A centrifugal separator and a method of controlling a centrifugal separator are disclosed. The centrifugal separator includes a separator rotor delimiting a separation space. At least one tube extends from at least one radially outer portion of the separation space towards a central portion of the separator rotor. The method includes inter alia changing a rotational speed of the separator rotor from a first rotational speed to a second rotational speed, such that a heavy phase accumulation at a periphery of the separation space is displaced in a circumferential direction.