Session: 28-06 System Dynamics & Identification Methods

Paper Number: 101107

101107 - Open Nasa Blade Models for Nonlinear Dynamics Simulations 

Nonlinear dynamic simulations, now required in the blade design process, are highly sensitive to variations of the blade geometries. Realistic industrial blade models are thus required to develop and validate methodologies related to nonlinear vibration phenomena. However, for confidentiality issues, blade geometries are rarely made available by aircraft engines manufacturers.

To address this issue, this contribution presents a catalogue of open turbomachinery blade models dedicated to nonlinear dynamics simulations. Based on a specifically developed in-house computer code, 3D geometries and finite element models of multiple-circluar-arc NASA airfoils are generated. Both the code and the models are made freely accessible online. To cover a wide range of geometries, 40 blades are considered from different stages and with different aspect ratios. The compressor blade rotor 37 and the fan blade rotor 67, recently used in the context of nonlinear structural interactions, are included. It is expected that this blade catalogue will provide an opportunity for the direct comparison of recently developed methodologies relative to nonlinear vibration phenomena in turbomachines, including rubbing events and blade-tip/casing contacts. To this end, the paper also contains original results for some of the most emblematic NASA blades, with an emphasis on nonlinear interaction maps and a detailed presentation of redesign operations to mitigate high amplitude of vibrations when blade-tip/casing contacts occur.

A long-term goal of this contribution is to improve the reproductibily of research results and help to comply with recent requirements regarding availability of research data. As models and associated results are to be enriched with time, a deeper understranding of non linear phenomena may be expected by centralizing research results related to specific blade geometries.

Presenting Author: Solene Kojtych Polytechnique Montrã©Al

Presenting Author Biography: Post doctoral researcher

Authors:

Solene Kojtych Polytechnique Montrã©Al
Alain Batailly Polytechnique Montréal