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Bursts in turbulent shear flows
The Physics of Fluids, 1976The burst frequency or frequency of regions in a turbulent flow where the energy dissipation is large has been measured in both laboratory and atmospheric shear flows. The laboratory measurements were made in two slightly heated flows, a boundary layer in zero pressure gradient and an axisymmetric jet with a co-flowing external system.
R. A. Antonia, H. Q. Danh, A. Prabhu
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Management and Control of Turbulent Shear Flows
ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, 1993AbstractThis survey will begin with a few historical aspects, describe some passive and active management methods, and discuss selected examples of manipulation of leading edge separation. It will then deal with some typical flow phenomena which are important for the manipulation of turbulent shear flows.
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1997
We will consider here developed turbulence submitted to a shear, both from a very simple statistical point of view (mixing-length theory) and from the coherent-structure point of view. We will be interested in flows such as free-shear flows (mixing layers, jets and wakes) and wall flows.
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We will consider here developed turbulence submitted to a shear, both from a very simple statistical point of view (mixing-length theory) and from the coherent-structure point of view. We will be interested in flows such as free-shear flows (mixing layers, jets and wakes) and wall flows.
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Turbulent shear flows of variable density
6th Aerospace Sciences Meeting, 1968Abstract : A study was made of the mean flow field of free turbulent layers of variable density showing that if the velocity distribution in a particular constant-density flow is known, it is possible to obtain the corresponding variable-density velocity field without the introduction of a compressible turbulent viscosity.
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Model Equations for Turbulent Shear Flow
Studies in Applied Mathematics, 1974A set of model equations for the calculation of turbulent shear flows is presented. It is shown how the equations can be modified to allow for the inclusion of viscosity, compressibility and density variations. Some results of numerical computations are given.
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Journal of Fluid Mechanics, 1968
Townsend has derived a relation between mean vorticity and Reynolds stress valid in the wall layer of a turbulent flow. The vorticity Ω appears as a function of the local stress τ and its gradient. Such a relation is better suited for use in the vorticity equation than in the momentum equation.
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Townsend has derived a relation between mean vorticity and Reynolds stress valid in the wall layer of a turbulent flow. The vorticity Ω appears as a function of the local stress τ and its gradient. Such a relation is better suited for use in the vorticity equation than in the momentum equation.
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2000
Turbulent free shear flows occur if there are no walls directly at the flow. Figure 22.1 shows some examples: a free jet, a buoyant jet, a mixing layer with the free jet–boundary flow as a special case, and a wake flow. The corresponding laminar flows are treated in Sects. 7.2, 7.5, 10.5.4 and 12.1.5.
Hermann Schlichting, Klaus Gersten
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Turbulent free shear flows occur if there are no walls directly at the flow. Figure 22.1 shows some examples: a free jet, a buoyant jet, a mixing layer with the free jet–boundary flow as a special case, and a wake flow. The corresponding laminar flows are treated in Sects. 7.2, 7.5, 10.5.4 and 12.1.5.
Hermann Schlichting, Klaus Gersten
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Turbulence in shear flow with stability
Journal of Geophysical Research, 1959The turbulence energy balance is considered under conditions of mean-flow shear and varying density stratification, and it is concluded that: in a stable atmosphere the total turbulence energy is reduced; the maximum of the spectrum shifts to smaller scales; and, at heights large compared with the mixing length, the effects of the surface are ...
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On the Mechanism of Turbulent Shear Flows
Journal of Experimental and Theoretical Physics, 2019As a result of our analysis of some facts of turbulent flows, whose explanation is beyond the scope of existing semiempirical theories, in particular, our estimate of the effective roughness height in pipes with distributed roughness characterized by two or more length scales, we present a version of the theory of turbulent flows in channels with ...
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Bounds for turbulent shear flow
Journal of Fluid Mechanics, 1970Bounds on the transport of momentum in turbulent shear flow are derived by variational methods. In particular, variational problems for the turbulent regimes of plane Couette flow, channel flow, and pipe flow are considered. The Euler equations resemble the basic Navier–Stokes equations of motion in many respects and may serve as model equations for ...
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