Non-harmonic deployment of trailing-edge flaps for rotor-performance enhancement and vibration reduction

Frank Kody, Ethan Corle, Mark David Maughmer, Sven Schmitz

Research output: Chapter in Book/Report/Conference proceedingConference contribution

11 Scopus citations

Abstract

A computational method involving a multi-objective evolutionary based optimizer is investigated which provides an optimal set of non-harmonic deployment schedules for a multi-segment, trailing-edge flap. The trailing-edge flap is added to the UH-60A's rotor, with the flap's span, deflection magnitudes, and start/end deployment azimuth positions all optimized to minimize the total power of the rotor and the three resulting hub force vibratory loads at a target flight condition of μ=0.30. Single-objective optimizations are carried out, prior to the multi-objective study, where the non-harmonic deployment schedule of a single and dual segment trailing-edge flap is optimized to minimize power required over a target flight envelope of 0.05 < μ < 0.37. The formal optimization effort is carried out through the coupling of a comprehensive analysis code, RCAS, and one of two evolutionary algorithm based optimizers, CMA-ES (single objective) and ε-MOEA (multi-objective). The single-objective investigations using the CMA-ES solver generated promising results. With regards to a single-segment flap, peak power savings over the flight envelope have reached 9.5% (at μ=0.30) with associated Fz and Fxy hub vibration reductions of 66% and 22%, respectively. The dual segment optimization yielded power savings of 8.9% at the same flight condition. Several representative points were selected from a pareto front created by the four-objective optimization effort to show how the optimized solutions can vary. One of these optimized solutions found a 6.7% power savings, 68% Fz hub vibration reductions, and a 53% Fxy hub vibration reductions. The interdisciplinary character between rotorcraft dynamics and aeromechanics of the computational method hence presents an innovative way of improving rotorcraft performance while also reducing vibratory loads.

Original languageEnglish (US)
Title of host publicationAmerican Helicopter Society International - 5th Decennial AHS Aeromechanics Specialists' Conference 2014
Subtitle of host publicationCurrent Challenges and Future Directions in Rotorcraft Aeromechanics
PublisherAmerican Helicopter Society International
Pages190-204
Number of pages15
ISBN (Electronic)9781634391788
StatePublished - Jan 1 2014
Event5th Decennial AHS Aeromechanics Specialists' Conference 2014: Current Challenges and Future Directions in Rotorcraft Aeromechanics - San Francisco, United States
Duration: Jan 22 2014Jan 24 2014

Publication series

NameAmerican Helicopter Society International - 5th Decennial AHS Aeromechanics Specialists' Conference 2014: Current Challenges and Future Directions in Rotorcraft Aeromechanics

Other

Other5th Decennial AHS Aeromechanics Specialists' Conference 2014: Current Challenges and Future Directions in Rotorcraft Aeromechanics
CountryUnited States
CitySan Francisco
Period1/22/141/24/14

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All Science Journal Classification (ASJC) codes

  • Aerospace Engineering

Cite this

Kody, F., Corle, E., Maughmer, M. D., & Schmitz, S. (2014). Non-harmonic deployment of trailing-edge flaps for rotor-performance enhancement and vibration reduction. In American Helicopter Society International - 5th Decennial AHS Aeromechanics Specialists' Conference 2014: Current Challenges and Future Directions in Rotorcraft Aeromechanics (pp. 190-204). (American Helicopter Society International - 5th Decennial AHS Aeromechanics Specialists' Conference 2014: Current Challenges and Future Directions in Rotorcraft Aeromechanics). American Helicopter Society International.