Enhancement of a viscous-inviscid-interaction airfoil analysis code using the parallel direct search algorithm

The coupling mechanism for an existing viscous-inviscid-interaction (VII) code, developed for the analysis of two-dimensional, turbulent, attached flow around airfoils, is enhanced using the parallel direct search (PDS) optimization algorithm. It is demonstrated that this parallel processing implemented optimization scheme leads to faster convergence of the VII code, and therefore, requires less computational time when the number of optimization (or design) variables is low, and a moderate number of processors are available. As the number of design variables increases, more processors are required to maintain this advantage. Results are presented for the NACA-0012 and the RAE-2822 airfoils. The quality of the results obtained is satisfactory and confirms that the enhanced VII code can be an acceptable alternative to reduced Navier-Stokes solvers as an airfoil analysis tool.