INVESTIGATION OF JET NOISE CHARACTERISTICS FROM A GAS TURBINE NOZZLE USING AN INTEGRATED CFD - CAA APPROACH CONSIDERING FLOW VELOCITY EFFECTS

Tóm tắt

This article presents an integrated Computational Fluid Dynamics - Computational Aeroacoustics (CFD-CAA) approach for investigating jet noise characteristics generated by a gas turbine engine nozzle under subsonic conditions. The aerodynamic field is simulated using the Unsteady Reynolds-Averaged Navier-Stokes (URANS) method with the k – ω SST turbulence model to obtain the unsteady velocity field, combined with the Broadband Noise Model in Ansys Fluent to predict the Acoustic Power Level (APL). The research object is the NASA acoustic reference nozzle (ARN2). The model was validated through comparison of the velocity field with published PIV data. After validation, parametric studies are conducted to assess the influence of the freestream Mach number and jet Mach number on the acoustic power level. Results indicate that APL increases marginally with the freestream Mach number (approximately 2.2%), but increases significantly with the jet Mach number (a 10.3% increase when Mjet increases from 0.513 to 0.75). The URANS-Broadband approach demonstrates acceptable reliability in analyzing noise variation trends while significantly reducing computational costs compared to several other methods.