Abstract: A particle separator which is highly efficient in the removal of suspended particulate matter from a gaseous fluid flow; which depends for its operation on centrifugal forces acting on the particulate matter which are caused and controlled by rotational direction changes induced in the fluid flow by the shape of the inner walls of the chamber which comprises the particle separator; and which derives its efficiency not only from controlability of the turning radius of the fluid flow during an induced rotational direction change, but also from recognition and utilization of the fact that particles suspended in that portion of the fluid flow which is nearest the center of rotation of the fluid flow may be unable to cross the center of fluid flow (which has a higher velocity than the outer edges of the flow) and thus be unable to separate from the flow during induced rotational direction changes necessitating a second induced rotational direction change wherein those particles which were formerly nearest the cent