Today the numerical flow simulation is established - apart from wind tunnel and flight test - as an indispensable tool for the development of new and for the improvement of existing airplanes. During the last years in particular one succeeded in making the comparatively very costly Navier Stokes procedures industrially usable for various developments.
In Germany the national project MEGAFLOW brought forward the development and quality of the numerical computation of complex flow problems significantly. MEGAFLOW (1995-1998) was initiated by the first aviation research program of the Federal Government under the leadership of the DLR. A network from aircraft industry, the DLR and several universities was created with the goal of concentrating the development activities for numerical flow simulation on a central program system. Based on MEGAFLOW the Navier Stokes procedures FLOWer and TAU have been introduced into the aerodynamic design process at Airbus Germany and became standard tools. Also at EADS-M, EUROCOPTER and DLR the MEGAFLOW software is used intensively for various aerodynamic problems. The internationally recognized high efficiency and quality of those procedures contributed largely to this broad usage.
The MEGAFLOW network was established as an efficient open group of very closely co-operating partners and worked satisfactorily. The supplementing expertises and experiences of the different partners contributed substantially to the world-wide recognized success of the MEGAFLOW codes. Beside the concentration of the substantial national activities in particular a drastic reduction of the time between the production of new basic results and their application in the industrial environment could be achieved by the group. For many universities the MEGAFLOW software represents a platform for the advancement of physical models and for the investigation of complex flow processes.
Due to the constantly growing requirements, which result from both the development of future airplanes and the competitive position of the German aircraft industry, substantial need of specific improvements and advancements of the methods exists despite the high stage of maturity of the MEGAFLOW methods. Particularly in the areas of the numerical shape optimization and the multidiscipline simulation further activities are necessary, in order to be able to keep pace with the progressing developments in particular in the US. New, innovative methods of the optimization (among other things adjoint, one shot, genetic and evolutionary methods, neural networks), the numerical solution algorithms (among other things implicit procedures and adaptation techniques), the physical modelling (among other things 3D transition prediction and advanced turbulence models) and the multidisciplinary coupling must be developed, tested in the industrial practice and adapted if necessary. In the future typically applications with more than 10-15 million mesh points are to be treated. Thus a specific importance meaning is attached to the efficient utilization of low-priced parallel computers. In particular with the numerical optimization and the multidisciplinary time-exact simulation for the examination of critical flight conditions with extreme flight attitudes a constant parallelism of the numerical process chain is necessary. This sphere of activity is at present world-wide the subject of intensive research work.