Dynamics analysis of fluid-conveying pipes with a nonparametric model
CAO Jianhua1,2,LIU Yongshou1,LIU Wei1
1.School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi’an 710029, China;
2.College of Mechanical and Electrical Engineering, Huangshan University, Huangshan 245021， China
In order to model the uncertainty of clamps of a pipeline in the aviation industry, a nonparametric method was adopted to model, simulate and predict the vibration characteristics of a fluid-conveying pipe.The clamp was modelled as simply supported and attached with a torsion spring.The wavelet-based finite element method was used to discretize the governing differential equations of the fluid-conveying pipe with clamps at two ends.The random global stiffness matrix, which models the effect of uncertainties of clamps, was generated by the nonparametric method.As shown in the numerical results, the confidence interval of the frequency response curves of the nonparametric model contains the mean model’s curves perfectly.As the frequency increases, the greater the influence of uncertainty at higher frequencies.For the case of the first four frequencies varying with the fluid velocity, the confidence interval of the curves of nonparametric model also contains the mean model’s curves perfectly.With the fluid velocity increasing, the influence of uncertainty on the real part of frequencies becomes smaller while the influence of uncertainty on the imaginary part of frequencies becomes greater.However, the uncertainty has no effect on the divergence and flutter instability.
曹建华1,2，刘永寿1，刘伟1. 航空输流管道动力学的非参模型研究[J]. 振动与冲击, 2018, 37(18): 43-47.
CAO Jianhua1,2,LIU Yongshou1,LIU Wei1. Dynamics analysis of fluid-conveying pipes with a nonparametric model. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(18): 43-47.
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