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Actuator Feasibility Study for Active Control of Ducted Axial Fan NoiseA feasibility study was performed to investigate actuator technology which is relevant for a particular application of active noise control for gas turbine stator vanes. This study investigated many different classes of actuators and ranked them on the order of applicability. The most difficult requirements the actuators had to meet were high frequency response, large amplitude deflections, and a thin profile. Based on this assessment, piezoelectric type actuators were selected as the most appropriate actuator class. Specifically, Rainbows (a new class of high performance piezoelectric actuators), and unimorphs (a ceramic/metal composite) appeared best suited to the requirements. A benchtop experimental study was conducted. The performance of a variety of different actuators was examined, including high polymer films, flextensional actuators, miniature speakers, unimorphs, and Rainbows. The displacement/frequency response and phase characteristics of the actuators were measured. Physical limitations of actuator operation were also examined. This report includes the first known, high displacement, dynamic data obtained for Rainbow actuators. A new "hard" ceramic Rainbow actuator which does not appear to be limited in operation by self heating as "soft" ceramic Rainbows was designed, constructed and tested. The study concludes that a suitable actuator for active noise control in gas turbine engines can be achieved with state of the art materials and processing.
Document ID
Document Type
Contractor Report (CR)
Simonich, John C.
(United Technologies Corp. East Hartford, CT United States)
Date Acquired
September 6, 2013
Publication Date
December 1, 1994
Subject Category
Report/Patent Number
NAS 1.26:195412
Accession Number
Funding Number(s)
PROJECT: RTOP 538-03-11
Distribution Limits
Work of the US Gov. Public Use Permitted.
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