Large Composite fan blade development for modern aeroengines

摘要

The state of maturity of contemporary PMC's after almost 30 years of scientific and technology development has resulted in a capability that far exceeds that available in the late 1960's, and which, in 1989, prompted General Electric to engage in the notably successful development and flight certification of large PMC fan blades for their GE90 engine. In this paper an accounting of the specific enhancements in (i) constituent (fiber and matrix) property characteristics, (ii) fabrication and processing options, and (iii) design analysis methods combind with computational capabilities wil be discussed. However, an equally improtant aspect is the variation in the design options that has resulted from evolving high by-pass ratio engine technology, which will also be addressed. The GE90 fan blade represents one of these options, being a relatively large blade designed to operate at lower tip speeds, thereby reducing the severity of the impact threat represented by the ingestion of large birds. A comparison between various modern turbofan engine fan blades and othe rotor blades serves to indicate the important parameters and the difficulty of establishing a composite threshold range for rotor blades in general.