Results 91 to 100 of about 68,215 (317)
Aerodynamic and acoustic analysis of helicopter main rotor blade tips in hover [PDF]
, 2016 Purpose: The design of main rotor blade tips is of interest to helicopter manufactures since the tip details affect the performance and acoustics of the rotor. The paper aims to discuss this issue.
Barakos, George +4 more
core +1 more source
Contact Lens with Moiré Patterns for High‐Precision Eye Tracking
Advanced Functional Materials, EarlyView.This work presents a passive contact lens for high‐precision eye tracking, integrating a microscopic moiré grating label. The parallax‐induced shift of macroscopic moiré patterns enables angle measurement with 0.28° precision using a standard camera under ambient light.
Ilia M. Fradkin +11 more
wiley +1 more source
Surrogate Based Optimization of Aerodynamic Noise for Streamlined Shape of High Speed Trains
Applied Sciences, 2017 Aerodynamic noise increases with the sixth power of the running speed. As the speed increases, aerodynamic noise becomes predominant and begins to be the main noise source at a certain high speed.
Zhenxu Sun, Ye Zhang, Guowei Yang
doaj +1 more source
Rotor performance characteristics from an aeroacoustic helicopter wind-tunnel test program [PDF]
An investigation of helicopter rotor noise at model scale was conducted in the Langley 4 by 7 meter tunnel. The program described was the first of a planned three-phase project whose purpose was to examine the characteristic noise mechanism involved in ...
Elliott, J. W., Hoad, D. R., Orie, N. M.
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Apparatus for reducing aerodynamic noise in a wind tunnel [PDF]
, 1976 An apparatus is described for reducing the background noise produced by the porous walls of the test section of a wind tunnel. A finely meshed screen member is placed over the perforations in the test section walls.
Howard, P. W., Schutzenhofer, L. A.
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Advanced Functional Materials, EarlyView.Rational halogen mixing strategy was employed to shift the bandgap of Cs2PbBr2I2 from ultraviolet to visible region, enabling first realization of a visible‐light photodetector with this 2D layered Ruddlesden‐Popper perovskite material. Under illumination, light‐induced internal field forms and drives trap‐mediated persistent photoconductivity ...
Md Fahim Al Fattah +11 more
wiley +1 more source
Chengshi guidao jiaotong yanjiuObjectiveThe enclosure condition of undercarriage equipment directly affects the aerodynamic shape of the train, which in turn affects the aerodynamic performance of the whole train. Therefore, it is necessary to carry out a research on the impact of the
Keming SHANG +4 more
doaj +1 more source
Advanced Functional Materials, EarlyView.Multi‐metal Cu─Ce─Ag nanoparticles harness synergistic interactions to drive efficient electrochemical CO2 reduction reaction toward C2+ products at high current densities. Ag enhances CO production, Ce modulates Cu oxidation states, and together they boost *CO coverage and local pH to enhance C─C coupling, enabling record C2+ yields with suppressed ...
Nini Zhang +9 more
wiley +1 more source
Numerical Study on the Aerodynamic Performance and Noise of Composite Bionic Airfoils
FluidsBionic airfoils are an effective method to improve aerodynamic performance and reduce the noise of wind turbine blades. To explore the impact of the lower surface of bird wing airfoils on the aerodynamic performance and noise of blades, this study ...
Shunlong Su +3 more
doaj +1 more source
High Specification Offshore Blades: Work Package: 1B: Blades Design [PDF]
, 2008 This report outlines the current state of the art in offshore wind turbine blade aerodynamic design, along with the key technical limitations and possible technologies which may improve the aerodynamic design of blades and turbine rotors in the future ...
Brown, Richard +3 more
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