A 2D CFD study of symmetrical airfoils part I: In isolated flow

Among the methods being investigated to extract energy from the waves is the oscillating water column, which is used in combination with the bi-directional, self-rectifying Wells turbine. The application of Computational Fluid Dynamics to the analysis of the aerodynamic characteristics of symmetrical airfoil blades in two-dimensional isolated flow was studied. The lift coefficients predicted by Fluent™ were all within ≤ 5% of the experimental results. For the Fluent™ model with the transition fixed at 5% chord, a laminar separation bubble occurred. The analysis with the fixed transition and the analysis with fully turbulent flow using the Reynolds Stress turbulence models gave the most accurate prediction for lift. Both the Reynolds Stress and the RNG κ-ε turbulence models over-predicted the pressure drag to the extent that it dominated the total drag force. Analysis of the different turbulence options in the software highlighted the ability of the Reynolds Stress Equation Model to give very accurate predictions of lift and drag, while the RNG κ-ε turbulence model was most effective in predicting the onset of trailing edge stall. This is an abstract of a paper presented at the 10th (2000) International Offshore and Polar Engineering Conference (Seattle, US, 5/28/-6/2/200).