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http://dx.doi.org/10.3795/KSME-B.2011.35.7.709

Experimental Study on the Evolution of Tip Vortex Structures Generated by a Two-Bladed Rotor  

Sohn, Yong-Joon (School of Mechanical Engineering, Yeungnam Univ.)
Park, Byung-Ho (School of Mechanical Engineering, Yeungnam Univ.)
Han, Yong-Oun (School of Mechanical Engineering, Yeungnam Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.35, no.7, 2011 , pp. 709-715 More about this Journal
Abstract
In order to observe the wake interaction between tip vortices generated by a two-bladed rotor with slightly different pitch angles, the velocity components of the tip vortices were measured by using a two-dimensional LDV system. It was observed that the swirl velocity components of the ensuing blade deviated from the Vatistas' n = 2 vortex model and the axial velocity components of the preceding blade deviated from the Gaussian profile. It was also found that in the wake-age range of $200^{\circ}$ to $240^{\circ}$, the filament of the ensuing blade tip vortex was stretched as result of the closing in of two vortices. The results from these observations suggest the possibility that a similar wake interaction is generated in actual rotor blades, especially, in the ones with articulated hubs.
Keywords
Rotor Blade; Wake Age; Tip Vortex; Vortex Filament; LDV; Vortex Stretching;
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