Dry Friction Interblade Damping by 3D FEM Modelling of Bladed Disk: HPC Calculations Compared with Experiment

Luděk Pešek,Vítězslav Bula,Pavel Šnábl,Miguel De Matos Neves

doi:10.1155/2021/5554379

Luděk Pešek, Vítězslav Bula + Show 2 more

Open Access

https://doi.org/10.1155/2021/5554379

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Abstract

Interblade contacts and damping evaluation of the turbine bladed wheel with prestressed dry friction contacts are solved by the 3D finite element method with the surface-to-surface dry friction contact model. This makes it possible to model the space relative motions of contact pairs that occur during blade vibrations. To experimentally validate the model, a physical model of the bladed wheel with tie-boss couplings was built and tested. HPC computation with a proposed strategy was used to lower the computational time of the nonlinear solution of the wheel resonant attenuation used for damping estimation. Comparison of experimental and numerical results of damping estimation yields a very good agreement.

Highlights

The turbines and their bladings can be carefully designed, it is not possible to omit resonant vibration leading to a high-cycle fatigue risk. e bladed wheel with sufficient dissipation of mechanical energy is the protection against this case
We focused on two critical wheel speeds with different modes of vibration, i.e., modes with 2 and 6 nodal diameters (ND)
The force vectors were specified at two nodes of the tie-boss prism of each blade around the circumference. e total static displacements (m) of the wheel computed for the 2ND, 6ND, and their modal force distributions are shown in Figures 11(b) and 12(b), respectively. e ascertained deformation modes were used as initial displacement conditions for the transient analysis

Summary

Introduction

The turbines and their bladings can be carefully designed, it is not possible to omit resonant vibration leading to a high-cycle fatigue risk. e bladed wheel with sufficient dissipation of mechanical energy is the protection against this case. E study deals with our latest research aimed at dry friction damping in the tie-boss contacts (Pesek et al [37,38,39]), where bladed wheel systems are numerically described by the 3D finite element method with dynamical contact problem.

Results

Conclusion