Patent ID: 7131813

Claim:
A turbine shaft in a turbine engine, comprising: a first cooling circuit characterized by a first region separated flow wise from a third region by a second region, said first cooling circuit being further characterized by a fourth region, a fifth region and a sixth region connected flow wise to one another to pass fresh air but separated flow wise from the first, second, and third regions; wherein the first region contains live steam during operation, wherein the third region contains used steam during operation, wherein the second region is located within a first bade, wherein the fourth region is located within a first guide vane to pass fresh air therethrough to the fifth region, wherein the fifth region passes fresh air received from the fourth region to the sixth region, and wherein the sixth region is located within the first blade and passes therethrough fresh air received from the fifth region; and a second cooling circuit characterized by a first region separated flaw wise from a third region by a second region, said second cooling circuit being further characterized by a fourth region, a fifth region and a sixth region connected flow wise to one another to pass fresh air but separated flow wise from the first, second, and third regions; wherein the first region contains live steam during operation, wherein the third region contains used steam during operation, and wherein the second region is located within a second blade, wherein the fourth region is located within a second guide vane to pass fresh air therethrough to the fifth region, wherein the fifth region passes fresh air received from the fourth region to the sixth region, and wherein the sixth region is located within the second blade and passes therethrough fresh air received from the fifth region; wherein each first region is in communication flow wise with a source of live steam during operation, and whereby each of the cooling circuits is effective to maximize cooling efficiency by delivering live steam to each of the cooling circuit first regions and by delivering fresh air through the fourth, fifth and sixth regions.