S054044 Acoustic Control of Rectangular Jet : Influence of Excitation Pattern on Vortex behavior
S054044 音波による長方形噴流の制御 : 渦構造に及ぼす励起パターンの影響([S05404]噴流,後流,およびはく離流れの基礎と応用:最前線(4))

Megumi TSUTSUI, Shouichiro IIO, Yoshiaki HANEDA, Toshihiko IKEDA
2011 The Proceedings of Mechanical Engineering Congress Japan  
Active control ofa rectangular jet has been attempted to rnanipulate the vortex shedding interval in the major shear IayeL The aspect ratio ofthe nozzle cross − section is 15, and the Reynolds number based on the shorter side length ofthe nozzle is 6700 . It is considered essential that the vortex distribution along the each major shear layer plays an important role to characterize a rectangular jet behavioL In the present investigation , it was remarkably observed that the jet spreads more
more » ... ly in the minor directlon and contracts more greatly in major direction by the asymmetric excitation than that of the non −excited jet . Hot wire measurement was conducted , and could provide the mean , coherent and random velocity components from the instantaneous velocity signal . The measurement results showed that t わe coherent vortices are generated in synchronization with the excitation frequency and the rnode . In addition , it was revealed that the inclined vortex rings are formed and interacted with each other only when the jet was excited by asymmetric mode . Thejet spreading is attributed to the tilting alignment ofthe vortex ring , and thejet contracting in minor direction is due to the selfLinduced defbrmation ofthe rectangular vortex ring .
doi:10.1299/jsmemecj.2011._s054044-1 fatcat:2ihohy7rynbpxlsos4ad5tjmze