Numerical study of the effect of a geometric disturbance in turbulent flows

• Grant number: 14/07623-6
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2014
• End date: February 28, 2019
• Field of knowledge: Engineering - Aerospace Engineering - Aerodynamics
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: William Roberto Wolf
• Grantee: Luiz Augusto Camargo Aranha Schiavo
• Host Institution: Faculdade de Engenharia Mecânica (FEM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 13/07375-0 - CeMEAI - Center for Mathematical Sciences Applied to Industry, AP.CEPID
• Associated scholarship(s): 16/03985-6 - Numerical Investigation of Compressibility Effects in Turbulent Boundary Layers, BE.EP.DR

Abstract

Boundary layers have been studied for several decades and the research in this area remains extremely active, both experimentally and numerically. Advances in experimental techniques and in computational power are enabling a deeper understanding of the structures found in such flows. For both industrial and nature flows, it is common to find situations where there is a small perturbation along the wall of the geometry being analyzed. Such disturbances can appear as ripples that perturb the boundary layer. In nature, some of the examples are the air flowing over desert dunes, and river flows in the presence of other small ripples along the river bed. In industry, examples are related to flows over airfoils with ice formation, sediment accumulated inside closed ducts in petroleum production lines and, also, for flows inside drain lines, among others. The disturbance of the boundary layer introduces new scales into the problem, changing the way in which the velocities and stresses are distributed along the flow. These changes in the distributions of both velocity and stress are important in many engineering applications. Thus, the study of a turbulent perturbed boundary layer is of great practical interest and it is a major scientific challenge. The investigation of this problem using analytical techniques may be impractical for problems with arbitrary boundary layer disturbances. Experimental investigations have high costs and quantities are usually difficult to measure since the region of interest is very close to the wall. This project intends to investigate the velocity profiles, shear stress distributions, kinetic turbulent energy and Reynolds stress budgets, and pressure and velocity spectra. Furthermore, the correlations between those quantities will also be studied along the channel and in the direction normal to the wall. Large eddy simulations will be performed along with statistical analyses in order to investigate the effects of geometrical perturbations in turbulent boundary layers. (AU)

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)

SCHIAVO, LUIZ A. C. A.; WOLF, WILLIAM ROBERTO; AZEVEDO, JOAO LUIZ F.. Turbulent kinetic energy budgets in wall bounded flows with pressure gradients and separation. Physics of Fluids, v. 29, n. 11, NOV 2017. (13/07375-0, 13/03413-4, 16/03985-6, 14/07623-6)

SCHIAVO, LUIZ A. C. A.; JESUS, ANTONIO B.; AZEVEDO, JOAO L. F.; WOLF, WILLIAM R.. Large Eddy Simulations of convergent-divergent channel flows at moderate Reynolds numbers. INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW, v. 56, p. 137-151, DEC 2015. (13/07375-0, 13/03413-4, 14/07623-6)

Academic Publications

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

SCHIAVO, Luiz Augusto Camargo Aranha. Simulação de grandes escalas de escoamentos turbulentos incompressíveis e compressíveis na presença de paredes. 2019. Doctoral Thesis - Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica Campinas, SP.