A decrease in the relative unevenness( Mf) of axial liquid velocity can improve the coalescence performance and separation efficiency in the gravity oil / water separator with coalescence component. A modified inlet component with round orifices was adopted,and the coalescence component with parallel plates was installed at 150 mm from the inlet. CFD simulation coupled with the Box-Benhnken design and response surface method was used to obtain the optimal combination of three main geometrical parameters for...