**Commenced**in January 2007

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**Edition:**International

**Paper Count:**30184

##### Phase-Averaged Analysis of Three-Dimensional Vorticity in the Wake of Two Yawed Side-By-Side Circular Cylinders

**Authors:**
T. Zhou,
S. F. Mohd. Razali,
Y. Zhou,
H. Wang,
L. Cheng

**Abstract:**

Thewake flow behind two yawed side-by-sidecircular cylinders is investigated using athree-dimensional vorticity probe. Four yaw angles (α), namely, 0°, 15°, 30° and 45° and twocylinder spacing ratios T* of 1.7 and 3.0 were tested. For T* = 3.0, there exist two vortex streets and the cylinders behave as independent and isolated ones. The maximum contour value of the coherent streamwise vorticity ~* ωx is only about 10% of that of the spanwise vorticity ~* ωz . With the increase of α, ~* ωx increases whereas ~* ωz decreases. At α = 45°, ~* ωx is about 67% of ~* ωz .For T* = 1.7, only a single peak is detected in the energy spectrum. The spanwise vorticity contours have an organized pattern only at α = 0°. The maximum coherent vorticity contours of ~* ω x and ~* ωz for T* = 1.7 are about 30% and 7% of those for T* = 3.0.The independence principle (IP)in terms of Strouhal numbers is applicable in both wakes when α< 40°.

**Keywords:**
Circular cylinder wake,
vorticity,
vortex shedding.

**Digital Object Identifier (DOI):**
doi.org/10.5281/zenodo.1336198

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