Author: Elizabeth M. Lee-RauschPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 36
Book Description
Conical Euler Analysis and Active Roll Suppression for Unsteady Vortical Flows about Rolling Delta Wings
Author: Elizabeth M. Lee-RauschPublisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 36
Book Description
Conical Euler Analysis and Active Roll Suppression for Unsteady Vortical Flows about Rolling Delta Wings
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722125998
Category :
Languages : en
Pages : 30
Book Description
A conical Euler code was developed to study unsteady vortex-dominated flows about rolling, highly swept delta wings undergoing either forced motions or free-to-roll motions that include active roll suppression. The flow solver of the code involves a multistage, Runge-Kutta time-stepping scheme that uses a cell-centered, finite-volume, spatial discretization of the Euler equations on an unstructured grid of triangles. The code allows for the additional analysis of the free to-roll case by simultaneously integrating in time the rigid-body equation of motion with the governing flow equations. Results are presented for a delta wing with a 75 deg swept, sharp leading edge at a free-stream Mach number of 1.2 and at 10 deg, 20 deg, and 30 deg angle of attack alpha. At the lower angles of attack (10 and 20 deg), forced-harmonic analyses indicate that the rolling-moment coefficients provide a positive damping, which is verified by free-to-roll calculations. In contrast, at the higher angle of attack (30 deg), a forced-harmonic analysis indicates that the rolling-moment coefficient provides negative damping at the small roll amplitudes. A free-to-roll calculation for this case produces an initially divergent response, but as the amplitude of motion grows with time, the response transitions to a wing-rock type of limit cycle oscillation, which is characteristic of highly swept delta wings. This limit cycle oscillation may be actively suppressed through the use of a rate-feedback control law and antisymmetrically deflected leading-edge flaps. Descriptions of the conical Euler flow solver and the free-to roll analysis are included in this report. Results are presented that demonstrate how the systematic analysis of the forced response of the delta wing can be used to predict the stable, neutrally stable, and unstable free response of the delta wing. These results also give insight into the flow physics associated with unsteady vortical flows about delta wings undergoing forced m...
Conical Euler Simulation and Active Suppression of Delta Wing Rocking Motion
Author: Aeronautical Engineering
Author: Scientific and Technical Aerospace Reports
Author: 12th AIAA Applied Aerodynamics Conference
Author: Monthly Catalog of United States Government Publications
Author: Monthly Catalogue, United States Public Documents
Author: Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 808
Book Description
Author: 
Author: