Development of a 2D equivalent model for predicting linear and nonlinear aeroelastic behavior of a cantilever NACA0012 wing

Abstract

Structural weight reduction is one of the main strategies explored nowadays to reduce manufacturing costs, impacting environmental costs. However, this structural weight reduction is often related to a reduction of material and may affect the structural mechanics of the system. Elasticity problems such as flutter can appear in lightweight structures. Therefore, this work presents a refined two-dimensional (2D) equivalent model for predicting the linear and nonlinear aeroelastic response of a cantilever wing based on a NACA0012 airfoil. The study aims to overcome the limitations of traditional 2D approaches, such as representing the wing by a single airfoil section at 75% span, which often leads to significant inaccuracies in flutter analysis. A 3D aeroelastic simulation framework is developed using Finite Element Method (FEM) analysis and unsteady Reynolds-averaged Navier-Stokes (URANS) computations. Based on the FEM results, a 2D model is developed, accounting for flexural and torsional dynamics considering the first vibration modes. Special attention is given to the elastic axis location, whose variation is shown to significantly influence the aeroelastic response. The 2D model is then validated against 3D simulations through parametric studies across a range of torsional stiffness values, capturing both flutter onset and limit-cycle oscillations. Results show that the proposed 2D model, when properly calibrated, replicates key 3D behaviors with significant reductions in computational cost, making it a reliable and efficient tool for preliminary aeroelastic assessments.