A centrifugal separator comprising - a frame, - a rotating part comprising a spindle and a centrifuge rotor enclosing a separation space, the rotating part being supported by the frame to rotate around an axis (x) of rotation, - a drive member configured to rotate the rotating part, - an inlet channel configured to provide fluid communication into the separation space and comprising a rotary channel part attached to the centrifuge rotor, a frame channel part attached to the frame, and inlet sealing means provided at the interface between the rotary channel part of the inlet channel and the frame channel part of the inlet channel, and - at least one outlet channel configured to provide fluid communication out from the separation space and comprising a rotary channel part attached to the centrifuge rotor, a frame channel part attached to the frame, and outlet sealing means provided at the interface between the rotary channel part of the outlet channel and the frame channel part of the outlet channel, wherein the inlet channel is configured to feed a product to be separated into the separation space and the outlet channel is configured to discharge a separated primary phase of the product from the separation space, and wherein the inlet channel and the outlet channel are arranged adjacent to and concentrically with each other, characterized in - that forcing means are provided to generate a leak flow through one of the inlet sealing means and the outlet sealing means in a first direction from the outlet channel to the inlet channel and thus to counteract, or prevent, leakage in the opposite direction from the inlet channel to the outlet channel. - a frame, - a rotating part comprising a spindle and a centrifuge rotor enclosing a separation space, the rotating part being supported by the frame to rotate around an axis (x) of rotation, - a drive member configured to rotate the rotating part, - an inlet channel configured to provide fluid communication into the separation space and comprising a rotary channel part attached to the centrifuge rotor, a frame channel part attached to the frame, and inlet sealing means provided at the interface between the rotary channel part of the inlet channel and the frame channel part of the inlet channel, and - at least one outlet channel configured to provide fluid communication out from the separation space and comprising a rotary channel part attached to the centrifuge rotor, a frame channel part attached to the frame, and outlet sealing means provided at the interface between the rotary channel part of the outlet channel and the frame channel part of the outlet channel, wherein the inlet channel is configured to feed a product to be separated into the separation space and the outlet channel is configured to discharge a separated primary phase of the product from the separation space, and wherein the inlet channel and the outlet channel are arranged adjacent to and concentrically with each other, characterized in - that forcing means are provided to generate a leak flow through one of the inlet sealing means and the outlet sealing means in a first direction from the outlet channel to the inlet channel and thus to counteract, or prevent, leakage in the opposite direction from the inlet channel to the outlet channel.