Axisymmetric turbulent wakes with new nonequilibrium similarity scalings.
نویسندگان
چکیده
The recently discovered nonequilibrium turbulence dissipation law implies the existence of axisymmetric turbulent wake regions where the mean flow velocity deficit decays as the inverse of the distance from the wake-generating body and the wake width grows as the square root of that distance. This behavior is different from any documented boundary-free turbulent shear flow to date. Its existence is confirmed in wind tunnel experiments of wakes generated by plates with irregular edges placed normal to an incoming free stream. The wake characteristics of irregular bodies such as buildings, bridges, mountains, trees, coral reefs, and wind turbines are critical in many areas of environmental engineering and fluid mechanics.
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ورودعنوان ژورنال:
- Physical review letters
دوره 111 14 شماره
صفحات -
تاریخ انتشار 2013