Global instability analysis of a compressible laminar separation bubble

• Grant number: 15/26759-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2016
• End date: March 31, 2018
• Field of knowledge: Engineering - Aerospace Engineering - Aerodynamics
• Principal Investigator: Elmer Mateus Gennaro
• Grantee: Bruna Dias Pires de Souza
• Host Institution: Universidade Estadual Paulista (UNESP). Campus Experimental São João da Boa Vista. São João da Boa Vista , SP, Brazil

Abstract

Laminar flow separation and the formation of closed separation bubbles is a problem of primary technological significance due to its strong relation with the aerodynamic properties of lifting surfaces operating at high angles-of-attack. The behavior of these laminar separation bubbles (LSB) is believed to be dominated by hydrodynamic instability processes. The present project builds upon the idea put forward by U. Dallmann in the late 80s, that a global instability mechanism may exist acting on two-dimensional recirculating flows, that under an infinitesimally weak perturbation originates a fully three-dimensional flow. In previous research Rodríguez, Gennaro e Juniper (2013) demonstrated that this instability is recovered as a 3D Eigen mode of the linearized Navier-Stokes equations. The proposal is to the primary stability based on 2D eigenvalue problem for a compressible laminar separation bubble. The base flow is two-dimensional and is built through direct numerical simulations. The analysis will be supported by the technical and computational tools already developed.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GENNARO, E. M.; SOUZA, B. D. P.; RODRIGUEZ, D.. The effect of compressibility on the primary global instability of unforced laminar separation bubbles. Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 41, n. 12, DEC 2019. (15/26759-9, 17/01586-0)