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EPTT 2024
14th Spring School on Transition and Turbulence
Investigation of Spanwise Periodic Transitional Airfoil Flows Using the Lattice-Boltzmann Method
Submission Author:
Cayan Antunes Dantas , SP , Brazil
Co-Authors:
Cayan Antunes Dantas, Bernardo Luiz Rocha Ribeiro, William Wolf
Presenter: Cayan Antunes Dantas
doi://10.26678/ABCM.EPTT2024.EPT24-0044
Abstract
The present study evaluates 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 3 deg, freestream Mach number of 0.3, and Reynolds number Re = 50,000. 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.
Keywords
Lattice Boltzmann, Transitional flow, Laminar separation bubble
