Computational study of the effect of a small cavity on the transition of a compressible boundary layer

• Grant number: 18/04584-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2018
• End date: December 31, 2021
• Field of knowledge: Engineering - Aerospace Engineering - Aerodynamics
• Principal Investigator: Marcello Augusto Faraco de Medeiros
• Grantee: Marlon Sproesser Mathias
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

This research proposal involves the effect of small cavities or other imperfections on a flat plate over the transition from the linear to the turbulent regime of a compressible flow. Accurately predicting this transition is of great importance for the drag reduction of and aerodynamic project, leading to a lower overall fuel consumption of aircrafts of other vehicles, especially at high speed conditions, such as a cruise. Estimating the transition location is still a challenge and the effect of imperfections is a parameter that must be better understood to make projects more efficient, for example, by better understanding the tolerances that must be specified for manufacturing.For this goal to be achieved, two computational tools will be used. The first is a code for the Direct Numerical Simulation (DNS) of the flow. The second is a global stability analysis routine, which uses the Linear Stability Theory (LST). Este DNS é capaz de simular o escoamento com grande precisão em uma ampla faixa de frequências, essencial para este tipo de estudo, pois ondas de pequena magnitude já são capazes de desencadear o processo de transição. O LST possibilita a obtenção de uma grande gama de modos de oscilação do escoamento. Modos secundários de instabilidade também serão levados em conta. This DNS can simulate the flow with great accuracy in a wide range of frequencies, which is essential for this type of study because of the small magnitude of waves able to trigger the transition process. The LST makes it possible to obtain a wide range of flow oscillation modes. Secondary instability modes will also be considered.Most previous work on the influence of imperfections on the transitions considers the disturbances to be generated by the imperfection itself; what is expected to be gained during the development of this project is to understand the interaction of existing waves with such imperfections, as it occurs in real situations. (AU)

Scientific publications

(7)

(The scientific publications listed on this page originate from the Web of Science or SciELO databases. Their authors have cited FAPESP grant or fellowship project numbers awarded to Principal Investigators or Fellowship Recipients, whether or not they are among the authors. This information is collected automatically and retrieved directly from those bibliometric databases.)

MATHIAS, MARLON SPROESSER; FARACO DE MEDEIROS, MARCELLO AUGUSTO. Optimal computational parameters for maximum accuracy and minimum cost of Arnoldi-based time-stepping methods for flow global stability analysis. THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS, v. 36, n. 6, p. 24-pg., 2022-11-06. (17/23622-8, 18/04584-0, 19/15366-7, 13/07375-0)

MATHIAS, MARLON S.; MEDEIROS, MARCELLO A. F.. Global instability analysis of a boundary layer flow over a small cavity. AIAA AVIATION 2019 FORUM, v. N/A, p. 13-pg., 2019-01-01. (17/23622-8, 18/04584-0)

MATHIAS, MARLON SPROESSER; MEDEIROS, MARCELLO A. F.. The effect of incoming boundary layer thickness and Mach number on linear and nonlinear Rossiter modes in open cavity flows. THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS, v. 35, n. 4, MAY 2021. (17/23622-8, 13/07375-0, 18/04584-0)

MARTINEZ, A. G.; HIMENO, F. H. T.; MATHIAS, M. S.; MEDEIROS, M. A. F.; SHERWIN, S; SCHMID, P; WU, X. On Subharmonic Resonance and Other Nonlinear Mechanisms in Wavepackets in Boundary Layers. IUTAM LAMINAR-TURBULENT TRANSITION, v. 38, p. 9-pg., 2022-01-01. (18/04584-0, 18/02542-9)

MATHIAS, MARLON SPROESSER; FARACO DE MEDEIROS, MARCELLO AUGUSTO. Interaction between Rossiter and Gortler modes in the compressible flow in an open cavity. AIAA AVIATION 2020 FORUM, v. N/A, p. 6-pg., 2020-01-01. (18/04584-0, 17/23622-8)

MATHIAS, MARLON S.; MEDEIROST, MARCELLO A. F.. Spatial instability of boundary layers over small cavities and comparison to global modes. AIAA AVIATION 2021 FORUM, v. N/A, p. 8-pg., 2021-01-01. (19/15366-7, 13/07375-0, 18/04584-0, 17/23622-8)

HIMENO, FERNANDO H. T.; MATHIAS, MARLON S.; FARACO DE MEDEIROS, MARCELLO AUGUSTO. DNS of a Tollmien-Schlichting Wave Interacting with a Roughness Modeled via Body-fitted and Approximation Methods. AIAA AVIATION 2021 FORUM, v. N/A, p. 10-pg., 2021-01-01. (18/02542-9, 13/07375-0, 18/04584-0)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MATHIAS, Marlon Sproesser. Computational study of the hydrodynamic stability of gaps and cavities in a subsonic compressible boundary layer. 2021. Doctoral Thesis - Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD) São Carlos.