Aero Engines

Aerodynamics of Tandem Vanes

The project aims to examine the aerodynamics of tandem vanes in a compressor cascade with the particular interest of the 3D wall interaction.

Conventional blade designs achieve higher stage pressure ratios with an increased turning of the flow limited by the increased risk of separation. Therefore, modern compressor design engineering focuses on new blade designs to prevent separation while retaining the higher turning of the flow. Tandem blades are a novel approach to increase the stage pressure ratio by avoiding separation.
For tandem blades, the flow deflection is now realized by two blades positioned directly after one another. As a result the critical blade loading is split onto two blades allowing a higher pressure rise but also a more stabilized flow guidance thus reducing the risk of flow separation. The figures of the tandem blades visualize the reduced boundary layer development due to the shortened chord length and the optimized flow guidance.

The objective of the project is to develop validated computational approaches to support the early design phase of compressor modules with large deflection angles and to get detailed information about the influence of the secondary flow structures on the blade performance.

The objective of the project is to develop validated computational approaches to support the early design phase of compressor modules with large deflection angles and to get detailed information about the influence of the secondary flow structures on the blade performance.

This is supported by both experimental and numerical investigations. In the course of this project, four different configurations for 35° and 50° deflection angles and two different Lift Split (LS) variations are compared against conventional single CDA blades. In order to get a full understanding of the secondary flow development and in particular the influence of the stagnation point on the sidewall characteristics, both the axial and tangential pitch can be varied as well as the oncoming boundary layer thickness. With the use of tandem blades, the resulting losses can be reduced or avoided. Therefore the influence of the aerodynamic loading and the boundary layer thickness of the inflow on the blade performance are investigated.

Person of contact: Dipl.-Ing. Alexander Heinrich

The project is carried out in cooperation with the Research Association for Combustion Engines e.V. (Forschungsvereinigung Verbrennungskraftmaschinen e.V.), 2012/2016

Person of contact

References

2017

Tiedemann, C.; Heinrich, A.; Peitsch, D.
Increasing Blade Turning by Active Flow Control and Tandem Configurations: A Comparison
In ISABE, Editor
September 2017
Heinrich, A.; Tiedemann, C.; Peitsch, D.
Experimental Investigations of the Aerodynamics of Highly Loaded Tandem Vanes in a High-Speed Stator Cascade
In ASME, Editor, Volume Volume 2A: Turbomachinery from Turbo Expo: Power for Land, Sea, and Air
June 2017
ISBN
978-0-7918-5078-7

2016

Eckel, J.; Heinrich, A.; Janke, C.; Ortmanns, J.; Peitsch, D.
3D Numerical and Experimental Investigation of High Turning Compressor Tandem Cascades
In Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Editor
September 2016

2015

Heinrich, A.; Tiedemann, C.; Peitsch, D.
Experimental Investigations of Secondary Flow Development around Tandem Vanes in a 2D Linear Stator Compressor Cascade
In European Turbomachinery Society (Euroturbo), Editor
March 2015

2014

Heinrich, A.; Tiedemann, C.; Peitsch, D.
A New Linear High Speed Compressor Stator Cascade for Tandem Configurations
February 2014