Jet noise reduction of spherical tuyeres with serrated trailing edges

Abstract

The geometry of a jet nozzle has a direct effect on the noise of spherical tuyeres. The addition of a serrated structure to the trailing edge of a spherical tuyere is proposed to reduce the jet noise. A full-scale test bed is built to verify the jet velocity distribution of the spherical tuyere, and the tuyere jet noise prediction is verified through analogy experiments. The large eddy simulation (LES) model and Ffowcs Williams–Hawkings (FW–H) equation are used to predict the jet flow field and jet noise, respectively. The results show that the serrated trailing edge reduces the velocity attenuation and turbulent kinetic energy (TKE) on the downstream axis of the jet, and the radiated noise is significantly reduced at 10–60 Hz. However, when the serration width is excessively large, the serration increases the radiated sound pressure level (SPL) of the tuyere. In addition, optimal serration parameters can be used to reduce the effect of tuyere radiation noise on the standing and sitting postures of residents. The maximum radiated overall SPL can be reduced by 3.78 dB at the sitting height. The simulation data and analysis results can provide reference for the low-noise optimization design of spherical tuyeres.