A centrifugal separator for separating non-gaseous particles from a gas flow having a separator housing enclosing a rotor with a raw gas inlet, a clean gas outlet, and a particle outlet. A circumferential wall encloses the rotor. A raw gas flow is guided axially into the rotor. A clean gas flow is guided out of the rotor and then between the rotor and the circumferential wall to the clean gas outlet. The rotor comprises particle separation elements so that particles separated from the gas flow are centrifuged onto the circumferential wall. The circumferential wall particles are guided to the particle outlet via at least one particle guide trough running diagonal to the rotor axial direction on the interior of the circumferential wall. A radius of each trough as well as the distance between the rotor and the circumferential wall decreases in the direction of the clean gas flow.