Abstract: The present invention relates to an improved array of flow directing elements for incorporation in turbomachinery. In accordance with the present invention, an array of flow directing elements comprises a plurality of flow directing elements mounted to a rotor disk. The plurality of flow directing elements includes a first set of first flow directing elements whose natural vibration frequency has been modified by having material removed from a leading edge tip region and a second set of second flow directing elements whose natural vibration frequency has been modified by having material removed from a midspan leading edge region. The array may further comprise unmodified flow directing elements arranged with the modified flow directing elements.

Abstract: The present invention relates to an array of flow directing elements having increased flutter stability for use in turbomachinery devices. The array comprises at least one high frequency flow directing element and at least one low frequency flow directing element. In a preferred embodiment, the array comprises a plurality of alternating high frequency and low frequency flow directing elements. Each high frequency flow directing element has its three lowest frequency vibratory modes at least 2.0% higher in frequency than the three lowest frequency vibratory modes of each low frequency flow directing element. The array of the present invention has particular utility in a turbomachinery device as part of a rotor stage.

Abstract: The present invention relates to an array of flow directing elements for use in turbomachinery. The array comprises a plurality of flow directing elements arranged around a disk in a circular pattern having four quadrants. The flow directing elements in each quadrant are different in mass from the flow directing elements in each adjacent quadrant to reduce the tendency of the array to exhibit tuned absorbed behavior. Further, the number of flow directing elements in each quadrant are different from the number of flow directing elements in each adjacent quadrant to reduce stator vibration in the turbomachinery. Still further, centfrigual pull on the disk is equalized by assembling quadrants with lower flow directing element count from heavier flow directing elements.