This paper is an attempt to overview some of the recent turbomachinery aeroelasticity methods as this research area has seen a very rapid rate of progress in the last five years or so. Indeed, it is now possible to couple Navier-Stokes representations of the unsteady flow with 3D finite element representations of the structure to undertake multi-passage, multi-row calculations for both turbine and compressor applications. The phenomenon of fan blade flutter is discussed in some detail with several illustrative examples. It is found that whole-assembly calculations arc becoming increasingly common. The geometric and acoustic effects of the intake duct are also identified to be significant factors in flutter stability. A small number of papers are reviewed in detail to highlight recent improvements in modelling capability. Current 3D methods to predict blade passing and low engine order forced response phenomena are surveyed next, again with some illustrative examples. Such techniques usually involve multi-passage, multi-row models and they also include features such as blade flexibility and blade root friction dampers. The results indicate that it is now possible to predict the forced vibration levels with reasonable accuracy. Although the area of low-engine order excitation is still poorly understood, initial results indicate that the investigative tools are now in place to study the effect of various flow non-uniformities arising from uneven stator blade spacing, flow exit angle, blocked burners, etc. Finally, an optimum meshing strategy is discussed for turbomachinery blades and the computational aspects of 3D aeroelasticity methods are discussed briefly.
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