On Subharmonic Resonance and Other Nonlinear Mechanisms in Wavepackets in Boundary Layers

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Author(s):	Martinez, A. G. ; Himeno, F. H. T. ; Mathias, M. S. ; Medeiros, M. A. F. ; Sherwin, S ; Schmid, P ; Wu, X Total Authors: 7
Document type:	Journal article
Source:	IUTAM LAMINAR-TURBULENT TRANSITION; v. 38, p. 9-pg., 2022-01-01.
Abstract
On airplanes, transition often initiates from small and irregular disturbances introduced into the boundary layer. These disturbances produce TS waves which are modulated both in streamwise and spanwise directions. Such waves are well represented by wavepackets, whose most salient nonlinear feature is the growth of oblique low frequency waves. Experimental results, presented in the literature, additionally indicate the nonlinear growth of fundamental modes. Interestingly, DNS results presented here and in the literature, indicate the nonlinear subharmonic modes are well reproduced numerically but this is not observed for the fundamental modes. Our results also show the subharmonic resonance is substantially less active than previously thought. (AU)

FAPESP's process:	18/04584-0 - Computational study of the effect of a small cavity on the transition of a compressible boundary layer
Grantee:	Marlon Sproesser Mathias
Support Opportunities:	Scholarships in Brazil - Doctorate


FAPESP's process:	18/02542-9 - Numerical study of wave packets over a flat plate with roughness
Grantee:	Fernando Henrique Tadashi Himeno
Support Opportunities:	Scholarships in Brazil - Doctorate