Our aim in the present study is to increase grease separation by optimising the discharge performance of cooking oil fumes. A novel range hood with an outer cylinder and guide vanes of exhaust (GVE) is proposed. The geometric configuration of the hood is optimized by a reverse design method developed by coupling back propagation neural networks, mind evolutionary algorithms, and computational fluid mechanics. The primary objective of the range hood is to maximise the exhaust airflow rate with good grease separation. At the optimised conditions, the inlet and outlet blade angles are 80 degrees and 176 degrees, respectively, while the heights of the blade and guide vane are 0.180 and 0.245 m, respectively. The optimal number of blades and guide vanes are 29 and 7, respectively, while the optimal diffuser diameter is 0.340 m. The proposed range hood exhibits excellent performance of grease particle separation compared to multi-blade centrifugal fans with volutes. In addition, the outer cylinder and GVE of the range hood exhibit a large separation efficiency for particles in the size range of 1-4 mu m, while impeller blades mainly separate grease particles in the size range of 4-10 mu m. (C) 2019 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.