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A Study on the Hydraulic Excitation Forces Using Transfer Function and Operational Measured Data for the Centrifugal Pump

전달함수와 진동응답 측정에 의한 원심펌프에서의 유체력 특성에 관한 연구

  • Published : 2000.08.01

Abstract

Operating excitation forces of the linear vibratory system are normally determined by direct measurement techniques using load cells, strain gauges, etc. But, hydraulic forces of the rotating turbomachinery such as centrifugal pumps are exerted on an impeller due to asymmety of the flow by the interaction between pump impeller and volute. So, investigations of wide range of hydraulic designs and geometric deviations are difficult by direct method. This paper presents a hybrid approach for fourier transformed operational excitation forces, which uses pseudo-inverse matrix of the transfer matrix for the system and the measured vibrational data with standard installed pump. The determination of the transfer function matrix is based on a linear rotor/stationary system and steady state harmonic response in finite element analysis. And, vibrational data is collected in both vertical and horizontal directions at inboard and outboard bearing housings. The results of the process may be enhanced by making acceleration measurements at many more locations than there are forces to be determined.

Keywords

Hydraulic Force;Double Suction Centrifugal Pump;Transfer Function;Pseudo-Inverse Matrix;FRF;Finite Element Analysis

References

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