Assessment of Transitional Airfoil Flows through the Lattice-Boltzmann Method Part I: Spanwise Periodic Flows

Author(s)

Dantas, Cayan A. ; Ribeiro, Bernardo Luiz R. ; Wolf, William R.

• Document type: Journal article
• Source: AIAA AVIATION FORUM AND ASCEND 2024; v. N/A, p. 11-pg., 2024-01-01.

Abstract

The present study consists in the first of a two-part joint paper series, where we assess the capability of a lattice-Boltzmann high-fidelity simulation tool to resolve transitional flows with intermittent events. Here, the lattice-Boltzmann method (LBM) is employed to investigate the spanwise-periodic flow over a NACA0012 airfoil at an angle of attack of alpha = 3 degrees, freestream Mach number of M-infinity = 0.3, and Reynolds number Re = 5 x 10(4). For this particular case, a laminar separation bubble forms on the airfoil suction side, being responsible for a complex dynamics including the shedding of coherent structures that generate trailing-edge tonal noise. A grid convergence study is performed for the LBM and results are validated against large eddy simulations (LES) of the Navier-Stokes equations. Good comparisons are observed between the LBM and LES results in terms of time-averaged flow fields. Similar separation and reattachment locations are found for the suction side laminar separation bubble (LSB). An analysis in terms of the vortex dynamics is also presented, and different patterns of vortex shedding from the LSB are found, in agreement with LES results. In summary, the LBM approach is able to represent similar flow physics compared to the Navier-Stokes equations, but with around 10% of the computational cost of the LES. (AU)

• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 21/06448-0 - High-fidelity numerical simulations applied in unsteady aerodynamics, turbulence and aeroacoustics
• Grantee: William Roberto Wolf
• Support Opportunities: Research Grants - Young Investigators Grants - Phase 2
• FAPESP's process: 23/08768-7 - High-fidelity simulations of rotor configurations: Analysis of unsteady aerodynamics and aeroacoustics
• Grantee: Bernardo Luiz Rocha Ribeiro
• Support Opportunities: Scholarships in Brazil - Post-Doctoral