Print Email Facebook Twitter Large-Scale Structure of the Turbulent Wake Behind a Flat Plate Title Large-Scale Structure of the Turbulent Wake Behind a Flat Plate Author Jovic, S. Ramaprian, B.R. Corporate name TU Delft Date 1986-03-01 Abstract An experimental study of the developing two-dimensional turbulent wake behind a streamlined flat-plate is reported. The purpose of this study was to understand the evolution of the wake structure from the one characteristic of the boundary layer to that characteristic of the far-wake, and to investigate whether organized motions are present in the wake flow just as in other free shear flows. The evolution of the flow and the mixing process in the developing wake was studied by using the well-known heat-tagging technique. This consisted of heating very slightly the boundary layer on one side of the plate, so that heat could be used as a passive tracer. The experiments were performed in a wind tunnel at a Reynolds number (based on the trailing-edge momentum thickness) of 1100. Simultaneous measurements of two components of velocity and local temperature were made. The data were obtained at eight stations over the distance range of 0, starting at the trailing edge, to 260 wake-momentum thicknesses and hence practically up to the far-wake. In addition to obtaining the usual conventionally averaged turbulence properties, special procedures such as conditional averaging and selective ensemble averaging were employed to analyse the data. The conditional averaging technique has been used to gain better insight into the dynamics of the interface separating the mixed and unmixed fluid in the developing wake. Finally, a selective ensemble averaging technique was successfully used to identify and educe organized large-scale structures present in the wake flow. Two types of structures were identified on one side of the wake, one originating from the same side of the wake centerline and the other one from the opposite side. The frequency of their occurrence and their dimensions, as well as all the properties associated with their organized and random motions are determined. Subject experimentalturbulenceturbulent wakewakeflow measurements Classification EHJ00EHD00EHP00 To reference this document use: http://resolver.tudelft.nl/uuid:c7ae566d-416a-454f-82d4-d1f18c1e4fac Publisher Iowa Institute of Hydraulic Research Source The University of Iowa - IIHR Report no. 298 Part of collection Hydraulic Engineering Reports Document type report Rights (c) 1986 IIHR Files PDF Jovic_Ramaprian1986.pdf 28.86 MB Close viewer /islandora/object/uuid:c7ae566d-416a-454f-82d4-d1f18c1e4fac/datastream/OBJ/view