Numerical and experimental investigation of a finite cylinder wake
Following a thorough time-resolved 2-D particle image velocimetry experimental investigation of the wake of a square wall-mounted finite cylinder, at Reynolds Re = 5.4 × 104 with aspect ratio H/d = 3, a 3-D DNS numerical investigation was performed under similar flow conditions and comparable Reynolds number (Re = 4.0 × 104). In this paper, the simulation results in four 2-D planes are compared to the experimental case using proper orthogonal decomposition (POD), spectral analysis and mean flow. Numerical and experimental POD modes were similar, with a few differences in mean flow values and main vortex emission frequency that can be explained by differences in boundary layer thickness. The investigated horizontal planes were z/H = 0.3, z/H = 0.5 and z/H = 1.0 planes, as well as the vertical x–z symmetry plane. While time-resolved experimental results were acquired independently for each investigated plane, numerical results were acquired concomitantly in all four planes, with full 3-D wake data available. The results in this paper confirm that the simulation is able to reproduce the main dynamic features of the flow, establishing the basis for deeper analysis of the full numerical data set in the future.
KeywordsCylinder wakes Finite cylinders Computational fluid dynamics Particle image velocimetry Low speed flow
List of symbols
Square cylinder side
Cylinder height coordinate
Total cylinder height
Reynolds number based on the cylinder side
99% Boundary layer thickness
The author thanks the Conselho Nacional de Pesquisa e Desenvolvimento (CNPq) for the support through the Grants: 402233/2013-1, 308829/2015-8—DT (Ana Cristina) and the process 381094/2016-2.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest regarding this research paper.
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