Computational Fluid Dynamics (CFD) has made remarkable progress in the last two decades and is becoming an important, if not inevitable, analytical tool for both fundamental and practical fluid dynamics research. The analysis of flow fields is important in the sense that it improves the researcher's understanding of the flow features. CFD analysis also indirectly helps the design of new aircraft and/or spacecraft. However, design methodologies are the real need for the development of aircraft or spacecraft. They directly contribute to the design process and can significantly shorten the design cycle. Although quite a few publications have been written on this subject, most of the methods proposed were not used in practice in the past due to an immature research level and restrictions due to the inadequate computing capabilities. With the progress of high-speed computers, the time has come for such methods to be used practically. There is strong evidence of a growing interest in the development and use of aerodynamic inverse design and optimization techniques. This is true, not only for aerospace industries, but also for any industries requiring fluid dynamic design. This clearly shows the matured engineering need for optimum aerodynamic shape design methodologies. Therefore, it seems timely to publish a book in which eminent researchers in this area can elaborate on their research efforts and discuss it in conjunction with other efforts.

It is a joyful and ?tting moment that we, the friends, colleagues and suppo- ers of Prof. Kunio Kuwahara, dedicate this Workshop to Prof. Kuwahara. We gathered in late April of 2003 in the tranquility of Nobeyama mountain resorttocommemoratethe60thbirthdayofProf.Kuwaharawhichhadfallen in November, 2002. IntheculturalbackdropofEastAsia,the60thbirthdaycarriesadditional signi?cance. Looking back on the occasion of Kan-re-ki (the 60th birthday), a man is supposed to have accomplished something of meaningfulness and value. With these undertones, it will be a useful exerciseto recount the spl- did accomplishments of Prof. Kuwahara. The major professional achievements of Prof. Kuwahara may be c- pressed into two main categories. First and foremost, Prof. Kuwahara will long be recorded as the front-line pioneer in using numerical computations to tackle complex problems in ?uid mechanics. His unquenching zeal in com- tation and utilization of computers is unmatched throughout the globe. His infatuation with the Supercomputers of 1980's and 1990's is now a legend in the ?uid dynamics communities. He continues to stand tall on the leading edge of computational ?uid mechanics research and industrial applications. In short, Prof. Kuwahara has ?lled in a chapter in the history of modern ?uid dynamics research.

Supercomputer technologies have evolved rapidly since the first commercial-based supercomputer, CRAY-1 was introduced in 1976. In early 1980's three Japanese super computers appeared, and Cray Research delivered the X-MP series. These machines including the later-announced CRAY-2 and NEC SX series created one generation of supercomputers, and the market was spread dramatically. The peak performance was higher than 1 GFLOPS and the compiler improvement was remarkable. There appeared many articles and books that described their architecture and their performance on The late 1980's saw a new generation of supercomputers. several benchmark problems. Following CRAY Y-MP and Hitachi S-820 delivered in 1988, NEC announced SX-3 and Fujitsu announced the VP2000 series in 1990. In addition, Cray Research announced the Y-MP C-90 late in 1991. The peak performance of these machines reached several to a few ten's GFLOPS. The hardware characteristics of these machines are known, but their practical performance has not been well documented so far. Computational Fluid Dynamics (CFD) is one of the important research fields that have been progressing with the growth of supercomputers. Today's fluid dynamic re search cannot be discussed without supercomputers and since CFD is one of the im portant users of supercomputers, future development of supercomputers has to take the requirements of CFD into account. There are many benchmark reports available today. However, they mostly use so called kernels. For fluid dynamics researchers, benchmark test on real fluid dynamic codes are necessary."