Equivalent beam element method for stepped rotors based on the bending stiffness
ZHANG Weifeng1,2, LI Dongjie1, ZHANG Ke1, ZHOU Ming1
1. School of Aerospace Engineering, Tsinghua University, Beijing 100084, China; 2. Department of Military Vehicle Engineering, Army Military Transportation University, Tianjin 300161, China
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.
张卫锋, 李东杰, 张可, 周明. 基于弯曲刚度的阶梯转子等效梁单元方法[J]. 清华大学学报（自然科学版）, 2022, 62(12): 2021-2028.
ZHANG Weifeng, LI Dongjie, ZHANG Ke, ZHOU Ming. Equivalent beam element method for stepped rotors based on the bending stiffness. Journal of Tsinghua University(Science and Technology), 2022, 62(12): 2021-2028.
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2022, Vol. 62 
