Trends in CFD for Aeronautical 3-D Steady Applications: The Dutch Situation

Current and mid-term developments in computational 3-D steady aerodynamics software at NLR, focusing on the efficient aerodynamic design of the next generation of transport aircraft, are surveyed on a global level. Following a brief review of the various levels of sophistication in physical flow modelling, and their relation to the aerodynamic design process in general, the major aerodynamic problem areas that are at present accessible to computational aerodynamics are discussed. The coherence in computational methods develqpment is subsequently explained by showing how the methods cover a growing part of the aircraft operating range. Subsequently, the approach taken towards the development of the most advanced methods, based on the Euler and Reynolds-averaged Navier-Stokes equations, is discussed. Here the accents are on proven technology, uniformity of approach, block-structured boundary conforming grids, flexibility, robustness, and adaptive local grid refinement for physical relevance. It is shown that the developments discussed presuppose access to the computing power offered by the present and upcoming generation of modern vectorcomputers. Finally, the informatics aspects are discussed. It is explained, that the steadily growing amount of computational aerodynamics software needs definite measures to keep things under control. The general technical concept, which is currently being developed at NLR to stay in control, is briefly surveyed. This involves the management of methods as well as data, and the interaction with the user. Computers/workstations are embedded in an efficient communication network.