US Patent 11905841 Buffer air method and system for a bearing compartment

A method of operation is provided during which buffer air flows into a buffer cavity in a turbine engine. The buffer cavity surrounds a bearing compartment in the turbine engine. Leakage air flows across a buffer seal device in the turbine engine. The buffer air and the leakage air are combined to provide combined air. The combined air is vented to a pressure sink such that: a pressure of the buffer air within the buffer cavity is maintained at or below a maximum buffer air threshold during operation of the turbine engine; and a flowrate of the leakage air across the buffer seal device is maintained at or above a minimum leakage air threshold during the operation of the turbine engine.