Accession Number : ADA270242


Title :   Relation between the Fluctuating Wall Pressure and the Turbulent Structure of a Boundary Layer on a Cylinder in Axial Flow


Descriptive Note : Doctoral thesis


Corporate Author : NORTHWESTERN UNIV EVANSTON IL


Personal Author(s) : Snarski, Stephen R


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a270242.pdf


Report Date : 12 Aug 1993


Pagination or Media Count : 260


Abstract : The turbulent flow structures responsible for the fluctuating wall pressure in the turbulent boundary layer on a cylinder in axial flow (delta/a = 5.04, Re sub Theta = 2870) have been investigated. Simultaneous measurements of the fluctuating wall pressure and turbulent streamwise velocities have been performed throughout a large volume of the boundary layer (y(+) = 14 to y/delta = 1.91, 0 or = x/delta or = 1.52, azimuthal angle phi = O deg, 20 deg, 40 deg) with a subminiature electret microphone (d(+) = 25.9) and hotwire velocity probe (1(+) = 18.5). Pressure-velocity cross-spectra and cross-correlation measurements indicate that two primary groups of pressure fluctuations exist in the cylindrical boundary layer: (1) small-scale, high-frequency disturbances concentrated close to the wall associated with the burst-sweep cycle and (2) large-scale, low-frequency disturbances extending from the wall to the turbulent/potential-flow interface that are consistent with a large Turbulence structure, Turbulent boundary layer, Cylindrical boundary layer, Transverse curvature, Wall pressure fluctuation


Descriptors :   *TURBULENT BOUNDARY LAYER , *CYLINDRICAL BODIES , *WALLS , *AXIAL FLOW , VELOCITY , MEASUREMENT , PROBES , VOLUME , HIGH FREQUENCY , PRESSURE GAGES , BOUNDARY LAYER FLOW , POTENTIAL FLOW , STREAMFLOW ANALYSIS , CROSS CORRELATION , REYNOLDS NUMBER , WIND TUNNELS , LOW FREQUENCY , MICROPHONES , SPECTRAL ENERGY DISTRIBUTION , ELECTRETS , TRANSVERSE , PRESSURE , CURVATURE , PRESSURE TRANSDUCERS , INTERFACES , BOUNDARY LAYER , TURBULENCE , TURBULENT FLOW


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE