منابع مشابه
A linear process in wall-bounded turbulent shear flows
A linear process in wall-bounded turbulent shear flows has been investigated through numerical experiments. It is shown that the linear coupling term, which enhances non-normality of the linearized Navier–Stokes system, plays an important role in fully turbulent—and hence, nonlinear —flows. Near-wall turbulence is shown to decay without the linear coupling term. It is also shown that near-wall ...
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The dynamical theory of moderate Reynolds number turbulence triangulates the infinite-dimensional Navier-Stokes state space by sets of exact solutions (equilibria, relative equilibria, periodic orbits, ...) which form a rigid backbone which enables us to describe and predict the sinuous motions of a turbulent fluid. We report determination of a set of unstable periodic orbits from close recurre...
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Expressions for variation of skin friction with Reynolds number in fully developed turbulent channel/pipe flows and in zero pressure gradient boundary layers are derived. The proposed in this paper asymptotic (Reδ = δ(x)U ν → ∞) theory is formulated as a convergent perturbation expansion in powers of small dimensionless parameters dδ dx → 0 and u∗ U → 0 applied directly to the Navier-Stokes equ...
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ژورنال
عنوان ژورنال: Annual Review of Fluid Mechanics
سال: 2020
ISSN: 0066-4189,1545-4479
DOI: 10.1146/annurev-fluid-010719-060221