Abstract: In this study, the internal circulation air cleaner was applied in the kitchen and integrated with the exhaust hood. CFD numerical simulation was utilized to find a rational recirculation parameter under different air outlet velocity: 1~4 m/s and the air outlet angle: horizontal air outlet and upward 45° air outlet under 100 m³/h circulating purification flowrate. The best purifying effect was realized under 3 m/s air outlet velocity and upward 45° air outlet angle in the scope of discussion. It is found that compared with a separate range hood, the concentration of the breathing zone and the kitchen space can be reduced by 66.5% and 86.7% using this range hood with a recirculating purification unit. In the scope of the discussion of circulatory purification parameters, the concentration reduction rate of the breathing zone is in the range: 35.1%~66.5%; the concentration reduction rate in the kitchen space is in the range: 26.2%~86.7%. The purification experiments verifies that with the 3 m/s air apply velocity and 45° air outlet angle, the PM_2.5 and TVOC concentrations in the breathing zone sampling points could be reduced by 53% and 28%, respectively.

Key words: Range hood, Air cleaner, CFD, Kitchen