Turbine engine advanced cooling system

A gas turbine engine defining a longitudinal axis, the gas turbine engine comprising:

• a compressor;
• a turbine;
• a combustor arranged axially between the compressor and the turbine and configured to drive the turbine with a stream of gas, the combustor comprising at least one liner defining a combustion chamber;
• a shield positioned axially between the compressor and the turbine, wherein the shield extends from a first plane positioned axially forward of the combustor to a second plane extending through an aft end of the combustion chamber, the first plane and the second plane each being perpendicular to the longitudinal axis;
• a combustor case;
• a drive shaft mechanically coupling the compressor to the turbine;
• a conduit configured to supply a cooling fluid to an annulus defined by the combustor case and the shield, the annulus configured to supply the cooling fluid to a first end of a gap between an outer surface of the drive shaft and the shield, the drive shaft and the shield configured to guide the cooling fluid from the first end of the gap to a second end of the gap, wherein the cooling fluid flows from the second end of the gap into an outlet of the compressor during operation of the gas turbine engine;
• a flow restrictor positioned in the gap and located between the first end of the gap and the second end of the gap, wherein the flow restrictor is a seal, wherein the seal is configured to limit fluid flow through the gap;
• and
• a radial pre-swirler configured to direct the cooling fluid from the annulus toward the drive shaft and into the gap, the radial pre-swirler configured to swirl the cooling fluid in a direction of rotation of the drive shaft, the radial pre-swirler positioned at an aft end of the shield and axially aft of the flow restrictor.