High-Fidelity Aeroelastic Analysis Of Rotor Blade Using Three-Dimensional Finite Element Formulation And Panel Method

Abstract

Three-dimensional (3D) solid finite element analysis (FEA) is developed to perform a high precision aeroelastic analysis of a rotor blade. This study is focus on geometrically nonlinear problems with linear elastic material properties. The 3D finite element (FE) formulation is based on updated Lagragian approach to estimate the large rotations and displacements. The 20-nodes solid element with eight Gaussian integration points is em-ployed to construct the FE model of rotor blade to prevent the element locking and hourglass modes. Moreover, the method to calculate the sectional loads of structure is presented based on force balance method. To do this, the internal force is adopted. For high-precision aeroelastic analysis, the 3D FEA is coupled with source-doublet panel method and vortex particle hybrid method using loosely coupling method to predict the aeroe-lastic behavior and blade sectional loads. The multi-purpose unmanned helicopter (MPUH) blade developed by Korea Aerospace Research Institute (KARI) is employed as a validation of the present analysis results. Herein, sectional load observation from experiments and aeroelastic analysis in hover flight condition using CAMRAD II are considered. Accuracy of the present high-precision analysis is evaluated by comparing pre-diction of performance, structural behaviors, and sectional load results.