Abstract: Currently, the smoking effect is a technical direction that needs further optimization when users use the range hood in practice, and the design of a multi-flow field on the front end has an important impact on the smoke absorption effect of the entire machine. Computational fluid dynamics have far-reaching consequences on the research of the technical direction of range hood, used for the design and optimization of its fan system (scroll casing, impeller, motor), air ducts, and front-end flow channels. Range hoods are easily affected by crosswinds or other complex environments in existing kitchen environments, which can lead to a decrease in smoke absorption effectiveness, causing some smoke to escape into the kitchen and increasing the difficulty of cleaning the kitchen due to strong odors and smoke. Uses numerical simulation, comparative analysis, and experimental verification to design a special-shaped double air inlet that can expand the coverage of the negative pressure zone, reduce the negative pressure value directly above the pot smoke, improve the range hood's ability to capture smoke produced by the pot, and reduce smoke flow leakage. At the same time, due to changes in the flow of air at the front end, the noise level of the entire machine's semi-anechoic chamber is reduced by approximately 0.6 dB(A).

Key words: Multi-flow field on the front end, CFD, The smoking effect, Suction capacity