Equivalent beam element method for stepped rotors based on the bending stiffness

ZHANG Weifeng; LI Dongjie; ZHANG Ke; ZHOU Ming

doi:10.16511/j.cnki.qhdxxb.2022.21.011

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Journal of Tsinghua University(Science and Technology) ›› 2022, Vol. 62 ›› Issue (12) : 2021-2028. DOI: 10.16511/j.cnki.qhdxxb.2022.21.011

MECHANICAL ENGINEERING

Equivalent beam element method for stepped rotors based on the bending stiffness

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Abstract

The accuracy of using beam elements to model the stresses in stepped rotors is improved in this study by using cone-shape equivalent beam elements with shapes based on the bending stiffness. The bending stiffness of sections with abrupt changes was calculated in ANSYS using 3-D solid elements. The optimal size of the equivalent beam element was obtained using a least squares procedure. The calculations were used to relate the equivalent beam element size to the stepped rotor size. The calculations also related the equivalent beam element size to the integral disk size. The accuracy of the equivalent beam size models was then verified by rotor dynamics analyses. The results show that the critical speeds obtained using the equivalent beam elements agree better with the reference values in this paper than the results of both traditional beam models without equivalent segments and the 45?equivalent beam method.

Key words

stepped rotor / disk / bending stiffness / equivalent beam element / rotor dynamics

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ZHANG Weifeng, LI Dongjie, ZHANG Ke, ZHOU Ming. Equivalent beam element method for stepped rotors based on the bending stiffness[J]. Journal of Tsinghua University(Science and Technology). 2022, 62(12): 2021-2028 https://doi.org/10.16511/j.cnki.qhdxxb.2022.21.011

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