317 Optimal Design of Compressor Blade Taking Account of Frequency Deviation

Recently, in order to improve performance of gas turbine's compressor, the thickness of compressor blade has become thinner. Therefore, for the purpose of increasing reliability, the blade's natural frequencies should be predicted precisely. In the compressor blade design, many natural frequencies must be tuned so as not to resonate with the frequencies of the excitation force under the constrained conditions which come from the requirements of manufacturing and performance. In this paper, an effective auto-tuning technique of the blade's natural frequencies is presented by combining Taguchi method with optimization method under constrained conditions and its application is shown. The new optimal technique in this paper is very useful in such blade design because the blade frequencies are automatically optimized, and at the same time the expected frequency deviations due to manufacturing tolerance are minimized. The calculated results show this method proposed can be applied to robust design of actual compressor blade.