Session: 40-04: Turbine Cavity Flows and Flowpath Geometry Effects I

Paper Number: 154014

The First Application of a Miniature Laser Doppler Velocimetry System for Time-Resolved Velocity and Turbulence Measurements in a Two-Spool Rig 

This paper presents the first application of a two-dimensional miniature Laser Doppler Velocimetry system (mini-LDV) in a nonstationary, engine-representative flow environment. The miniaturized system enhances maneuverability, allowing it to be deployed in confined or difficult-to-reach areas where traditional turbomachinery-related LDV systems might not be suitable. Experiments were conducted at the Transonic Turbine Test Facility of the Institute of Thermal Turbomachinery and Machine Dynamics at Graz University of Technology.
The test setup consists of the high-pressure turbine stage, an intermediate turbine duct - in this case, a Turbine Vane Frame configuration (TVF), and the downstream located first low-pressure rotor. This allows for the replication of engine-relevant flow features. Additionally, the rotor-stator cavities of the setup were supplied with purge air. After validating the mini-LDV system on a separate test bench, the measurements for this work were performed in the TVF flow duct between the vane grid.
The results from the mini-LDV system were validated by comparing them with measurement data from a five-hole probe and constant temperature hot-wire anemometry, which showed good agreement.
Despite the mini-LDV's reduced laser power compared to traditional LDV systems used in turbomachinery, it effectively captured reliable flow data in the complex, unsteady environment of the two-spool rig.

Presenting Author: Francesco Mangini Graz University of Technology

Presenting Author Biography: Francesco Mangini was born in 1998 in Bari, Italy. He completed his bachelor's degree in mechanical engineering at Politecnico di Bari in 2020. He then moved to Graz for his master's degree and is currently a Ph.D. student at the Graz University of Technology, focusing primarily on unsteady flow and advanced measurement techniques.

Authors:

Andreas Koschu Graz University of Technology
Francesco Mangini Graz University of Technology
Asim Hafizovic Graz University of Technology
Nicolas Krajnc Graz University of Technology
Marios Patinios GE Aerospace
Pavel Svitek Measurement Science Enterprise, Inc.
Robert Krewinkel Graz University of Technology
Emil Göttlich Graz University of Technology