boundary layer

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Related to Boundary-layer: Atmospheric 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 ?
Pop, Boundary-layer flow of nanofluids over a moving surface in a flowing fluid, Int.
The boundary-layer equations governing the flow and heat transfer of a non-Newtonian power-law fluids past a wedge are given by
So aircraft designers reduce drag, without compromising lift, by precisely placing a few small bumps or dips, called boundary-layer trips, on wings and blades.
Yazbak explains that information provided by flush-mounted thermocouples near equipment walls doesn't really represent the temperature of the rest of the melt steam due to boundary-layer flow effects and the fact that polymers are poor thermal conductors.
After presenting a range of basic concepts, he derives the incompressible Navier-Stokes equation and demonstrates the mathematical nature of their solutions, introduces the singular perturbation solutions then deals in turn with the inviscid outer solutions and the boundary-layer inner solutions, explains the separation of the boundary layer and its consequences and drag, presents both parallel and creeping-flow analytical solutions, and discusses turbulent flows.
Moreover, fluid mechanics and boundary-layer phenomena result in polymer flows with a number of distinct regions with regard to temperature, viscosity, and flow velocity.