Abstract
This paper describes a theoretical investigation for a traveling mode state of turbine blade with one-ringed blade and grouped blade structures (compound periodic structure) when subjected to engine order excitation. In addition, a series of experiments with a simple blade model is performed by simulating engine order excitation under a non-rotating condition. Ceramic oscillators are attached to all the blades. Each blade is excited by a sinusoidal wave with an inter-blade phase angle corresponding to the traveling mode. As a result, traveling mode of the compound periodic structure was confirmed by a series of experiments with a simple blade model. The modes of nodal diameter components, which are included in a set of nodal diameters in a natural mode and not only related, but also unrelated to the harmonic excitation order, behave like the traveling mode.
