Mass-weighted turbulence measurements in a Mach 2.9 boundary layer with mild adverse and favorable pressure gradient
Conference Paper
Overview
Overview
abstract
1996, American Institute of Aeronautics and Astronautics, Inc. Mass-weighted-time, or Favre averaged, turbulence measurements were acquired in a Mach 2.9 air boundary layer (Re/m = 15 x106) subjected to both a mild adverse and favorable pressure gradient Crossfilm anemometry and conventional mean flow probe surveys were conducted across the boundary layers associated with flow over a curved compression ( 1.7) and expansion ( -1.2) wall. Detailed upstream measurements allowed for a comparison with a zero pressure gradient boundary layer. Measured turbulence data include the mean Favre velocity fluctuations, u, v, and w, the x-y and x-z plane turbulent shear stresses pu v and pu w. Velocity profiles were also acquired. The x-y turbulent shear stress distributions and magnitudes were found to be strongly affected by the pressure gradients. The peak turbulent shear stresses for the adverse pressure gradient case were found to amplified by a nominal 270%; the favorable pressure gradient peak values were amplified by 120%. The x-z shear stresses were not as strongly affected by the pressure gradients. Of the three mean Favre velocity fluctuation components, v was influenced the most by the pressure gradients.
