New modular fan rig for advanced aeroacoustic tests - Acoustic characterization of the facility

Abstract

This paper presents the acoustic qualification of the new ECL-B3 test-rig at École Centrale de Lyon in France. This new experimental facility is part of the PHARE project, which is supported by the French National Research Agency through the EquipEx program. The testrig was designed and manufactured together by Safran Aircraft Engines and École Centrale de Lyon for aeroacoustic tests of a reduced-scale fan stage, and can support a wide range of R&D studies using state-of-the-art equipment and instrumentation, such as turbulence control screen, pole rakes, hot-wires, particle image velocimetry, pressure transducers, and internal and external microphone arrays, among others. These will allow for a better understanding of aeroacoustic phenomena in future fan stages, such as the influence of inflow distortion, aerodynamic instabilities due to rotating stall and surge, and noise generation and propagation. Furthermore, the high-speed acquisition system that has been set up in the test facility is suitable for highly instrumented aeroacoustic measurements. For instance, up to 192 microphones can be installed simultaneously. Commissioning tests have been performed using a 20" fan stage designed and manufactured by Safran Aircraft Engines. Preliminary results indicate that this facility can provide state-of-the-art aeroacoustic measurements (low inlet distorsion, low background noise levels, ...), and can be useful for advanced aeroacoustic tests of modular fan stages. Thus, the ECL-B3 facility is suitable for the maturation of noise reduction technologies up to technology readiness level of the order of 3 to 4.

Influence of a Turbulence Control Screen on the Aerodynamic and Aeroelastic Behavior of a UHBR Fan

“…In order to make results of both configurations comparable to each other and provide information for design of experiments (DoE) procedures for future measurement campaigns, it is necessary to study the influence of the TCS in detail. Salze et al [27] already analyzed acoustic spectra from measurements with and without TCS. These measurements have been carried out within the project ENOVAL at the test facility ECL-B3 (see also [28]) and allowed the validation of TCS for acoustic experiments.…”

The Advection Boundary Law in presence of mean-flow and spinning modes

“…In Section 1.1, we present the scattering simulations on a cylindrical waveguide excited by spinning modes. Then, in Section 2, we present the attenuation of the azimuthal modes achieved on the Phare2 test-bench, 7,8 confirming the potentiality of such innovative liner.…”

“…We present here the simulation results obtained by such control law which has been also tested experimentally on the test-bench Phare2. 7,8 It is hence helpful for the interpretation and appreciation of the experimental results as well.…”

Electro-active acoustic liner for the reduction of turbofan noise

“…The air flow, up to about 40 kg.s −1 , generated by the turbofan, passes through acoustic baffles on the roof of the building. Using this test-rig, interest was focused on the characterization of UHBR industrial turbofans, regarding acoustic aspects [9], modal decomposition [6], and aerodynamic instabilities [3]. Current and future test campaigns are dedicated to the realization of an academic open test-case [2,5,8].…”