US Patent 10167734 Buffer airflow to bearing compartment

A seal support and duct assembly of a gas turbine engine includes a seal support housing disposed about a central axis, a duct housing attached to the seal support housing, the duct housing and the seal support housing defining the seal support and duct assembly, an outer annular cavity, an inlet that supplies the outer annular cavity with cooling buffer air, an inner annular cavity disposed radially inward of the outer annular cavity, a first plurality of outlets that provide the cooling buffer air from the outer annular cavity to the inner annular cavity, and a second plurality of outlets that provide the cooling buffer air from the inner annular cavity to an area surrounding a bearing compartment.