The implementation of advanced low-emission aircraft engine technologies and the
reduction of noise from airframe, fan, and jet exhaust have made noise contributions from an …

Combustion noise is becoming increasingly important as a major noise source in
aeroengines and ground based gas turbines. This is partially because advances in design …

This paper reviews both direct and indirect combustion noise. For convenience, they will
simply be referred to as combustion noise and entropy noise. Combustion noise has been …

This paper considers the effect of flow advection on entropy waves. The interest is in
whether entropy waves persist in gas turbine combustors, between the flame, where they …

The present paper deals with the generation of sound by the passage of acoustic or entropy
perturbations through a nozzle in the nonlinear regime and in the low-frequency limit. The …

The propagation of acoustic, entropy and vorticity waves through turbine stages is of
significant interest in the field of core noise. In particular, entropy spots have been shown to …

A method to predict combustion noise in real aero-engines using Large Eddy Simulations
(LES) of the combustion chamber coupled with an analytical approach to model the acoustic …

It is known that a uniform compressible flow supports three types of disturbances. One is
entropy wave. These waves are made up of temperature and density fluctuations only. The …

High performance aircraft operate at high jet temperature and velocity. Measured noise data
indicate that at afterburner condition their noise contain components not found in high …

A hybrid methodology combining a detailed Large Eddy Simulation of a combustion
chamber sector, an analytical propagation model of the extracted acoustic and entropy …