
Vortex method with turbulence sub-grid scale modelling
Author(s) -
Luiz Antonio Alcântara Pereira,
Miguel Hiroo Hirata,
Aristeu Silveira Neto
Publication year - 2003
Publication title -
journal of the brazilian society of mechanical sciences and engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.431
H-Index - 40
eISSN - 1806-3691
pISSN - 1678-5878
DOI - 10.1590/s1678-58782003000200005
Subject(s) - turbulence , scale (ratio) , vortex , grid , physics , statistical physics , computer science , environmental science , mechanics , geology , geodesy , quantum mechanics
In this paper a method for the simulation of convection and diffusion of the vorticity, generated on a body surface is presented. A purely Lagrangian scheme is used for the vorticity convection, and thereby avoiding mesh associated problems. The body surface is simulated by straight-line panels, with constant-strength vortex distribution. The strength of the discrete vortices is obtained directly without going through any additional calculation. Using a primary diffusion process this vorticity is replaced by Lamb vortices located nearby the body surface. The diffusion process of the vorticity is simulated using the random walk scheme. Turbulence sub-grid scale modelling employs a Second Order Velocity Structure Function model adapted to the Lagrangian scheme. With a cloud of discrete vortices this velocity structure function model is employed to simulate the micro structures of the flow. The flow over a circular cylinder and a NACA 0012 aerofoil are considered to evaluate the integrated aerodynamic loads. Comparisons are made with previous theoretical and experimental studies