The present invention relates to a separator and more specifically, but not exclusively, to a centrifugal separator for the cleaning of a gaseous fluid. A centrifugal separator is provided as comprising a housing defining an inner space, and a rotor assembly for imparting a rotary motion onto a mixture of substances to be separated. The rotor assembly is located in said inner space and is rotatable about an axis relative to the housing. The rotor assembly comprises an inlet for receiving said mixture of substances, an outlet from which said substances are ejected from the rotor assembly during use, and a flow path for providing fluid communication between the inlet and outlet, wherein the outlet is positioned more radially outward from said axis than the inlet.