EW-4 Junior Research Group Scale Resolved Aerodynamics of Turbomachinery Flows - Component and Airfoil

The focus of the junior research group Scale-resolved aerodynamics of turbomachinery flows - component and airfoil is to do detailed investigations on component level for fan, compressor and turbine, e.g. experimental investigations to further understand the boundary layer state or secondary flow formation of new and deteriorated parts and its effect on the performance of the component. Also numerical RANS simulations as well as scale resolved large eddy simulations are used to support the experimental findings. Apart from the improved understanding of the flow physics inside a gas turbine one main goal of the junior research group is the enhancement of numerical design tools for industrial applications.

Currently the junior research group is engaged in the improvement of the understanding the gap flow of variable stator vanes in a high-pressure compressor and the bleed air taken from the stage, as it appears in gas turbines for cooling the turbine and for supplying of the secondary air system with compressed air. The related project in cooperation with Rolls Royce Germany is engaged in the integration of new concepts to the removal of bleed air in gas turbines. CFD simulations for the assessment of the aerodynamics properties as well as the experimental investigation of different geometries in a wind tunnel and a low-speed-axial compressor (LSRC) are conducted. The main goal is to extend the understanding of the main formation of the gap flow of variable stators in combination with improved gap flow removal geometry on variable operating points and develop a better design process to improve the overall efficiency for design and part load.

Figure 1: Wake plane of a compressor cascade without (left) and with secondary air removal (middle) as well as test section of the LSRC with secondary air removal at the stator (right), (IFAS, Bode)

Another project alongside the interpretation of new parts is the operational wear of gas turbines and its components and parts. During operational use, an aircraft engine wears out. This reduces the performance of the engine and thus the efficiency. Periodic maintenance of the engine can partially reverse the closure. Maintenance tailored to the engine requires models that can predict the performance of an engine within an operating cycle, depending on the mission. Therefor an understanding of the essential mechanisms of action is necessary. The IFAS specifically investigates the fouling of the compressor. Fouling refers to the deposition of small (~ 2 - 10 µm) particles (eg smoke, oil or salt) from the ambient air on the compressor blades. The deposits increase the surface roughness of the blades and change their geometry. To investigate fouling, representative fouling topology blade geometries are created and studied both experimentally and numerically. For this purpose, stationary measurements are carried out on the cascade wind tunnel. The findings are then further investigated for transferability for transient flows at the LSRC. Finally, the results of individual stages are to be scaled to the entire compressor.

Figure 2: HPC-efficiency over time fort wo different jet engines (left) and surface topology due to wear (right), (IFAS, Bode)

Group Leader:
  • Dr.-Ing. Christoph Bode
PhD Students:
  • Dipl.-Ing. Melanie Achmus
  • Thorben Aufderheide M. Sc.
  • Dipl.-Ing. Nils Budziszewski
  • Daniel Kessler M. Sc.
  • Vera Tolksdorf M. Sc.
Academic Cooperation Partner
  • Institute of Turbomachinery and Fluid Dynamics (TFD), Leibniz Universität Hannover
Peer-review Journal:
  1. Budziszewski, N.; Friedrichs, J. Modelling of A Boundary Layer Ingesting Propulsor. Energies 2018, 11, 708. DOI: 10.3390/en11040708
  2. Kellersmann A, Weiler S, Bode C, Friedrichs J, Städing J, Ramm G. Surface Roughness Impact on Low-Pressure Turbine Performance Due to Operational Deterioration. ASME. J. Eng. Gas Turbines Power. 2018;140(6):062601-062601-7. DOI: 10.1115/1.4038246 (Vortrag und Paper bei der ASME Turbo Expo 2017 in Charlotte USA).
  3. Bode, C.; Friedrichs, J.; Frieling, D.; Herbst, F. (2017): Improved Turbulence Prediction in Turbomachinery Flows and The Effect on Three-Dimensional Boundary Layer Transition, International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ISROMAC 2017, 16-21 December, 2017, Maui, Hawaii DOI: 10.3390/ijtpp3030018
Peer-review Conference:
  1. Schwarzbach F.; Müller-Schindewolffs Ch.; Bode, Ch.; Herbst, F. (2018): Effect of the Turbulent Scales on Low-Pressure Turbine Cascade Aerodynamics Part B: Scale Resolving Simulations, Proceedings of the ASME Turbo Expo 2018, 11-15 June, 2018, Oslo, Norway, GT2018-75163
  2. Aufderheide, T.; Friedrichs, J.; Becker, B.: Effects of Secondary Air Removal on the Aerodynamic Behaviour of Compressor Cascade Flow. Proceedings of GPPS Forum 18 Global Power and Propulsion Society, 10.-12-Januar 2018, Zürich
  3. Aufderheide, T.; Stark, U.; Frantzheld, P.; Friedrichs, J.: Experimental and numerical investigations of a linear turbine cascade with sweep and dihedral. ISROMAC 2017 - 17th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Maui, USA, Dec 16-21, 2017

Head of Research Group Turbomachinery Aerodynamics & Performance
Head of Junior Research Group Scale resolved aerodynamics of turbomachinery flows - component and airfoil

Technische Universität Braunschweig
Institute of Jet Propulsion and Turbomachinery (IFAS)
Hermann-Blenk-Str. 37
D-38108 Braunschweig

phone: +49 531 - 391 94232
e-mail: chr.bode@ifas.tu-braunschweig.de

  last changed 12.11.2018
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