Vortex pairing aeroacoustics in assymetric wakes

• Grant number: 12/19810-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2013
• End date: December 31, 2013
• 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

The purpose of this study is to analyze the aeroacustics of asymmetric wakes. Such flow is composed by the combination of a symmetric wake and a shear flow. It can be found downstream from airfoils generating lift or from tubes close to a wall, for example. The flow evolution is computed by direct numeric simulation, in which controlled perturbations are induced, allowing the behavior of the flow to be calculated for various frequencies. Asymmetric vortex are formed and paired, both the formation and pairing generate sound. Due to the asymmetry, the sound propagates in a different manner for every direction. Studying the factors that influence in this distributions allows a better understanding of the aeroacustics of more complex bodies. In the future, such knowledge might be used in the engineering of quieter aircraft, fulfilling stricter environmental requirements.(AU)