Abstract: An apparatus for separating particles from an airflow, the apparatus comprising a housing comprising an inner wall, and a body positioned within the housing and separated therefrom so as to define a substantially annular flow path between the body and the inner wall. The housing is rotationally stationary, and the body is rotatable relative to the housing about a rotational axis, the body comprising an impeller section having a first set of blades extending from the body into the annular flow path towards the inner wall of the housing, the impeller being rotatable for generating airflow through the apparatus and for generating swirl within the airflow, and a turbine section located downstream of the impeller section, the turbine section having a second set of blades for recapturing rotational energy from the airflow.

Abstract: A separator for removing dirt particles from an airflow, the separator comprising a first separation stage having an impeller, and a second separation stage having one or more cyclone bodies arranged in parallel, the first separation stage being upstream of the second separation stage. The impeller generates the airflow through the separator and concentrates the dirt particles within the airflow to produce a clean portion and a dirty portion of airflow, and wherein only the dirty portion of airflow is passed through the second separation stage.

Abstract: An apparatus for removing dirt from an airflow, the apparatus comprising an air inlet, an impeller for generating an airflow through the apparatus and for generating swirl within the airflow, the swirl throwing the dirt radially outwards and producing an outer dirty portion and an inner clean portion of airflow downstream of the impeller, and one or more splitters downstream of the impeller that bifurcate the airflow, separating the outer dirty portion from the inner clean portion.

Abstract: A separator for removing dirt particles from an airflow, the separator comprising a first separation stage having an impeller, and a second separation stage having one or more cyclone bodies arranged in parallel, the first separation stage being upstream of the second separation stage. The impeller generates the airflow through the separator and concentrates the dirt particles within the airflow to produce a clean portion and a dirty portion of airflow, and wherein only the dirty portion of airflow is passed through the second separation stage.

Abstract: An apparatus for separating particles from an airflow, the apparatus comprising a housing comprising an inner wall, and a body positioned within the housing and separated therefrom so as to define a substantially annular flow path between the body and the inner wall. The housing is rotationally stationary, and the body is rotatable relative to the housing about a rotational axis, the body comprising an impeller section having a first set of blades extending from the body into the annular flow path towards the inner wall of the housing, the impeller being rotatable for generating airflow through the apparatus and for generating swirl within the airflow, and a turbine section located downstream of the impeller section, the turbine section having a second set of blades for recapturing rotational energy from the airflow.

Abstract: An apparatus for removing dirt from an airflow, the apparatus comprising an air inlet, an impeller for generating an airflow through the apparatus and for generating swirl within the airflow, the swirl throwing the dirt radially outwards and producing an outer dirty portion and an inner clean portion of airflow downstream of the impeller, and one or more splitters downstream of the impeller that bifurcate the airflow, separating the outer dirty portion from the inner clean portion.