About SPLEEN

The SPLEEN project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 820883.

SPLEEN investigates the aerodynamics of the next-generation high-speed Low Pressure Turbines. The project specifically focuses on the characterization of the secondary flow structures and the interaction of cavity purge and leakage flows with the mainstream. All these flows are of high technological interest and their accurate consideration is crucial for the development of compact high-speed turbines with high efficiencies.

SPLEEN main objectives

Develop knowledge and tools to design high-speed Low Pressure Turbines (LPT)
Fill shortage of aero measurements on LPT:
- - Engine-realistic conditions (Low Reynolds and high exit Mach numbers > 0.8, wakes, row interactions, leakages)
- - 3D flows
- - Interaction secondary-air and leakage flows
Measurements in cavities and main-stream
Tests multiple cavity-turbine configurations
Develop new technology to increase aero performance

Description of SPLEEN project

The SPLEEN project will mark a fundamental contribution to the progress of high-speed low-pressure turbines by delivering unique experimental databases, essential to characterize the time-resolved 3D turbine flow, and new critical knowledge to mature the design of 3D technological effects.

Context

There exists a critical shortage of detailed aerodynamic measurements in high-speed flows at engine representative conditions. This lack of knowledge becomes even more critical for the LP turbine operating at Mach numbers close or beyond the unity. A gap of relevant experimental data also concerns the impact of secondary flows on the turbine loss, and on the interaction of the secondary-air flows and leakage flows with the mainstream in a low-pressure environment.

SPLEEN research project aims:

To investigate secondary flow effects in a large-scale high-speed linear cascade at engine-representative Mach and Reynolds numbers by investigating different cavity-airfoil.
To propose, design and test an innovative technology concept that targets a reduction of the aerodynamic losses induced by the interaction of the secondary-air flow with the mainstream.
To heavily instrument and install a one-and-a-half turbine stage in a transonic rotating turbine rig. The turbine stage tests will allow characterizing the 3D unsteady flow field and the interactions between mainstream and cavity flows, in an engine-scaled environment under realistic flow conditions

Effects of secondary and leakage flows in high-speed LPTs

Experimental validation of geared-fan LP turbine technology
Effects of secondary and leakage flows on perfomance
Control strategy to reduce secondary flow losses

Outcomes and impacts

Experimental database high-speed LPT at engine-scaled conditions (up to TRL 5)
Unsteady flow measurements and aerodynamic performance of high-speed LP turbines
Characterization of interactions, between wakes, leakage flows and secondary flows
Evaluation of cavity shaping and flow control methods to reduce secondary flow losses