Study of laminar separation bubble on low Reynolds number operating airfoils: RANS modelling by means of an high-accuracy solver and experimental verification

31st UIT (Italian Union of Thermo-fluid-dynamics) Heat Transfer Conference 2013

Crivellini, A.^1 ; D'Alessandro, V.^1 ; Di Benedetto, D.^1 ; Montelpare, S.^2 ; Ricci, R.^1

Dipartimento di Ingegneria Industriale e Scienze Matematiche, Università Politecnica Delle Marche, Via Brecce Bianche, 60100 Ancona (AN), Italy^1

Dipartimento di Ingegneria, Geologia Università Degli Studi G. d'Annuzio di Chieti-Pescara, Viale Pindaro 42, Pescara (PE) 65127, Italy^2

关键词: Complex engineering;    Computational fluid dynamics simulations;    Discontinuous galerkin;    Experimental verification;    Laminar separation bubble;    Partial differential equations (PDE);    Reynolds-Averaged Navier-Stokes;    Subsonic wind tunnels;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/501/1/012024/pdf
DOI  :  10.1088/1742-6596/501/1/012024

来源: IOP

【 摘 要 】

This work is devoted to the Computational Fluid-Dynamics (CFD) simulation of laminar separation bubble (LSB) on low Reynolds number operating airfoils. This phenomenon is of large interest in several fields, such as wind energy, and it is characterised by slow recirculating flow at an almost constant pressure. Presently Reynolds Averaged Navier-Stokes (RANS) methods, due to their limited computational requests, are the more efficient and feasible CFD simulation tool for complex engineering applications involving LSBs. However adopting RANS methods for LSB prediction is very challenging since widely used models assume a fully turbulent regime. For this reason several transitional models for RANS equations based on further Partial Differential Equations (PDE) have been recently introduced in literature. Nevertheless in some cases they show questionable results. In this work RANS equations and the standard Spalart-Allmaras (SA) turbulence model are used to deal with LSB problems obtaining promising results. This innovative result is related to: (i) a particular behaviour of the SA equation; (ii) a particular implementation of SA equation; (iii) the use of a high-order discontinuous Galerkin (DG) solver. The effectiveness of the proposed approach is tested on different airfoils at several angles of attack and Reynolds numbers. Numerical results were verified with both experimental measurements performed at the open circuit subsonic wind tunnel of Universita Politecnica delle Marche (UNIVPM) and literature data.