Abstract

Determination of the acoustical properties for hot flow duct openings is a classical problem in acoustics. The importance of this issue usually becomes apparent when noise radiation from engine exhaust systems or burner chimneys is considered. In the paper a Finite Element Method (FEM) simulation has been applied to investigate the effects of high temperature media on the sound propagation through open duct termination. This paper is an extension for the recent experimental work performed by paper authors on acoustical properties of duct terminations exhausting hot gas. In order to simulate the experimental conditions, commercial FEM software COMSOL has been used. The acoustic pressure reflection coefficient of the duct termination is calculated from the complex pressure values simulated at the location of two microphones in the test-duct model. Two geometrically different simulated configurations for the jet, based on experimental observations, are studied. The numerical results obtained from simulations are compared to the experimental and theoretical ones and good agreement between the data is observed.