A 2D-axisymmetric analytical model for the estimation of indirect combustion noise in nozzle flows

When designing new propulsion systems, it can be very useful to quickly determine thermoacoustic transfer functions of the elements downstream of the combustion chamber, since they may play a key role in the onset and development of combustion instabilities. In order to reduce computational times, semi-analytical methods use quasi-1D ow assumptions for the evaluation of nozzle transfer functions. A new 2D-axisymmetric model estimating indirect combustion noise generated by the acceleration of non-uniform temperature regions through a subcritical nozzle is presented. This model extends the 1D models proposed by Giauque et al. ("Analytical Analysis of Indirect Combustion Noise in Subcritical Nozzles," ASME J. Eng. Gas Turb. Power 134, pp 111202, 2012) and Duran & Moreau ("Solution of the quasi-one-dimensional linearized Euler equations using