transfer matrix, nozzle flow, acoustics, volumetric compressor
Pressure pulsations caused by a volumetric machines are still an important problem in the compressors, pumps and diesel engines manifolds and pipelines operation. Nowadays the problem is much more significant, for example, in the refrigeration industry where the variable revolution speed compressors are widely introduced. The classical Helmholtz resonators can attenuate the pulsations only in a narrow range of frequencies. One of the possibility to attenuate the pressure pulsations is to introduce the shaped nozzles into the compressor outflow and inflow pipelines. It Is a problem to introduce transfer matrix of the nozzle with variable geometry to the classical Helmholtz model to analyze the influence on the whole system. In the past, several identification methods were presented but some of them are useless for commercial use. Such a method must be reliable, easy and can’t be time-consuming. Two methods described in the literature meet all these conditions: the CFD-based identification method and analytical extension to the transfer matrix method. In this paper the identification of the generalized transfer matrix comparison for the nozzle-type geometry is presented. Such a comparison will allow to answer the question whether these methods are mutually exclusive, confirm or complement. This paper also present conclusions about the time-consuming and complexity of calculations.