Numerical Shape Optimization of Natural Laminar Flow Bodies
Th. Lutz and S. Wagner
Proceedings of the 21st ICAS Congress, September 13-18, 1998, Melbourne, Australia
An efficient calculation method for viscous incompressible flow prediction about axisymmetric bodies has been coupled with a hybrid optimizer and an evolution strategy. The coupled tool was employed to perform numerical shape optimizations of natural laminar flow bodies for various Reynolds number regimes. Contrary to the usual approach, the body geometry is not optimized in a direct way with the present method. Instead, a source singularity distribution on the axis is used to model the body contour and the corresponding inviscid flow field. Viscous effects are considered by means of an integral boundary-layer procedure. The reliable and consistent transition prediction is of essential importance for a successful shape optimization of laminar bodies. Therefore, a proved e^n criterion is applied in the present investigations.