A numerical optimization was presented to reduce vibration and noise of a centrifugal fan volute. Minimum vibration was regarded as the aim of the optimization

and the sound field calculation for the structural vibration was performed with the final results of the optimization. Parametric modeling was done for the volute by the ANSYS software

and the optimum design of the volute was carried out using the volute local thickness as the design variable and the quadratic sum of the nodal velocity as the objective function. The numerical optimization results show that the present design method can reduce the volute vibration. Radiated noise of the volute before and after the optimization was calculated by the direct BEM

respectively. The results show that the radiated power of the volute vibration will decrease significantly after the optimization.