Flutter analysis of propfans using a three-dimensional Euler solver

A three-dimensional aeroelastic solver is developed and applied to investigate the flutter of a propfan. The unsteady airloads are obtained by solving three-dimensional Euler equations. An implicit-explicit hybrid scheme is used to reduce computational time for the solution of Euler equations. A finite element model is used to obtain structural properties, and a deforming grid technique is used to simulate elastic deformations of the blade. The aeroelastic equations are formulated in normal mode form and are solved for flutter using both the time and frequency domain methods, The analysis is used to calculate the dynamic aeroelastic stability of a single rotation propfan model for which classical flutter was measured at subsonic relative flows. Comparisons with the experimental data and other calculated results are given.