Computation of the Acoustic Field in an Annular Gas Turbine Combustion Chamber Using a Hybrid Approach

The acoustic field generated by flow unsteadiness in a model annular gas turbine (GT) combustion chamber is determined using a hybrid approach. In the flow solver the semi-compressible Navier-Stokes equations are resolved using LES as turbulence model. The acoustic solver is based on an inhomogeneous wave equation, where the instantaneous source terms are computed from the LES data in each time-instant. The flow and the acoustics in a GT combustor with co- and counter-rotating swirler burners have been considered. The results have shown that significant differences can be observed between the co- and counter-rotating configurations both in the flow and acoustic fields.