NASA’s Glenn Research Center has developed a suite of software tools to predict aircraft engine noise, supporting the design of quieter propulsion systems. These tools include JeNo, MGBK, V072, TFaNS, Linflux, BFANS, RSI, WOBBLE, and MPT, each tailored for specific aspects of noise prediction and analysis.
JeNo, a key tool in the suite, predicts jet noise using Lilley’s Acoustic Analogy and mean flow solutions from Reynolds-Averaged Navier-Stokes (RANS) codes. It calculates far-field sound spectral density for axisymmetric jets and has been validated for subsonic and low supersonic, unheated jets.
MGBK, developed before JeNo, is used to predict noise trends in complex engine exhaust nozzles, particularly for assessing the noise reduction benefits of chevrons—serrations on turbofan nozzles. V072, another tool, provides quick noise estimates for early design stages, focusing on rotor/stator interaction tone noise.
TFaNS extends the capabilities of V072 by accounting for blade row acoustic coupling effects and propagating tones to the far field. Linflux, while more computationally intensive, offers detailed 3-D flow and blade geometry analysis, validated against experimental data.
BFANS calculates broadband noise from turbulence impinging on rotor blades and stator vanes, combining with experimental data to identify noisiest components in fan stages. RSI predicts broadband noise from rotor wake turbulence interacting with exit guide vanes, with mode-by-mode spectral analysis.
WOBBLE models propeller noise influenced by unsteady blade loading, accounting for inflow angles and acoustic effects. MPT estimates multiple pure tone noise from supersonic fan blade tip speeds, incorporating CFD flow predictions for real-world effects like manufacturing variations.
ADPAC, developed by the Allison Engine Company under NASA contracts, solves internal/external flow problems for future-concept short-duct turbofan engines, offering flexibility in modeling 2D, axisymmetric, and 3D flows with various boundary conditions.