Numerical analysis of the vibration and noise induced by the unsteady flow in a centrifugal compressor

Flow-induced vibration and noise widely exist in turbomachines and the connecting piping systems. The combined numerical method of computational fluid dynamics, computational structural dynamics, and computational vibroacoustics is employed to investigate the vibration and noise induced by the unsteady flow in the centrifugal compressor and pipes. Computational results indicate that the strongest pressure fluctuation is located on the clearance between the impeller and the stationary units due to the periodic rotor-stator interaction. However, the intense vibration occurs on the inlet and outlet pipes of the centrifugal compressor. Moreover, the computational result of the normal active acoustic intensity shows that the primary vibro-noise source is located on the outlet pipe. The computational result also clarifies that the thickness of the outlet pipe is one of the key parameters affecting the acoustic power output of the centrifugal compressor.