Prediction of Flutter of Turbine Blades in a Transonic Annular Cascade

Abstract

A parallel multiblock Navier-Stokes solver with the k‐ω turbulence model is used to solve the unsteady flow through an annular turbine cascade, the transonic Standard Test Case 4, Test 628. Computations are 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 Euler and Navier-Stokes computations due to three-dimensionality of the cascade model and the presence of a boundary layer separation, respectively.

Time-Domain Harmonic Balance Method for Turbomachinery Aeroelasticity

“…For external-flow aeroelasticity, the HB approach has been thoroughly validated [9,12,13,16], mostly for the AGARD test cases of Davis [35]. However, experimental data for turbomachinery aeroelasticity are more scarce; the standard aeroelastic configurations experiments of Fransson et al [28] are the reference in this respect and have been widely used to validate different numerical approaches [31,[36][37][38][39]. However, this is the first time these results are used to validate HB simulations.…”

Experimental Validation of Numerical Blade Flutter Prediction

“…In the open literature, only a few papers are devoted to the comparison of numerical and test data for 3-D blades [39][40][41][42]. All the authors of those papers compare calculated and measured aerodynamic damping (i.e., in fact, they validate aeroelastic codes based on the energy method).…”

Experimental and Numerical Study of Controlled Flutter Testing in a Linear Turbine Blade Cascade

“…Such methodologies are usually classified in time-linearized, harmonic balance and non-linear approaches both in frequency and time domain and require high quality experimental data for the validation and tuning, especially in off-design conditions. The stability results are evaluated by aerodynamic work which describes the exchange of energy between blade and flow [7,8].…”