This project is part of the joint project AG Turbo COOREFLEX-Turbo. DLR’s part of this project will be carried out by the Numerical Methods Department of the Institute of Propulsion Technology. The aim of these works is to extend the flow solver TRACE in such a way that the blade row interactions can be taken into account during flutter predictions.
Within the joint project this project is embedded into the project group “Expansion”. The final aim of this project is to gain, through fluid-structure simulations, a deeper understanding of the impact of unsteady blade row interactions on the self-excited and forced vibrations of turbine blades. The methods will be integrated in the linearized and nonlinear frequency domain solvers in TRACE which have to be generalized for harmonic blade deformations for structured and unstructured blocks. For flutter predictions the existing highly accurate nonreflecting boundary conditions have to be generalized for arbitrary mesh topologies. Furthermore the aeroelastic post processing methods of the frequency domain solver have to be generalized. All methods developed in this project will be validated against corresponding results obtained with the nonlinear unsteady solver.
Unsteady pressure distribution during the flutter analysis of a complex eigenmode of a low pressure turbine.