Tool for Blade Stress Estimation during Multiple Simultaneous Vibratory Mode Responses

ABSTRACT: NextGen Aeronautics, leveraging past experience in generating stress spectra from static and vibratory loads as well as knowledge of gas turbines, is proposing a method for estimating blade stresses from multiple vibratory loads in rotating systems from limited manufacturer data from Campbell diagrams and strain gage blade stresses. The method hinges on utilizing 3D parametric generic integrally bladed rotor and single blade models, extracting lower order equivalent models and tuning the lower order models to reproduce the manufacturer modal data and forced response multi-modal stresses on discrete or all locations on a blade. Additionally, uncertainty bounds on the stresses will be provided to life estimation predictions. An easy-to-use software application will be developed for the entire generic model development and stress extraction and integrated into a commercial-of-the-shelf CAE pre and post processor. Our team consists of experts in dynamics and vibration and has strong support from P&W for the technology transition phase. BENEFIT: The technology finally developed in this program will directly benefit safe operation of gas turbines in the aviation industry as well as industrial steam and wind turbines, through better estimation of stresses generated from multiple vibratory loads. Costly re-designs from pre-mature failures in ground and flight test programs will be avoided and will aid in intelligent inspection intervals for safe operation of rotating systems.