Abstract
In this paper, a three-dimensional model for the dynamic analysis of a flywheel based on the finite element method is presented.
The static structure analysis for the model provides stress and strain distribution cloud charts. The modal analysis provides the basis of dynamic analysis due to its ability to obtain the natural frequencies and the vibration–made vectors of the first 10 orders.
The results show the main faults are attrition and cracks, while also indicating the locations and patterns of faults. The harmonic response simulation was performed to gain the vibration response of the flywheel under operation.
In this paper, we present a Hilbert–Huang transform (HHT) algorithm for flywheel vibration analysis. The simulation indicated that the proposed flywheel vibration signal analysis method performs well, which means that the method can lay the foundation for the detection and diagnosis in a reactor main coolant pump.
In this paper, a three-dimensional model for the dynamic analysis of a flywheel based on the finite element method is presented.The static structure analysis for the model provides stress and strain distribution cloud charts. The modal analysis provides the basis of dynamic analysis due to its ability to obtain the natural frequencies and the vibration–made vectors of the first 10 orders. The results show the main faults are attrition and cracks, while also indicating the locations and patterns of faults. The harmonic response simulation was performed to gain the vibration response of the flywheel under operation.
In this paper, we present a Hilbert–Huang transform (HHT) algorithm for flywheel vibration analysis. The simulation indicated that the proposed flywheel vibration signal analysis method performs well, which means that the method can lay the foundation for the detection and diagnosis in a reactor main coolant pump.
Keywords
Dynamic analysis; Hilbert–Huang transform; Main coolant pump flywheel
1. Introduction
Vibration monitoring is an important issue for the maintenance and safety of main coolant pumps. Operation data show that the flywheel is mostly prone to fault in actual operation, which affects the safety of the whole nuclear power plant. The critical process involved in vibration monitoring is to extract reliable features representative of the vibration signal of the flywheel.
2. Flywheel modeling
Before establishing a flywheel finite element model, we need to get a three-dimensional solid model first. For an uncomplicated model, the CAD modeling method is generally applied. The model is then imported into the ANSYS geometry module through the software interface [1]. In this study, the solid flywheel model was established using Pro/E, then imported into ANSYS. In order to clarify the entire process, Fig. 1 shows the flow chart of the modeling and analysis.
The flywheel is composed of six parts: hub, heavy tungsten segments (HTS), shrink ring, end ring, sleeve, and thrust plate. The sectional view is shown in Fig. 2.
Sectional view of the flywheel.
Figure options
The axisymmetric model can be established by stretching, rotating, and arraying procedure. Fig. 3 depicts the exploded solid model established by Pro/E according to the structural parameters of the flywheel.