Application of Transfer Matrix Method in Acoustics

This paper shows the application of the Transfer Matrix Method in the Acoustics Module of COMSOL Multiphysics. The analyzed system is the combustion chamber of an industrial gas turbine and in the 3D acoustic simulation the burners are geometrically cutand substituted by transfer matrices. The application of this methodology allows us to take into account parameters which can not be considered in the Acoustics module (e.g. meanow and viscosity) and to reduce the computational effort. The Transfer Matrix method is used when the whole system can be represented into a sequence of subsystems that interact only with adjacent subsystems. This method is frequently used in mathematics and, particularly, in acoustics. The application of the present method is really useful, because it permits to break the total system into a network of subsystems, linked together by transfer matrices. These matrices can be obtained analytically, experimentally or numerically. The great importance of this method is the possibility of using data from experiments or from detailed numerical simulations inside the transfer matrix.