Integrated Smart Turbomachinery Blades for Cooperative Vibration Reduction
Abstract
The proposed basic science effort seeks to tailor turbomachinery bladed disk structural propertiesin real-time to avoid the vibrati"on that leads to catastrophic structural failure. Ultimately, thisresearch will lead to autonomous cooperative vibration reduction"" across an entire bladed disk.With embedded piezoelectric material distributed across each blade, this research will generatepatch" recruitment and switching strategies that optimally switch each blade stiffness to reducetransient resonant vibration across blade modes and the entire disk.Resonance frequency detuning is a self-powered autonomous technique that reduces vibration bymomentaril"y detuning the structural resonance from that of the excitation. This structural switchingis extremely low-power, only enough to th"row a switch; the electromechanical coupling ofpiezoelectric materials provides the corresponding change in stiffness. The PI~s previous researchon resonance frequency detuning demonstrated the method~s potential. Reduced vibration limitsfatigue and increases b"lade life. More fundamentally, it can allow increased aerodynamic forcesassociated with higher stage pressure ratios or boundary la""yer ingestion; alternatively, it can allowthinner blades for increased aerodynamic efficiency.Previous resonance frequency detunin""g research has largely treated resonance and excitationfrequency crossings in isolation, nominally as SDOF and beam-type vibratory" systems. This effortwill address remaining fundamental questions and produce a more complex framework forintegration in turbomach"inery. A key unknown at this point is how much coupling is achievable,and with what amount of piezoelectric material in a blade. Th"is effort will examine how to locateand orient the piezoelectric material in a distributed manner across a blade to maximize theelectromechanical coupling (and thus vibration reduction) across modes. It will also incorporate ashear lag model to answer how strain transfers to embedded piezoelectric materials and theassociated impact on vibration reduction performance. The proposed effort also will couple inplanemembrane loading to examine how rotation and centrifugal loading alter blade mode shapesand that effect on c"oupling. Using models with high modal density, this research will address howdetuning impacts vibration both in nearby modes and on"" other blades. It will then show how toexploit that information to improve detuning via switching that is cooperative, both in the" sense ofaddressing multiple closely-space vibration modes as well as addressing vibration on multipleblades.The PI is the ideal candidate to complete this basic science project. He introduced the concept ofresonance frequency detuning and has been researching blade vibration reduction for almost adecade. The PI has successfully conducted previous research with ONR and turbomachineryrelatedindustry as demonstrated by his publication record and awards ~ the past ONR projectresulted in four peer-reviewed papers and a"nother four articles in review, with approximately tenmore conference (abstract-reviewed) papers. He is also active with more appli"ed research projectson turbomachinery vibration with Siemens Energy and Alstom Power (now Ansaldo Energia).
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 05, 2017
- Source ID
- N000141712527
Entities
People
- Jeffrey Kauffman
Organizations
- Office of Naval Research
- United States Navy
- University of Central Florida Board of Trustees