For the 1D3D,2D2D and 1D2D cyclone designs,the predictions of pressure drop are 1071 Pa (4.3 inch ),854 Pa (3.43 inch) and 390Pa (1.57 inch) respectively at their own design inlet velocity (16 m/s/3200 fpm,15 m/s3000 fpm and 12 m/s/2400 fpm,respectivety)