boundary layer

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Related to Boundary layers: Turbulent Boundary Layer

boundary layer

In fluidics, a narrow region next to a fixed boundary or surface where the fluid velocity rapidly changes from zero to some finite value.

boundary layer

microscopic layer of fluid (liquid or gas) next to the surface of a body or object moving relative to it, important in considering the drag force upon the object. laminar boundary layer layer which is next to the surface of an object, not mixing with the flow further away from the surface, and so can be considered to be a discrete layer in a plane parallel to the main flow. turbulent boundary layer layer which is next to the surface of an object, but in this case mixing with the flow further away from it. An example of a boundary layer change is that due to a dimpled golf ball in flight: the dimples make the boundary layer turbulent, which reduces drag caused by the pressure being lower behind the ball, so less energy is lost to the flow.
References in periodicals archive ?
In the final effect of horizontal plates, two symmetrical boundary layers exist, growing from each edge (region I = region II) and transforming at the separation point into free stream heat convection (plume).
Rajagopalan, 1991: Rough-wall turbulent boundary layers.
To avoid the effects of the nozzle boundary layers on the aerodynamics of the car models, a ground plate with a length of 4.
Recently, Sajjad[16] considered MHD forced convective boundary layer flow of micropolar fluids past a shrinking porous sheet prescribed with variable heat flux and heat source.
The aim of this study is to investigate, the effect of physical parameters on boundary layer flow of nanofluids over a flat plate.
On the boundary layers oscillated with oscillating streams, Applied Scientific Research 10(1): 23-36.
A particularly interesting form of flame flashback occurs inside the velocity boundary layer close to solid walls.
The calibration and tuning of turbulence models necessitates forumulation of parameters and scales which can be validated by experimental data on pressure gradient boundary layers.
During the flowing of air between two flat plates, the temperature boundary layer is expanded from the leading edge separation point.
The study of thermal boundary layer problem for two-dimensional steady and incompressible laminar flow past a wedge has received considerable interest in the field of aerodynamics.
In addition, previous research on small crustaceans and insects demonstrated that flows through gaps between adjoining cylindrical elements in setal arrays can be diminished by the relatively thick boundary layers at low and intermediate Re flows (Cheer and Koehl, 1987a, b; Koehl, 1998) and that variations in flexible element spacing during motion can further decrease flow between adjacent appendage elements (Fernier and Gaylord, 2008).
Let us mention that an appropriate definition of [tau] at outflow Dirichlet boundaries is important also in real-life applications although sometimes it is claimed that outflow boundary layers are mainly encountered in academic problems.