On Problems Associated with Modeling Wing-Tail Configurations from Wind Tunnel Data

Abstract

This paper considers factors that contribute to poor identification of unsteady aerodynamics from wind tunnel data for an airliner configuration. One approach to modeling a wing-tail configuration is considered and applied to both steady and largeamplitude forced pitch oscillation wind tunnel data taken over a wide range of angles of attack but a limited range of amplitude and frequencies. The identified models fit the measured data well but in some cases with inaccurate parameters. Only limited conclusions can be drawn from analysis of the current data set until further experiments can be performed to resolve the identification issues. The analysis of measured and simulated data provides some insights and guidance on how an effective experiment may be designed for wing-tail configurations with nonlinear unsteady aerodynamics. Nomenclature

Nonlinear Unsteady Aerodynamic Modeling Using Wind-Tunnel and Computational Data

“…Ref. [29] included discussions on issues with identifiability and important considerations for experiment design using single-frequency forced oscillation data.…”