Log in

Login to your account

Username *
Password *
Remember Me
: 3 + 9 =

GPPS Journal Papers

Purge flow effects on rotor hub endwall heat transfer with extended endwall contouring into the disk cavity

Star InactiveStar InactiveStar InactiveStar InactiveStar Inactive
Dominic D. Hänni 1, Rainer Schädler 1, Reza S. Abhari 1, Anestis I. Kalfas 2, Gregor Schmid 3, Ewald Lutum 4, Nicolas Lecoq 4

1 ETH Zurich, Sonneggstrasse 3, ML J 33, Zürich8092, Switzerland
2 Aristotle University of Thessaloniki, Thessaloniki54124, Greece
3 Siemens AG, Mellinghofer Str. 55, Muelheim an der Ruhr45473, Germany
4 MTU Aero Engines AG, Dachauer Str. 665, München80995, Germany


Efficiency improvements for gas turbines are strongly coupled with increasing turbine inlet temperatures. This imposes new challenges for designers for efficient and adequate cooling of turbine components. Modern gas turbines inject bleed air from the compressor into the stator/rotor rim seal cavity to prevent hot gas ingestion from the main flow, while cooling the rotor disk. The purge flow interacts with the main flow field and static pressure field imposed by the turbine blades. This complex interaction causes non-uniform and jet-like penetration of the purge flow into the main flow field, hence affecting the endwall heat transfer on the rotor. To improve the understanding of purge flow effects on rotor hub endwall heat transfer, an unshrouded, high-pressure representative turbine design with 3D blading and extended endwall contouring of the rotor into the cavity seal was tested. The measurements were conducted in the 1.5-stage axial turbine facility LISA at ETH Zurich, where a state-of-the-art measurement setup with a high-speed infrared camera and thermally managed rotor insert was used to perform high-resolution heat transfer measurements on the rotor. Three different purge flow rates were investigated with regard to hub endwall heat transfer. Additionally, steady-state computational fluid dynamics simulations were performed to complement the experiments. It was found that the local heat transfer rate changes up to ±20% depending on the purge flow rate. The main part of the purged air is ejected at the endwall trough location and swept towards the rotor suction side, which is caused by the interaction of main flow and the cavity extended endwall design. The presence of low momentum purge flow locally reduces the heat transfer rate. Changes in adiabatic wall temperature and heat transfer (depending on purge rate) are observed from the platform start up to the cross passage migration of the secondary flow structures.

Read Full Paper (Visit Journal Website)

Global Power and Propulsion Society (GPPS)


Address :

Landis + Gyr-Strasse 1, 6300 Zug, Switzerland

Tel. :

+41 44 632 50 72

Recent tweets

To minimize the potential impact of technical difficulties associated with a registration "bottleneck" occurring ju… https://t.co/z3cqVSd6nV
Vote today for your GPPS 2020 Awards candidate. Our new online form is now available. https://t.co/9axXsiXfwt
Register your place at the first GPPS Chania20 Online Conference. We look forward to hearing the latest leading-edg… https://t.co/gQLlKqkJ9E