scispace - formally typeset
Search or ask a question
Topic

Airfoil

About: Airfoil is a research topic. Over the lifetime, 24696 publications have been published within this topic receiving 337709 citations. The topic is also known as: aerofoil & wing section.


Papers
More filters
Proceedings ArticleDOI
05 Jan 2004
TL;DR: In this article, the authors present the results of experimental investigations that are directly related to recently published plasma phenomenology findings and show that plasmas do have predictable behavior and may be useful flow-control devices on future air vehicles.
Abstract: This work presents the results of experimental investigations that are directly related to recently published plasma phenomenology findings. Several parameters were varied during tests on a flat plate substrate in still air (bench tests) and validated on a thin airfoil at low speeds. The aim was to build robust dielectric barrier discharge plasma actuators with good performance characteristics over wide operating ranges. These parameters included the signal waveform, signal frequency, electrode geometry, as well as power dissipated by the plasma generating system. The bench tests confirmed that of the many types of signal waveforms tested, the positive sawtooth produced not only the highest plasma duty cycle but the most force per unit of power delivered to the actuator system. Varying signal frequencies between 3 and 10 kHz made little difference in the net force production, but exhibited peak performance at 5 kHz. Net reaction forces increased in a near linear relationship to input power over a wide range of moderate power settings once the plasma was initiated. Surprisingly, actuators with larger dielectric thicknesses produced greater net forces. Reaction forces in the direction along the substrate surface were more than an order of magnitude greater than reaction forces normal to the substrate surface. For the NACA 0015 airfoil tests, a single plasma actuator was placed at 7% chord. Test results showed that an optimized plasma actuator gave substantial increases in the lift and reductions in the drag beyond the baseline stall angle of attack. These investigations have shown that plasmas do have predictable behavior and may be useful flow-control devices on future air vehicles.

86 citations

Journal ArticleDOI
TL;DR: In this paper, the transduction of a piezoaeroelastic energy harvester under the combination of vibratory base excitations and aerodynamic loadings is investigated.

86 citations

Journal ArticleDOI
TL;DR: In this article, a detailed grid resolution study is presented for flow over a three-element airfoil and two turbulence models, a one-equation Baldwin-Barth model and a two equation k-omega model are compared.
Abstract: The current work presents progress in the effort to numerically simulate the flow over high-lift aerodynamic components, namely, multi-element airfoils and wings in either a take-off or a landing configuration. The computational approach utilizes an incompressible flow solver and an overlaid chimera grid approach. A detailed grid resolution study is presented for flow over a three-element airfoil. Two turbulence models, a one-equation Baldwin-Barth model and a two equation k-omega model are compared. Excellent agreement with experiment is obtained for the lift coefficient at all angles of attack, including the prediction of maximum lift when using the two-equation model. Results for two other flap riggings are shown. Three-dimensional results are presented for a wing with a square wing-tip as a validation case. Grid generation and topology is discussed for computing the flow over a T-39 Sabreliner wing with flap deployed and the initial calculations for this geometry are presented.

86 citations

Journal ArticleDOI
TL;DR: It is shown that accurate leading edge noise predictions can be made when assuming an inviscid meanflow, but that it is not valid to assume a uniform meanflow.
Abstract: Computational aeroacoustic methods are applied to the modeling of noise due to interactions between gusts and the leading edge of real symmetric airfoils Single frequency harmonic gusts are interacted with various airfoil geometries at zero angle of attack The effects of airfoil thickness and leading edge radius on noise are investigated systematically and independently for the first time, at higher frequencies than previously used in computational methods Increases in both leading edge radius and thickness are found to reduce the predicted noise This noise reduction effect becomes greater with increasing frequency and Mach number The dominant noise reduction mechanism for airfoils with real geometry is found to be related to the leading edge stagnation region It is shown that accurate leading edge noise predictions can be made when assuming an inviscid meanflow, but that it is not valid to assume a uniform meanflow Analytic flat plate predictions are found to over-predict the noise due to a NACA 0002 airfoil by up to 3 dB at high frequencies The accuracy of analytic flat plate solutions can be expected to decrease with increasing airfoil thickness, leading edge radius, gust frequency, and Mach number

86 citations

Journal ArticleDOI
TL;DR: In this article, the main objective of this paper is to categorize practical families of horizontal-axis wind turbine rotors, which are optimized to produce the largest possible power output.

86 citations


Network Information
Related Topics (5)
Reynolds number
68.4K papers, 1.6M citations
80% related
Boundary layer
64.9K papers, 1.4M citations
77% related
Laminar flow
56K papers, 1.2M citations
76% related
Rotor (electric)
179.9K papers, 1.2M citations
75% related
Vortex
72.3K papers, 1.3M citations
75% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231,083
20221,871
2021923
2020979
20191,097
20181,002