Session: 34-05 Harmonic balance methods

Paper Number: 127237

127237 - On the Development of an Efficient Sliding Mesh Interface for the Harmonic Balance Method, Part II: Effects of Casing Treatments on the Aerodynamic Damping of a Compressor Blade 

In recent years the Harmonic Balance method has become a popular tool in the field of turbomachinery design.
While it can efficiently capture nonlinear effects in time-periodic main flows, its application to complex configurations such as cavities or casing treatments requires sophisticated domain coupling methods.
To address this topic we present an algorithm for the coupling of non-conforming mesh topologies across domain boundaries in a series of two papers.

In this second paper, we demonstrate that the novel sliding mesh method presented in the first part for the first time enables efficient flutter analysis of compressor rotors including casing treatments.  
To this end, a specific mesh topology for the frequency domain approach to connect stationary cavities with the moving rotor domain is presented by means of a transonic compressor rotor. 
It is shown that the presented mesh topology has no significant impact on the flow characteristics of interest and can therefore be applied to the flutter analysis with Harmonic Balance.
HB results of the flow solver TRACE are successfully verified by expensive time domain simulations with respect to average flow quantities as well as the relevant frequency spectrum.The influence of casing treatments on the aerodynamic damping of the rotor is shown and evaluated on the basis of comparative calculations without casing treatments.

Presenting Author: Maximilian Hartmann MTU Aero Engines AG

Presenting Author Biography: Master of Science at Ruhr-University Bochum in mechanical engineering in 2021.
PhD candidate at MTU since 2022.

Authors:

Maximilian Hartmann MTU Aero Engines AG
Daniel Schlüß MTU Aero Engines AG
Georg Geiser German Aerospace Center (DLR)
Felix Schwarzenthal German Aerospace Center (DLR)
Graham Ashcroft German Aerospace Center (DLR)
Florian Herbst MTU Aero Engines AG