Numerical Investigation on the Characteristics of Flow-Induced Noise in a Centrifugal Blower

Abstract

In the present study, a computational analysis of the flow in a centrifugal blower is carried out to predict a performance and to explain noise characteristics of the blower. Unsteady, 3D Navier-Stokes equations were solved with k-ε turbulence model using CFX software. CFD results were compared with the experimental data that is acquired from an experiment conducted with the same blower. The pressure fluctuation in the blower was transformed into the frequency domain by Fourier decomposition to find the relationship between flow behaviors and noise characteristics. Sound pressure level (SPL) which is obtained from wall pressure fluctuation at impeller outlet represents relative overall sound level of the blower well. Sound spectra show that there are some specific peak frequencies at each mass flow rate and it can be explained by flow pattern.

Flow-induced noise simulation using detached eddy simulation and the finite element acoustic analogy method

“…The far field sound pressure of low subsonic turbulent flow noise predicted by their hybrid method was in excellent agreement with experimental measurements. Zhang et al 3 proposed a hybrid method that combined LES with Lighthill's acoustic analogy to analyze the sound generated by turbulent flow passing through trash racks at the outlet of a pipeline, while Lee et al 4 computed the turbulent flow in a centrifugal blower and the resulting noise obtained from wall pressure fluctuations. Seo and colleagues 5,6 have proposed linearized perturbed compressible equations to compute low Mach number aeroacoustics.…”