Author(s): Hamidreza Jamshidnia; Yasushi Takeda
Linked Author(s): Hamidreza Jamshidnia
Keywords: Standing Baffle; UVP; Spatial and temporal structure; Turbulence intensity; Power spectra; PCP
Abstract: The effect of an intermediate standing baffle on the structure of flow in a rectangular open channel has been successfully captured by technique of Ultrasonic Doppler Velocimetry (UVP). Various spatial distributions such as on-axis time-averaged velocity profiles and turbulent intensities at different streamwise positions indicates the flow structure of the uprising flow at the upstream of baffle, vortex shedding and flow separation, change of the effective cross-section at immediate downstream of the baffle and recirculation flow at the downstream of the baffle. These phenomena are also reflected in the peak values of the turbulent intensity profiles. Time-space onaxis velocity color-map of upstream and downstream sections confirms the existence of periodic change of flow direction near the edge of the baffle at downstream sections. The captured phenomena were also categorized by observing and categorizing four types of Phenomenological Zero Crossing Points (PCP).
Year: 2009