Results 191 to 200 of about 4,258 (219)

Coaxial Rotor Broadband Noise Prediction in Hover

Proceedings of the Vertical Flight Society 76th Annual Forum, 2020
This paper presents an efficient prediction of coaxial rotor broadband noise, particularly trailing-edge noise. The method combines a newly developed iterative coaxial rotor BEMT, a viscous panel method, an empirical wall pressure spectrum, and Amiet's trailing-edge noise model.
Seongkyu Lee, Inbal Shlesinger
openaire   +1 more source

Quantification of Swirl Recovery in a Coaxial Rotor System

Proceedings of the Vertical Flight Society 73rd Annual Forum, 2017
Experiments were performed in hover on a 2 m diameter, isolated single rotor system, a coaxial counter-rotating rotor (CCR) system, and coaxial co-rotating (stacked) rotor system to quantitatively extract the swirl recovery of a CCR system. The performance comparison was based on induced power factors obtained from curve fits to momentum theory.
Daiju Uehara, Jayant Sirohi
openaire   +1 more source

Wake of a Coaxial Corotating Rotor in Hover

AIAA Journal, 2022
John A. Valdez, Charles E. Tinney
openaire   +1 more source

Flight Dynamics of a Coaxial Compound Helicopter with Rotor-on-Rotor Interactional Aerodynamics

Journal of the American Helicopter Society
This paper focuses on the integration of a generalized rotor-on-rotor interactional aerodynamics model in state-variable form within a flight dynamics simulation and on its subsequent linearization and linear model analysis. The aircraft chosen for this investigation is a generic lift-offset compound coaxial rotorcraft.
Dogyu Jun, Alessandro Cocco, Umberto Saetti, Ondrej Juhasz   +3 more
openaire   +1 more source

Coaxial contrarotating twin rotor aerodynamics [PDF]

, 1983
The modelling of a Coaxial Contrarotating Twin Rotor (CCTR) system has been developed from single rotor modelling techniques. Particular attention has been paid to the characteristics of the tip vortex, namely, vortex strength, structure and decay. Equations are presented which describe both the vortex core and the complete structure of a rolled-up tip
openaire  

Design and Analysis of Coaxial Rotor Wind Turbine

2018
Wind turbine is one of the booming technologies to generate optimum electricity from renewable source at a most economical cost; the extraction of energy in the present era is already established and further enhanced to improve its efficiency. Coaxial wind turbine is a great rise in the technology of the wind rotor motors when trying to obtain ...
Sachin Manohar Shinde, Mohit Chaudhari, Tejas Jeurkar, Sanket Kadam, Kiran B. Salunkhe   +4 more
openaire   +1 more source

Auto-oscillations of coaxial rotors

Soviet Applied Mechanics, 1971
D. K. Ovcharova, E. G. Goloskolov
openaire   +1 more source

Analysis of the Dynamic Response of Coupled Coaxial Rotors

The fundamental dynamics of a single rotor are very well understood, and extensively covered in the literature. However, many rotating machines such as aircraft engines consist of multiple shafts, which are often directly coupled by inter-shaft bearings. This paper aims to provide better insight into the underlying dynamics of such systems by analysing
Alexander H. Haslam, Christoph W. Schwingshackl, Andrew I. J. Rix   +2 more
openaire   +1 more source

Predicting the aerodynamic noise of counter-rotating coaxial rotors

Journal of Sound and Vibration, 2023
Siyang Zhong, Zhida Ma, Peng Zhou
exaly  

Aeromechanics of a High Speed Coaxial Helicopter Rotor

2017
The current work seeks to understand the aeromechanics of lift offset coaxial rotors in high speeds. Future rotorcraft will need to travel significantly faster that modern rotorcraft do while maintaining hovering efficiency and low speed maneuverability. The lift offset coaxial rotor has been shown to have those capabilities.
openaire   +2 more sources