• Journal of KSNVE
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• v.8 no.6
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• pp.1062-1068
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• 1998

This paper describes the vibration characteristics of a high head pump-turbine runner. with nine blades and an outer diameter of 4.410 mm. of the pumped storage power plant. Mode shapes and natural frequencies were obtained by means of both the finite element analysis and modal testing. both in air and in water. The natural frequencies in air were calculated using the finite element method by ANSYS software. In order to confirm calculation results. the natural frequencies and mode shapes of the runner were measured using a hydraulic exciter both in air and in water. Natural frequencies of the pump-turbine runner were found at 174. 310 Hz in air, and at 107. 184 Hz in water. The first mode shape is flat plate mode with two nodal diameter and the second one is also flat plate mode with three nodal diameter. It can be shown that the natural frequencies of the pump-turbine runner in water is reduced approximately 40 ％ due to additional mass effect. Natural frequencies in air predicted by ANSYS software are in good agreement with test results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.278-282
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• 1997

This paper describes results of modal testing for a high head pump-turbine runner of the Muju pumped storage power plant. The head of the pump-turbine is 601 m and the outside diameter of its runner is 4,410 mm. The modal testing was done for two conditions : 1) the runner in air ; 2) the runner in water. For both conditions, obtained are natural frequencies, corresponding mode shapes and damping ratios. From the testing, it is found that the natural frequencies of the pump-turbine runner in water is reduced approximately 40 % due to additional mass effect of the water.