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Memorias de investigación
Artículos en revistas:
Direct and adjoint global stability analysis of turbulent transonic flows over a NACA0012 profile
Año:2014
Áreas de investigación
  • Física química y matemáticas,
  • Dinamica de fluidos,
  • Ingenierías
Datos
Descripción
In this work, various turbulent solutions of the two-dimensional (2D) and three-dimensional compressible Reynolds averaged Navier?Stokes equations are analyzed using global stability theory. This analysis is motivated by the onset of flow unsteadiness (Hopf bifurcation) for transonic buffet conditions where moderately high Reynolds numbers and compressible effects must be considered. The buffet phenomenon involves a complex interaction between the separated flow and a shock wave. The efficient numerical methodology presented in this paper predicts the critical parameters, namely, the angle of attack and Mach and Reynolds numbers beyond which the onset of flow unsteadiness appears. The geometry, a NACA0012 profile, and flow parameters selected reproduce situations of practical interest for aeronautical applications. The numerical computation is performed in three steps. First, a steady baseflow solution is obtained; second, the Jacobian matrix for the RANS equations based on a finite volume discretization is computed; and finally, the generalized eigenvalue problem is derived when the baseflow is linearly perturbed. The methodology is validated predicting the 2D Hopf bifurcation for a circular cylinder under laminar flow condition. This benchmark shows good agreement with the previous published computations and experimental data. In the transonic buffet case, the baseflow is computed using the Spalart?Allmaras turbulence model and represents a mean flow where the high frequency content and length scales of the order of the shear-layer thickness have been averaged. The lower frequency content is assumed to be decoupled from the high frequencies, thus allowing a stability analysis to be performed on the low frequency range. In addition, results of the corresponding adjoint problem and the sensitivity map are provided for the first time for the buffet problem. Finally, an extruded three-dimensional geometry of the NACA0012 airfoil, where all velocity components are considered, was also analyzed as a Triglobal stability case, and the outcoming results were compared to the previous 2D limited model, confirming that the buffet onset is well detected.
Internacional
Si
JCR del ISI
Si
Título de la revista
International Journal for Numerical Methods in Fluids
ISSN
1097-0363
Factor de impacto JCR
1,329
Información de impacto
ISI Journal Citation Reports © Ranking: 2013: 19/31 (Physics Fluids & Plasmas); 32/95 (Mathematics Interdisciplinary Applications); 58/102 (Computer Science Interdisciplinary Applications); 63/139 (Mechanics)
Volumen
76
DOI
10.1002/fld.3929
Número de revista
3
Desde la página
147
Hasta la página
168
Mes
SEPTIEMBRE
Ranking
Esta actividad pertenece a memorias de investigación
Participantes
  • Autor: Esteban Ferrer Vaccarezza (UPM)
  • Autor: Leo Miguel Gonzalez Gutierrez (UPM)
Grupos de investigación, Departamentos, Centros e Institutos de I+D+i relacionados
  • Creador: Departamento: Mecánica de Fluidos y Propulsión Aeroespacial
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