Experimental Analysis on Performance of Air/Oil Centrifugal Breathers for Aircraft Engines Under Different Operating Conditions

This paper investigates the separation efficiency of modern aeroengine air/oil breathers, focusing on identifying configurations that enhance existing geometries. The study systematically varies parameters such as air flow rates and rotational speed, using well-known particle size distributions for testing different configuration. The experimental campaign involves various breathers with metallic grids of different geometries and mesh sizes, evaluating performance parameters such as pressure drops, oil consumption, and droplet cut-off size. The insertion of a metallic grid with a narrow mesh is found to offer a favorable trade-off in terms of pressure drops, oil consumption, and particle size at the separator exit. Results indicate that while increasing pressure drops of a reasonable amount, the selected geometries significantly reduce oil consumption and size of droplet at the exit of the breather.