Order-Tuned Vibration Absorbers for Cyclic Rotating Flexible Structures

BackgroundBladed Disk Assemblies

BackgroundEngine Order Excitation

Conditions for ResonanceBackground

BackgroundVibration Reduction via Order-Tuned Absorbers

Background Self-tuning Impact Damper

Tuned Dampers

Sleeves

Chamber & End Caps

Turbine Blade

Vibration CharacteristicsFree Vibration – One DOF/Sector

Vibration CharacteristicsFree Vibration – One DOF/Sector

Vibration CharacteristicsFree Vibration – One DOF/Sector

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Vibration CharacteristicsFree Vibration – One DOF/Sector

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Vibration CharacteristicsFree Vibration – One DOF/Sector

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Mathematical ModelBladed Disk Assembly with Absorbers

Mathematical ModelLinearized System Model

Modal AnalysisBlock Decoupling the EOM

Modal AnalysisSteady-State Modal Response

Modal AnalysisSteady-State Modal Response

Modal AnalysisSteady-State Modal Response

Special Cases

1. Blades Locked, Absorbers Free

– Gives Absorber Tuning Order

2. Blades Free, Absorbers Locked

– A Benchmark to evaluate absorber performance

3. Single Isolated Sector, Blade/Absorber Free

– Demonstrates the essential features of the full coupled system

Special Case 1Blades Locked, Absorbers Free

Special Case 2Blades Free, Absorbers Locked

Special Case 2Blades Free, Absorbers Locked

Special Case 3Single Isolated Sector, Blade/Absorber Free

Special Case 3Single Isolated Sector, Blade/Absorber Free

Special Case 3Single Isolated Sector, Blade/Absorber Free

Special Case 3Single Isolated Sector, Blade/Absorber Free

Special Case 3Single Isolated Sector, Blade/Absorber Free

Special Case 3Single Isolated Sector, Blade/Absorber Free

N = 10 Sectors, Blades/Absorbers FreeLinear Forced Response

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Linear Forced Response

MOVIE

Linear Forced ResponseThe Effects of Detuning: No-Resonance Gap

Linear Forced ResponseSummary of Frequency Response

Summary• Linear, Perfectly Periodic System• Blades/Absorbers: absorber effective• Eigenfrequency structure: no resonance zone

• Effects of damping• Effects of mistuning• General-path absorbers• Multi-DOF blade models

– Nonlinear effects– Intentional mistuning

Directions for Future Work