Instantaneous velocity profile measurements in a turbulent boundary layer

摘要: Abstract Instantaneous wall shear stress and streamwise velocities have been measured simultaneously in a flat-plate, turbulent boundary layer at moderate Reynolds number an effort to provide experimental support for large eddy simulations. Data were obtained using buried-wire, gage hot-wire rake positioned the log region of flow. Fluctuations instantaneous U + versus Y profiles about mean law are shown be significant complex. Peak cross-correlation values between high, reflect passage structure inclined small angle wall. Estimates this consistent with those made by other investigators. Conditional sampling techniques used detect various sizes types flow disturbances (events), estimate their frequency occurrence. Events characterized sudden accelerations found highly coherent throughou...