Examination of the Acoustic Spectrum in the Generalized Acoustic Analogy for Heated Flows - Temperature Coupling Effects vs Direct Enthalpy Flux Generated Noise

The generalized acoustic analogy remains one of the most robust jet noise prediction models for jets of arbitrary cross section. In 2011, Afsar, Goldstein & Fagan (AGF)[1] formulated a jet noise model which reduced the acoustic spectrum formula to one involving 11 independent components of the spectrum of the turbulence auto- covariance tensor. In this paper we calculate this spectral tensor using a validated in-house LES code to obtain the unsteady flow. We assess the difference between heated and cold inflow conditions at fixed Ma = Uj/c∞.