Higher-order unstructured finite volume RANS solution of turbulent compressible flows. (17th January 2017)

• Record Type: Journal Article
• Authors: Jalali, Alireza; Ollivier-Gooch, Carl
• Is Part Of: Computers & fluids. Volume 143(2017)
• Page Start: 32
• Page End: 47
• Publication Date: 2017-01-17
• Subjects: Higher-order -- Finite-volume -- Unstructured meshes -- Turbulent flows -- RANS simulations; Fluid dynamics -- Data processing -- Periodicals; 532.050285
• DOI: 10.1016/j.compfluid.2016.11.004
• Languages: English
• ISSNs: 0045-7930

Abstract

Highlights: A higher-order finite volume method is developed for RANS simulations on unstructured meshes. A solution reconstruction strategy on curvilinear coordinates is devised for anisotropic meshes. The new reconstruction scheme highly improves solution accuracy. Higher-order discretizations deliver a more accurate solution with fewer degrees of freedom. Fast and efficient convergence to steady-state is obtained for higher-order methods. Abstract: In this paper, we describe a higher-order finite volume solver for the RANS solution of turbulent compressible flows on unstructured meshes. Considering that higher-order least-squares reconstruction suffers from poor accuracy on highly anisotropic meshes with curvature, we propose a modification to this method which highly improves the accuracy of solution approximation and output quantities. In addition, robust implementation and coupling of a RANS turbulence model with a higher-order finite volume solver is described and an efficient solution strategy is adopted for the convergence to the steady-state solution. We present our results, ranging from second- to fourth-order, for the test case of turbulent flat plate, subsonic and transonic flows over two-dimensional airfoils and also turbulent flow over a multi-element configuration. These results are verified by comparison against well-established numerical and experimental values in the literature. Our results show the advantages of higher-order methods in obtaining a more accurate solution with fewer degrees of freedom and also fast and efficient convergence to the steady-state solutions.