Results 31 to 40 of about 587,209 (299)
Mathematical modeling and investigating the effect of the area of the horizontal stabilizer on the stability of a single-main-rotor helicopter in forward flight [PDF]
مجله مدل سازی در مهندسی, 2019 This paper investigates the effect of the area of the horizontal stabilizer of a single-main-rotor helicopter on its dynamic responses, stability properties, and flight handling quality during forward flights.
Fatemeh Ghaderi, Farid Shahmiri
doaj +1 more source
Improvement of the aerodynamic performance by wing flexibility and elytra--hind wing interaction of a beetle during forward flight. [PDF]
J R Soc Interface, 2013 Le TQ +6 more
europepmc +2 more sources
Safety, 2022 Helicopters are more and more widely used for water dumping in fire extinguishing operations nowadays. Increasing attention is being paid to improving helicopter firefighting efficiency.
Tejun Zhou +3 more
doaj +1 more source
A Numerical Study of the Sound and Force Production of Flexible Insect Wings
Fluids, 2018 We numerically solved the acoustic and flow field around cicada wing models with parametrically varied flexibility using the hydrodynamic/acoustic splitting method. We observed a gradual change of sound directivity with flexibility.
Biao Geng +4 more
doaj +1 more source
Paddling Mode of Forward Flight in Insects
Physical Review Letters, 2011 By analyzing high-speed video of the fruit fly, we discover a swimminglike mode of forward flight characterized by paddling wing motions. We develop a new aerodynamic analysis procedure to show that these insects generate drag-based thrust by slicing their wings forward at low angle of attack and pushing backwards at a higher angle.
Leif, Ristroph +4 more
openaire +3 more sources
Single rotor helicopter parasite drag estimation in the preliminary design stage [PDF]
Tehnika, 2018 This paper presents the methodology for the rapid estimation of the single rotor helicopter parasite drag in the forward flight in the preliminary design phase.
Dodić Marjan D. +2 more
doaj
Resolution of a paradox: Hummingbird flight at high elevation does not come without a cost [PDF]
, 2004 Flight at high elevation is energetically demanding because of parallel reductions in air density and oxygen availability. The hovering flight of hummingbirds is one of the most energetically expensive forms of animal locomotion, but hummingbirds are ...
Altshuler, Douglas L. +2 more
core +3 more sources
Transient Thrust Analysis of Rigid Rotors in Forward Flight
Aerospace, 2022 The purpose of this study was to investigate and quantify the transient thrust response of two small rigid rotors in forward flight. This was accomplished using a distributed doublet-based potential flow method, which was validated against wind-tunnel ...
Travis Krebs +2 more
doaj +1 more source
Flap‐Lag‐Torsion Stability in Forward Flight [PDF]
Journal of the American Helicopter Society, 1985 An aeroelastic stability of three-degree flap-lag-torsion blade in forward flight is examined. Quasisteady aerodynamics with a dynamic inflow model is used. The nonlinear time dependent periodic blade response is calculated using an iterative procedure based on Floquet theory.
Brahmananda Panda, Inderjit Chopra
openaire +1 more source
Annals of Clinical and Translational Neurology, EarlyView.ABSTRACT Background Accessing brain magnetic resonance imaging (MRI) can be challenging, especially for underserved patients, which may lead to disparities in neurological diagnosis. Method This mixed‐methods study enrolled adults with one of four neurological disorders: mild cognitive impairment or dementia of the Alzheimer type, multiple sclerosis ...
Maya L. Mastick +19 more
wiley +1 more source