Breather system for aircraft engine

An aircraft engine, comprising:

• a gaspath;
• a fluid-containing component;
• and
• a breather system, comprising:
• a main conduit extending from the fluid-containing component to an evacuation location, the main conduit including a venturi;
• a suction conduit extending from a seal for the fluid-containing component to a throat of the venturi;
• and
• a bypass conduit fluidly coupled to the main conduit at a bypass conduit inlet disposed upstream of the venturi and at a bypass conduit outlet disposed downstream of the venturi, a valve disposed in the bypass conduit, the valve having a closed configuration in which fluid flow through the bypass conduit is restricted and an open configuration in which fluid flow through the bypass conduit is allowed, the valve configured to move from the closed configuration to the open configuration when a pressure differential through the venturi is at a predetermined pressure differential, the predetermined pressure differential indicative of the venturi approaching or nearing a choked condition of the converging-diverging nozzle.

A method for operating a breather system in an aircraft engine, comprising:

• directing a flow of air from a fluid-containing component through a main conduit to an evacuation location via a converging-diverging nozzle disposed in the main conduit;
• using the flow of air through the converging-diverging nozzle to draw a leaking flow of fluid from a seal of the fluid-containing component or of an additional said fluid-containing component;
• and
• when a pressure differential through the converging-diverging nozzle reaches a predetermined pressure differential indicative of a choked state or of a near approaching choked state of the converging-diverging nozzle, opening a valve disposed in a bypass conduit, the bypass conduit providing a fluid flow path bypassing the converging-diverging nozzle.