A novel grazing flow rig for acoustic liner investigations

Authors

Francesco Taddei - University of Florence
Maurizio De Lucia - University of Florence
Atabak Pourreza - University of Florence
Hamid Rashidi - University of Florence
Giacomo Pierucci - University of Florence
Matteo Messeri - University of Florence
Federico Fagioli - University of Florence
Michele Salvestroni - University of Florence
Davide Torzo - Avio Aero

Abstract

Acoustic liners can represent an effective strategy for noise reduction in aero engines. To assess the sound absorption effectiveness under representative operating conditions and to validate numerical methods, the treatments shall be characterized by using grazing flow rigs. Purpose of this survey is to describe the design solutions adopted in a brand-new test rig aimed at evaluating the performance of the liners under testing conditions representative of the turbine exhaust in an aircraft engine, i.e. high flow speed and temperature. The main components of the rig have been numerically investigated from an aerodynamic, thermo-structural and acoustic perspective. The relevant outcomes are reported in the paper. After the rig has been manufactured and assembled, a preliminary commissioning has been performed to verify the rig operability and performance, with special focus on the acoustic behavior.