In order to study the aerodynamic noise of a marine low-speed diesel turbocharger compressor

a hybrid calculation method of the computational fluid dynamics(CFD) and acoustic finite element method(FEM) was used to predict it

and verified by bench test. The unsteady flow field in the compressor was calculated under three different operating conditions

where the pressure fluctuation was used as a noise source in the acoustic simulation. Results indicate that the hybrid calculation method has a higher calculation accuracy and can be used for numerical prediction of the compressor's aerodynamic noise. Moreover

the main components of aerodynamic noise at the compressor inlet include discrete tonal noise and broadband noise. As observed

the discrete tonal noise exhibits an obvious acoustic directivity at blade passing frequency(BPF) and has two prominent peaks.