Vortex tube particle separators with coatings for rebound control

A vortex particle separator adapted for use with a gas turbine engine, the vortex particle separator comprising:

• a vortex tube arranged circumferentially around an axis and configured to receive atmospheric air laden with particles therein,
• a plurality of swirl vanes arranged within the vortex tube and configured to separate the atmospheric air into a first flow of air having the particles entrained in the first flow of air and a second flow of air that is relatively free of the particles,
• an outlet tube that extends into the vortex tube and cooperates with the vortex tube to define a scavenge passageway radially between the outlet tube and the vortex tube that receives the first flow of air, and the outlet tube defining an intake passageway that receives the second flow of air, and
• a layer of material on at least one of an interior surface of the vortex tube and a surface of the plurality of swirl vanes, the layer of material has a coefficient of restitution that is less than a coefficient of restitution of the at least one of the interior surface of the vortex tube and the surface of the plurality of swirl vanes to reduce a velocity of the particles that bounce off the at least one of the interior surface of the vortex tube and the surface of the plurality of swirl vanes to prevent the particles from bouncing into the intake passageway of the outlet tube,
• wherein the coefficient of restitution of the layer of material is 0.03 to 0.15.

A method of making a vortex particle separator, the method comprising:

• providing a vortex tube, a plurality of swirl vanes, and an outlet tube formed to define an intake passageway,
• applying a layer of material having a coefficient of restitution that is less than a coefficient of restitution of at least one of an interior surface of the vortex tube and a surface of the plurality of swirl vanes to reduce a velocity of the particles that bounce off at least one of the interior surface of the vortex tube and the surface of the plurality of swirl vanes to prevent the particles from bouncing into the intake passageway of the outlet tube,
• coupling the plurality of swirl vanes with the vortex tube such that the vortex tube extends circumferentially around the plurality of swirl vanes, and
• inserting the outlet tube into the vortex tube such that the outlet tube and the vortex tube cooperate to define a scavenge passageway radially therebetween,
• wherein an outlet of the scavenge passageway is fluidly coupled with a scavenge duct such that the scavenge duct directs the particles away from the scavenge passageway, the scavenge duct being annular,
• wherein the coefficient of restitution of the layer of material is 0.03 to 0.15.