Расчетное исследование механизмов генерации тонального шума двухступенчатым вентилятором на режимах с дозвуковым течением

Abstract

Numerical investigation of the tone noise of a two-stage fan working at operational conditions with subsonic speed of flow is presented. Investigation was performed using a method of turbomachinery tone noise calculation in frequency domain. Modal spectra of the fan tone noise in the inlet and in the outlet were obtained as a result of the investigation. Power of the tone noise emitted by the fan is calculated. The analysis of the mechanisms of modes generation is performed. It is based not only on the results of the aforementioned calculation but also on the results of auxiliary calculation with specially constructed sets of modes, transmitted through the interfaces between blade rows. The analysis shows that the interaction of stator blades of the first stage and rotor blades of the second stage gives the main contribution to the tone noise of the fan both in the inlet and in the outlet of the fan.