Two-component particle image velocimetry was employed to measure the influence of surface roughness on a Mach 2 boundary layer. Three surface conditions were examined: a smooth wall, patterned diamond-shaped roughness, and an approximately random realistic roughness. The response of the boundary layer was characterized in ensemble-averaged measurements of the mean velocity and Reynolds stresses. The streamwise development of the mechanical distortions introduced by the diamond-shaped roughness was also explored through observation of roughness-generated shock waves and changes in the boundary-layer profile. Measurements acquired at three streamwise locations are consistent with the trends observed in other studies when scaled by the roughness friction velocity. Ensemble-averaged outer-scaled streamwise velocity profiles showed a velocity deficit in the near-wall region. Inner-scaled boundary-layer profiles showed a downward vertical shift in the scaled velocities of 4.5 and 3 for the diamond roughness and nonuniform/realistic roughness topologies, respectively. These values show similar responses to the results seen in the literature for similar test conditions. The roughness effects were shown to increase in magnitude along the streamwise distance.
Characterizing Streamwise Development of Surface Roughness Effects on a Supersonic Boundary Layer
AIAA Journal ; 60 , 9 ; 5136-5149
01.09.2022
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
British Library Conference Proceedings | 2018
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