抄録
Measurements of fluctuating static-pressure in a rectangular jet were conducted to educe three-dimensional vortical structure with phase-averaging technique. The experiments were performed for the air issuing from a sharp-edged rectangular orifice. The jet was excited at the interaction mode, where the stable interaction of vortices was generated. For phase-averaging processing, the reference signals were detected by a single normal hot-wire probe fixed at a downstream station whose distance from the jet exit corresponded to an equivalent diameter of the exit, and fluctuating static-pressure were measured over the flow field by a static pressure probe. Phase-average incoherent fluctuating static-pressure, which is related to jittering motions of vortices and is defined in phase-averaging, and adequacy of Taylor hypothesis to obtain three-dimensional structure were discussed. The results suggested that interaction and stretching of vortices contributes to generation of the incoherent vortex motions, and the use of a constant convection velocity in the hypothesis is acceptable for qualitative consideration.
