Entropy and fractal perspectives of a flapping wing subjected to gust

De, MM and Mathur, JS and Vengadesan, S (2021) Entropy and fractal perspectives of a flapping wing subjected to gust. Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 235 (15). pp. 2165-2181. ISSN 0954-4100

Full text not available from this repository.
Official URL: https://www.scopus.com/inward/record.uri?eid=2-s2....

Abstract

Studies on entomopter’s performance under the influence of gust have received impetus in the past decade. There exists a dire need to ascertain the threshold of the frontal gusty conditions which would destabilize these anthropogenic flyers. This would help to devise methods to mitigate the detrimental effects of gust. In light of this aspect, the present study aims at analyzing the onsets of instability in a flapping wing system subjected to temporal gust by employing recurrence period density entropy (RPDE) and detrended fluctuation analysis (DFA). Simulation of the flapping wing along inclined stroke is carried out for a Reynolds number of 150. This Reynolds number lies in the typical operating regime of fruit flies and entomopters like the Pico aerial vehicle. Numerical simulations are carried out to solve the laminar, unsteady, and incompressible Navier–Stokes equations. The dynamic meshing technique is employed to model flapping kinematics. Nine gusts with a combination of frequency and velocity ratios of 0.1, 0.5, and 1.0 are considered. Instantaneous horizontal and vertical forces are estimated. Time series of these forces are analyzed using RPDE and DFA paradigms. These analyses indicate that gust frequency of an order of magnitude higher than flapping frequency and gust amplitude of the order of magnitude as the wing’s root mean square velocity induces a possible onset of instability.

Item Type: Article
Uncontrolled Keywords: Average mutual information, Detrended fluctuation analysis, Entomopters, False nearest neighborhood, Gust, Recurrence period density entropy
Subjects: AERONAUTICS > Aerodynamics
ENGINEERING > Fluid Mechanics and Thermodynamics
ENGINEERING > Mechanical Engineering
Depositing User: Mrs. Usha Kumari
Date Deposited: 13 May 2022 10:59
Last Modified: 13 May 2022 10:59
URI: http://nal-ir.nal.res.in/id/eprint/13505

Actions (login required)

View Item View Item