Prediction of flutter of turbine blades in a transonic annular cascade

A parallel multiblock Navier-Stokes solver with the k-omega turbulence model is used to solve the unsteady flow through on annular turbine cascade, the transonic Standard Test Case 4, Test 628. Computations arc performed on a two- and three-dimensional model of the blade row with either the Euler or the Navier-Stokes flow models. Results are compared to the experimental measurements. Comparisons of the unsteady surface pressure and the aerodynamic damping are made between. the three-dimensional, two-dimensional, inviscid, viscous simulations, and experimental data. Differences are found between the stability predictions by the two- and three-dimensional computations, and the Elder and Navier-Stokes computations due to three-dimensionality of the cascade model and the presence of a boundary layer separation, respectively.