Accession Number : ADA325524

Title :   Limit Cycle Oscillations (LCO) and Nonlinear Aeroelastic Wing Response.

Descriptive Note : Final rept. 1 Jun 93-31 May 96,

Corporate Author : DUKE UNIV DURHAM NC

Personal Author(s) : Dowell, Earl H.

PDF Url : ADA325524

Report Date : 04 DEC 1996

Pagination or Media Count : 13

Abstract : Limit cycle oscillations (LCO) have been observed for elastic wings at moderate to high angles of attack where separated flow is thought to occur. At transonic flow conditions with shock waves present, flow separation may occur at moderate angles of attack. For higher angles of attack, separation may occur at (low) subsonic conditions. Empirical quasi steady aerodynamic models based on steady state experimental data have shown some success in predicting the observed LCO. New theoretical aeroelastic models are proposed here to improve the prediction of LCO. Also proposed are simple, flow speed experiments to validate these theoretical models with an option for high speed experiments as well.

Descriptors :   *AEROELASTICITY, *OSCILLATION, *FLOW SEPARATION, *TRANSONIC FLOW, MATHEMATICAL MODELS, STEADY STATE, SHOCK WAVES, ANGLE OF ATTACK, NONLINEAR SYSTEMS, SUBSONIC CHARACTERISTICS, HIGH ANGLES.

Subject Categories : Aerodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE