Enhanced Propagation of Aviation Noise in Complex Environments: A Hybrid Approach

Abstract

Accurate prediction of sound levels around airports and below flight paths can help faithfully represent the impact of aviation noise on communities. However, for large scale assessments, as are often performed by the U.S. Federal Aviation Administrationis environmental models, the accuracy of a model must be weighed against its efficiency. The hybrid propagation model (HPM) is capable of predicting propagation through complex environments. It is a composite of three methods-the generalized terrain parabolic equation (GTPE), fast field program (FFP), and straight ray models-each utilized in a different region of elevation angles from the source. If propagation conditions do not warrant use of the full model, one of the component models with faster runtime can be chosen as a surrogate. Analyses of cases using different source heights and including uneven terrain, refractive atmosphere, and ground type transitions, indicate when a detailed propagation model is needed, or when a simpler model is sufficient.

Numerical Investigation on Vortex‐Structure Interaction Generating Aerodynamic Noises for Rod‐Airfoil Models

“…In particular, the Lattice-Boltzmann-Method (LBM) has shown being a very promising technique for far field aeroacoustic prediction (Benjamin Duda, Ehab Fares, 2017), such as LAGOON landing-gear configuration [9] and Jet-plate interaction noise [10]. Currently the hybrid method is the most popular method which predicts the sound by combination of the computation fluid dynamics solvers for acoustic source identification [11][12][13] and the Lighthill's analogy theory for sound propagation [14]. The RANS/FW-H method was used to predict the aerodynamic noise of helicopter rotor successfully [6].…”