Noise Testing Of Range Hood And Numerical Simulation Of The Inner Flow Field In Its Fan

With the improvement of people’s living standards, in Chinese urban householdsthe range hood which is increasing penetration, become an essential appliance inpeople’s lives.In this paper, A certain type of range hood noise is tested and thecomputational fluid dynamics (CFD) method is adopted to analyze fan system.This paper first discusses the multi-wing centrifugal fan noise generationmechanism and the characteristics, as well as the spectrum analysis theory. In order tofind the vibration and noise sources of a certain type of range hood, vibration andradiated noise produced by a working range hood is measured with vibrationaccelerometers, microphones and other precision instruments under the condition ofsemi-free sound field, according to the national standards. Spectrum analysis methodsare adopted to analyze the spectral characteristics of the noises, and the frequencydistribution is obtained. The vibration and noise sources of the range hood are finallyfound. Some instructive conclusions will be helpful to study the aero-acousticperformance of range hood.The flow field of range hood fan is numerical simulated by CFD software Fluent,the three-dimensional time averaged N-S equation, the RNG k turbulent model andstandard wall functions are used, Finite Volume Method,the SIMPLEC algorithm areselected. Through the Fluent and Tecplot post-processing, the range hood fan internalflow characteristics are analyzed. Based on the study of the flow efficieney in differentwheel diameter ratio of impeller, their influence is found out.it is useful for the optimaldesign of range hood.