Investigation of Tonal Noise in a High Pressure Turbine Stage Due to Temperature Inhomogeneous of the Inflow

Abstract

The tonal sound emission of a high pressure turbine stage due to total temperature inhomogeneous of the inflow investigated numerically. A non-uniform mean temperature made by a result of the discrete burners inside the annular combustion chamber. In present paper we made a setting that 14 periodic total temperature distribution in the azimuthal direction in the turbine inlet. Through comparison between non-uniform inlet temperature case and uniform inlet temperature case, the results show that the sound power emitted in the downstream direction is increased by 5.9 dB at the blade-passing frequency and by remarkably 11.6 dB at the first harmonic of the blade-passing frequency. This result indicated the total temperature fluctuation in the inlet of turbine stage would affect the sound field drastically.