In:
Physics of Fluids, AIP Publishing, Vol. 32, No. 11 ( 2020-11-01)
Abstract:
In this paper, we employ the high-fidelity spectral/hp method to investigate the control of wake turbulence behind a circular cylinder by direct numerical simulations. The preliminary results at Re = 500 show that, for rod rotation rate α & gt; 3, the cylinder wake is stabilized and the flow achieves a steady state. To further explore the efficiency of this control at the early turbulent regime, we further increase the Reynolds number to 3900. Compared to the bare cylinder, the drag coefficient is measured to reduce by 25.1% for α = 2. This drag reduction is expected to result from the pressure recovery effects of rotating rods. The statistical analysis, in terms of contours of Reynolds stresses and turbulence kinetic energy, and the turbulent wake visualization are then performed in order to show the alteration of turbulent flow. Furthermore, by applying Bernoulli equation to a streamline encircling the control rod, we show that the mechanism of pressure recovery is still viscous in the turbulent regime of Re = 3900. However, it is expected that the inertial effect sets out to play a significant role farther away from the main cylinder.
Type of Medium:
Online Resource
ISSN:
1070-6631
,
1089-7666
Language:
English
Publisher:
AIP Publishing
Publication Date:
2020
detail.hit.zdb_id:
1472743-2
detail.hit.zdb_id:
241528-8
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