Non-equilibrium scaling laws in axisymmetric turbulent wakes
نویسندگان
چکیده
We present a combined Direct Numerical Simulation and Hot Wire Anemometry study of an axisymmetric turbulent wake. The data lead to a revised theory of axisymmetric turbulent wakes which relies on the mean streamwise momentum and turbulent kinetic energy equations, self-similarity of the mean flow, turbulent kinetic energy, Reynolds shear stress and turbulent dissipation profiles, non-equilibrium dissipation scalings and an assumption of constant anisotropy. This theory is supported by the present data up to a distance of 100 times the wake generator’s size which is as far as these data extend.
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