Directed cooling for rotating machinery

A rotating machine comprising:

• a hub portion, wherein the hub portion comprises an outer circumference, an inner circumference, and a face;
• a ring portion, wherein the ring portion comprises an inner circumference that is metallurgically bonded to the outer circumference of the hub portion along a circumferential bond line;
• and
• a cooling channel formed on the face and configured to direct cooling air to the bond line, wherein the cooling channel extends from a radially inner location along the face to a radially outer location along the face, and wherein the cooling channel is configured as a recess formed into an outer surface of the face,
• wherein the ring portion further comprises an end, wherein the end comprises a circumferential flange extending outward from the end and positioned radially above the bond line, wherein the face of the hub portion includes a circumferential recess radially below the bond line, wherein the flange and the recess define a circumferential bond line channel along both the end and the face that distributes cooling air circumferentially along the bond line, wherein the radially outer location along the face is positioned radially below the circumferential bond line channel, and wherein, at the radially outer location along the face, the cooling channel joins fluidly with the bond line channel such that the cooling air is able to flow from the cooling channel into the bond line channel.