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A vortex generator (VG) is one of the most successful devices used for suppression of flow separation. A conventional VG is a passive control device, so that it may suffer from an inherent drag penalty. As an alternative, we use a dielectric-barrier-discharge plasma actuator (PA) as a VG. Since few studies have been made on such a vortex generator-type plasma actuator (VG-PA), many questions still remain open, e.g., the effectiveness and the performance of the VG-PA for suppression of vortex shedding from a bluff body. In the present study, we experimentally evaluate the performance of the VG-PA by applying it to a pantograph head model of high-speed trains. The Reynolds number based on the freestream velocity and the width of the pantograph head model is 7200. The spanwise velocity induced by the VG-PA is about 33% of the freestream velocity. The flow field is measured by using particle image velocimetry. The present results show that the vortex shedding from a pantograph head model can significantly be suppressed by the VG-PA, which amounts to about 60% reduction in the transverse velocity fluctuations. It is also shown that a burst discharge control significantly improves the control effect in the single-side configuration, in which the vortex shedding is not much suppressed in the continuous mode.

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Vortex generator ( VG ) is one of the Inost successful fiow control devices ． A conventional VG is a passive control device ； lt does not adapt various velocity conditions ， As an alternative to the conventional VG ｝ we propose to use a plas1 皿 a actuator ( PA ) as a VG ． Since β ew studies have been made on such a vortex generator ． type plasma actuator ( VG − PA ) ， many questions still remain open ， e ． g ． ， the mechanism of vortex generation and the magnitude of generated vortex ． In the present study ， we experimentally characterize and evaluate a VG −PA and examine the effec 七 〇 f burst mode ． We also apply this VG − PA for suppression of vortex shedding 丘 om a panhead of used lbr high − speed trains． The present experiment shows that a VG − PA generates a distinct vortex 皿 d 七hat How separation around a panhead can be delayed by using VG − PA ， It is a ユ so shown that a VG −PA operated in the burst mode works differently as compared to that in七 he continuous mode ． Key Words： Active flow control ， Plasma actuater ， Vortex generator， Burst mode effect

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