Unsteady vorticity-streamfunction algorithm for external flows
A non-inertial vorticity-streamfunction algorithm of the Reynolds-averaged Navier-Stokes equations is developed for studying unsteady and turbulent flows past airfoils. The equations are solved on a nonorthogonal C-grid using a combined finite-difference/finite-volume technique. Comparative computations are carried out employing three different turbulence models. These are the algebraic zero-equation model of Baldwin and Lomax [1], and the one-equation models of Baldwin and Earth [2] and Spalart and Allmaras [3]. The performance of the models is evaluated against experiments of the Aerospatiale-A airfoil at incidences up to 40 degrees and against two cases of an oscillating NACA 0015 airfoil experiencing light and deep stall. The computations demonstrate that the vorticity-streamfunction formulation combined with standard eddy-viscosity turbulence models is capable of predicting accurately unsteady and turbulent flows past airfoils. (C) 2000 Elsevier Science Ltd. All rights reserved.
vorticity-streamfunction navier-stokes equations unsteady flow