Implicit Large Eddy Simulation of transition to turbulence at low Reynolds numbers using a Discontinuous Galerkin method

• Published in: International journal for numerical methods in engineering 2011-07, Vol.87 (1-5), p.232-261
• Main Authors: Uranga, A., Persson, P.-O., Drela, M., Peraire, J.
• Format: Article
• Language: English
• Subjects: Computational fluid dynamics; Computational methods in fluid dynamics; Discontinuous Galerkin method; Exact sciences and technology; Fluid dynamics; Fluid flow; Fundamental areas of phenomenology (including applications); Galerkin methods; Implicit Large Eddy Simulation; Laminar; Laminar boundary layers; Laminar flows; laminar separation bubble; Low Reynolds number; Mathematics; Numerical analysis; Numerical analysis. Scientific computation; Partial differential equations, initial value problems and time-dependant initial-boundary value problems; Physics; Reynolds number; Sciences and techniques of general use; transition to turbulence; Turbulence; Turbulence simulation and modeling; Turbulent flow; Turbulent flows, convection, and heat transfer
• ISSN: 0029-5981; 1097-0207; 1097-0207
• DOI: 10.1002/nme.3036

The present work predicts the formation of laminar separation bubbles at low Reynolds numbers and the related transition to turbulence by means of Implicit Large Eddy Simulations with a high‐order Discontinuous Galerkin method. The flow around an SD7003 infinite wing at an angle of attack of 4° is considered at Reynolds numbers of 10 000, 22 000, and 60 000 in order to gain insight into the characteristics of the laminar and turbulent regimes. At the lowest Reynolds number studied, the flow remains laminar and two dimensional over the wing surface, with a periodic vortex shedding. For higher Reynolds numbers, the flow is unsteady over the upper wing surface and exhibits a separation bubble along which the flow transitions to turbulence. Tollmien–Schlichting (TS) waves are observed in the boundary layer, and transition is found to be caused by unstable TS modes as revealed by the growth of the stream‐wise amplification factor. Copyright © 2010 John Wiley & Sons, Ltd.