A Mid-Fidelity Aeroelastic Coupling Framework For Analyzing Flutter Dynamics In Rotorcraft Applications

Abstract

An aeroelastic coupling framework is presented, based on a time-resolved 3D surface-based coupling between a mid-fidelity aerodynamic solver (UPM) and a modal structural solver (HTModal). The aim is to improve the aeroelastic prediction quality with regard to dynamic phenomena, stability, and flutter in rotorcraft applications by enabling these phenomena to be accurately predicted in simulations, taking into account interaction effects. In this paper, the presented coupling framework is validated with different test cases. For this purpose, fixed-wing benchmark test cases presented in the literature (Goland, Pazy) are used to verify the prediction accuracy with regard to flutter speeds, as well as hover test data from the whirl tower test bench of the Institute for Rotorcraft and Vertical Flight at the Technical University of Munich to demonstrate the accuracy of the simulation, specifically in rotorcraft applications. The simulation results show good agreement with the test results, both in the static deformation analysis and in the dynamic stability and flutter analysis. Thus, the presented surface-based mid-fidelity coupling approach offers a promising approach for the analysis of arbitrary structures and shapes in rotorcraft applications.