کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
655345 1457637 2013 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Active compliant wall for skin friction reduction
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Active compliant wall for skin friction reduction
چکیده انگلیسی


• Objective: Delay of laminar-turbulent transition on a wing by active wall actuation.
• Natural, convective TS-instabilities are damped by travelling counter waves.
• Piezo driven active wall and model predictive controller were developed.
• TS amplitudes were damped by 83.6% (equals 15.7 dB within instability band).
• Significant effect on skin friction distribution.

In order to reduce skin friction drag, an active laminarisation method is developed. Laminar-turbulent boundary layer transition caused by Tollmien–Schlichting (TS) waves is delayed by attenuation of these convective instabilities. An actively driven compliant wall is integrated as part of a wing’s surface. Different configurations of piezo-based actuators are combined with an array of sensitive surface flow sensors. Wall-normal actuation as well as inclined wall displacement are investigated. Together with a realtime-control strategy, transition onset is shifted downstream by six average TS-wave lengths. Using the example of flow velocity, the influence of variable flow conditions on TS-damping rates was investigated. Besides, the boundary layer flow downstream of the active wall area as well as required wall deflections and the global damping effect on skin friction are presented in this paper.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Fluid Flow - Volume 44, December 2013, Pages 87–94
نویسندگان
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