Abstract
Two mechanisms control combustion noise generation as shown by Marble and Candel (1977) [1]: direct noise, in which acoustic waves propagate through the turbine stages and indirect noise, in which vorticity and/or entropy waves generate noise as they are convected through turbine stages. A method to calculate combustion-generated noise has been implemented in a tool called CHORUS. The method uses the large eddy simulations of the combustion chamber obtained with the unstructured solver AVBP developed at CERFACS (Schonfeld and Rudgyard, 1999 [2]) and analytical models for the propagation through turbine stages. The propagation models (Cumpsty and Marble, 1977 [3]) use the compact row hypothesis to write matching conditions between the inlet and the outlet of a turbine stage. Using numerical simulations, the validity of the analytical methods is studied and the errors made quantified.