Comparison of the full-potential and Euler formulations for computing transonic airfoil flows
A study involving four transonic airfoil computer codes, two FP and two Euler, has been performed. The major conclusions of the study are as follows: (1) the FP codes are faster than the Euler codes by about an order of magnitude based on CPU time on the Cray XMP; (2) the FP formulation loses accuracy as transonic flow develops, but entropy corrections yield FP solutions comparable to those of the Euler; (3) grid coarseness and type can be significant in affecting both accuracy and convergence characteristics; (4) the FP formulation must be more tightly converged than the Euler formulation for comparable levels of accuracy in the lift coefficient; and (5) in general, good accuracy for adequate meshes can be obtained with both formulations, irrespective of the solution method.
KeywordsAIAA Paper Lift Coefficient Grid Refinement Transonic Flow Euler Formulation
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