Boundary-layer receptivity under interaction of free-stream turbulence and localized wall roughness

• Published in: Applied mathematics and mechanics Vol. 37; no. 3; pp. 349 - 360
• Main Authors: Shen, Luyu, Lu, Changgen
• Format: Journal Article
• Language: English
• Published: Shanghai Shanghai University 01.03.2016; School of Atmospheric Science, Nanjing University of Information Science and Technology, Nanjing 210044, China%School of Marine Science, Nanjing University of Information Science and Technology, Nanjing 210044, China
• Subjects: Applications of Mathematics; Classical Mechanics; Fluid- and Aerodynamics; Mathematical Modeling and Industrial Mathematics; Mathematics; Mathematics and Statistics; Partial Differential Equations; localized wall roughness; O357; boundary-layer receptivity; Tollmien-Schlichting (T-S) wave; 76F65; 76D05; free-stream turbulence (FST)
• ISSN: 0253-4827; 1573-2754
• DOI: 10.1007/s10483-016-2037-6

The boundary-layer receptivity under the interaction of free-stream turbu- lence （FST） and localized wall roughness is studied by the direct numerical simulation （DNS） and the fast Fourier transform. The results show that the Tollmien-Schlichting （T-S） wave packets superposed by a group of stability, neutral, and instability T-S waves are generated in the boundary layer. The propagation speeds of the T-S wave packets are calculated. The relation among the boundary-layer receptivity response, the amplitude of the FST, the roughness height, and the roughness width is determined. The results agree well with Dietz＇s experiments. The effect of the roughness geometries on the receptivity is also studied.