Comparison of aerodynamic noise reduction effect and flow control mechanism by location of synthetic jet vent

Abstract

Reduction in aerodynamic noise emitted from a pantograph, especially pantograph head, is an important subject for environmental preservation and speed-up of Shinkansen trains. In the present study, synthetic jet actuators are applied to a pantograph head model with two types of vent locations, the one is the bottom ejection case, and the other is the front ejection case. Wind tunnel test and CFD analysis are carried out to investigate how the location of synthetic jet vent affects aerodynamic noise reduction effect and flow control mechanism. As a result, it is confirmed that the front ejection case can reduce aerodynamic peak noise more effectively than the bottom ejection case. Furthermore, the difference of flow control mechanism among these two vent location cases is clarified.