M. Tamayama

For the transonic flow fields around a thin airfoil, the aerodynamic nonlinearity against an aileron deflection is arisen by the existence of shock waves on the aileron. In the past study, the characteristics regarding this nonlinearity have already reported. But, in the first place, the comparison between the steady and unsteady flow behaviors with varying an aileron deflection has not been conducted yet. This comparison was carried out at first in this study. From this consideration, it becomes obvious that conducting accurate simulations seems crucial to predict the nonlinearity. To realize this prediction with a time-efficient and accurate manner, the Reduced Order Modeling, ROM, method with the Proper Orthogonal Decomposition, POD, method was attempted. From the considerations on the eigenfunctions acquired in the POD process, two POD modes can reproduce the original flow properties with a moderate accuracy; although it is needed with more modes in order to conduct better approximation. The attempt of ROM method is at the preliminary stage; and, the ODE equations to be time-integrated in ROM method were simply derived from the original full-order simulated results by applying the least square fitting. The results of this ROM simulation show an ability to approximate the flow fields as far as the integral time period is moderate. At the same time, the limit of the ROM technique used in this study also came out.

International Forum on Aeroelasticity and Structural Dynamics, 2005, München

Conference Paper

englisch

21,0 x 29,7 cm, 13 Seiten

DGLR-Bericht, 2005, 2005-04, International Forum on Aeroelasticity and Structural Dynamics 2005; S.1-13; 2005; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

in getr. Zählung;

transonic flows, nonlinearity, unsteady aerodynamics, reduced order modeling

Bibliothek

2005