001) project. The tropical east Pacific exhibits a southerly boundary layer flow that terminates in the ITCZ. This flow is induce...

In previous chapters boundary layers were evident as thin layers across which thermal, dynamic, and material properties of a free interior flow make a transition to their boundary values and/or boundary fluxes. In those cases the thinness of the boundary layer was typically a statement of the smallness of the relevant diffusivity; e.g., the depth h of the laminar Ekman boundary layer scales as ...

When a laminar boundary layer separates because of an adverse streamwise pressure gradient, the flow is subject to increased instability with respect to smallamplitude disturbances. Laminar–turbulent transition occurs under a rapid three-dimensional (3D) development within the separated shear layer. When the following turbulent boundary layer reattaches, a laminar separation bubble is formed. T...

Transition from laminar flow to turbulent flow occurs very often and plays a crucial role in many practical engineering flows. There are many different kinds of transition and broadly speaking they can be classified into three categories: classical transition in attached boundary; bypass transition in attached boundary layer and separated boundary layer transition. This paper presents a compara...

The interaction between a turbulent free-stream and a turbulent boundary layer is investigated through particle image velocimetry measurements. An ‘interaction layer’ located between 0.12 ≤ y/δ ≤ 0.19, at the end of the log layer, is identified whereby the kinetic energy in this layer describes the flow above it. Conditional averages about the interaction layer indicate that it is home to peaks...