Nonlinear Aeroelastic Analysis for A HALE Wing Including Effects of Gust and Flow Separation

作者：Zhicun Wang, P. C. Chen, Danny Liu, D. MOOK · 发表于：48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference · 年份：2007 · DOI：10.2514/6.2007-2106 · 被引用次数：19 · 研究领域：Aeroelasticity and Vibration Control、Computational Fluid Dynamics and Aerodynamics、Aerodynamics and Fluid Dynamics Research

[Abstract] Nonlinear aeroelastic analysis is essen tial for High Altitude Long Endurance (HALE) aircraft. In our previous work, a computational aeroelastic tool for Nonlinear Aerodynamics/Nonlinear Structure Interaction (NANSI) has been successfully developed. NANSI is a consistent nonlinear time-domain aeroelastic method that integrates and tightly couples a geometrically nonlinear intrinsic FEA/beam model with our generalized unsteady vortex lattice aerodynamic (UVLM) model including vortex roll-up and free wake. The previous NANSI results showed and correlated that aeroelastic instability (failure) indeed could occur for a HALE wing at high angle of attack and low altitude conditions. This paper describes our continuing efforts in enhancing NANSI to include the effects of discrete gust and/or flow separation at increasing angles of atta ck from the attached flow to the stall and post-stall ranges. Three enhanced NANSI models have been developed for a HALE wing: that with discrete gust, with stall flow and with the presenc e of both. Time-domain numerical studies were conducted for these three models under pre-cri tical and critical aeroelastic conditions. Critical HALE wing instabilities (notably the in-pl ane deflection) were found to take place invariantly at the same condition (~AoA =16 degree), but of different time scale to failure. Snapshots of flow simulations are also presented. T he NANSI time-domain solver is more effective than CFD solvers simply because it is a...