Low-order modelling of the non-local acoustic reacting combustion chamber-dome interface in rocket engines

Alow-order model of the complex non-local reacting acoustic interface between the com- bustion chamber and the oxygen dome volume of typical rocket engine configurations is presented. Herein, computational effort is reduced by not resolving the complex face plate geometry comprising a potentially big number of injectors but by providing an adequate describing function of the interface in its entirety. The acoustic properties of the interface are described by so-called scattering matrices. The determination of the scattering matrix is performed in a separated procedure, which can be conducted analytically, numerically or by using experimental methods. Detailed evaluations of these lead to matrices that capture even small scale effects. For the usage of the scattering matrices in a time-domain solver digital filters are applied. This paper presents first results for the case of an orifice located in a straight pipe, which is considered as a simplified face plate configuration for longitudinal waves. The objective is to verify that the imposed scattering matrix can be reconstructed by using the two-source location method.