Project is sponsored by the Austrian Research Agency FFG
Project Start: 2013; Project End: 2016
HELDECO CAD/CAM Fertigungstechnik GmbH
Project Coordinator: Institute for Thermal Turbomachinery and Machine Dynamics
Project Applicants / Contact:
Dip.-Ing. Dr.techn. Andreas Marn (Project Manager),
Dipl.-Ing. Florian Schönleitner
The demand of more silent and cleaner aero engines leads to new innovative engine concepts.
In these concepts (e.g. open rotor) the rear engine bearing moves forward beneath the struts
of the mid turbine frame. The struts of the turbine exit casing (TEC) need not to carry the
engine mount any longer, hence the struts can be designed aerodynamically and acoustically
optimised, which reduces the sound pressure level. The support function is now taken by the
struts of the mid turbine frame, but these struts have to be thick and rigid, raising weight
of the engine. Therefore, these concept removes the usually following vane row and integrates
turning into the struts resulting in a turning mid turbine frame. Due to these changes the
aerodynamically excitation of the adjacent low pressure turbine stages has changed and up to
now numerical tools are not capable to reliable predict the fluid-structure-interaction. One
important step towards these new engine architectures is to examine the influence of the changed
components onto the forced response of the blading. Therefore, experimental investigations will
be conducted at the Institute for Thermal Turbomachinery and Machine Dynamics using both, the low
pressure turbine test rig and the two-spool rig. As first step, the influence of the TEC blading is
investigated followed (second step) by the test concerning the turning mid turbine frame. In order
to be able to separate the influence of the upstream blade rows from the overall influence (upstream
and downstream blade rows) the first test is a strutless TEC. Then the influence of different TEC
configurations is investigated. After that the effect of the turbine mid turbine frame struts is examined.
As result the influence of the struts is examined and a data base is created which enables to calibrate
numerical tool to improve the prediction quality.
1. Improved understanding of the flow physics and excitation mechanisms of the low pressure turbine
2. Turbine exit casing (TEC)-Low Pressure Turbine (LPT) Interaction
3. Database for aeroelastic code calibration
4. Establishment of design rules and a validation database
Schönleitner, F., Traussnig, L., Heitmeir, F., Marn, A., 2015, " Modal Characteristics, Strain Gage Setup and 1-way FSI of a Low Pressure Turbine Rotor as Preparation for Upcoming Ex-perimental Aeroelastic Investigations," ASME Paper GT2015-42717.
Schönleitner, F., Traussnig, L, Marn, A., Heitmeir, F., 2015, "Detection of Mistuning due to Manufacturing Tolerances and Blading of a Low Pressure Turbine Rotor with Hammer Head Design of the Blade Root," 11th International Conference Vibrations in Rotating Machines.
Justl, M., Traussnig, L., Schönleitner, F., Marn, A., Heitmeir, F., 2014, "Numerical Investiga-tions Regarding Contact Modelling for Evaluating the Modal Characteristics of a Low Pressure Turbine Rotor Blading," ASME Turbo Expo, Düsseldorf, Germany.
Traussnig, L., 2015, "Charakterisierung der modalen Eigenschaften einer Niederdruckturbinenbeschaufelung," Diploma Thesis
Justl, M., 2015, "Numerische Charakterisierung sowie aeroelastische Untersuchung einer Niederdruckturbinenbeschaufelung," Diploma Thesis