Turbine have a first and second rotor disc and a first and second cooling fluid conduit wherein the second cooling fluid conduit is extended through an annular axially extended bore having a radially outer extent defined by a radially innermost surface of the rotor discs

A core engine comprising an axis of rotation and configured to generate a flow of high energy combustion gases, said core engine comprising:

• a compressor, a combustor, and a turbine coupled in serial flow communication, said compressor coupled to said turbine by a shaft, said turbine comprising:
• a rotor comprising at least one disc, said at least one disc including opposing axially facing surfaces and a circumferentially extending radially facing surface extending between the axially facing surfaces;
• a plurality of blades positioned on said radially facing surface of said at least one disc;
• a first source of cooling fluid;
• a first cooling fluid conduit configured to channel a first flow of cooling fluid in serial flow from said first source of cooling fluid to a first forward axially facing surface, to a radially facing surface, and then to a first aft axially facing surface, and wherein the first cooling fluid is then configured to channel the first flow of cooling fluid to one or more of said plurality of blades positioned on said at least one disc;
• and
• a second cooling fluid conduit extended through an annular axially extended bore having a radially outer extent defined by a radially innermost surface of said first turbine rotor disc and second turbine rotor disc, wherein the second cooling fluid conduit is configured to channel a second flow of cooling fluid.