초록 ▼

A gas turbine engine turbine stage has an annular row of turbine airfoils including a first plurality of first airfoils having a first chord length and a second plurality of second airfoils having a second chord length shorter than the first chord length. At least one of the second airfoils is circu

A gas turbine engine turbine stage has an annular row of turbine airfoils including a first plurality of first airfoils having a first chord length and a second plurality of second airfoils having a second chord length shorter than the first chord length. At least one of the second airfoils is circumferentially disposed between each adjacent pair of the first airfoils. A second leading edges of the second airfoils are located downstream of first leading edges of the first airfoils. The first and second airfoils have different first and second temperature capabilities respectively and the first temperature capability is greater than the second temperature capability. The first and second airfoils may be made from different alloys and/or the second airfoils may be constructed to use lower amounts of cooling airflow than the first airfoils. More than one of the second airfoils may be disposed between each pair of the first airfoils.

대표청구항 ▼

Accordingly, what is desired to be secured by Letters Patent of the United States is the invention as defined and differentiated in the following claims: 1. A gas turbine engine turbine stage assembly comprising: an annular row of turbine airfoils including first and second pluralities of first and

Accordingly, what is desired to be secured by Letters Patent of the United States is the invention as defined and differentiated in the following claims: 1. A gas turbine engine turbine stage assembly comprising: an annular row of turbine airfoils including first and second pluralities of first and second turbine airfoils respectively, the first plurality of first turbine airfoils having a first chord length, the second plurality of second turbine airfoils having a second chord length shorter than the first chord length, at least one of the second turbine airfoils circumferentially disposed between each adjacent pair of the first turbine airfoils, second leading edges of the second turbine airfoils located downstream of first leading edges of the first turbine airfoils, and the first and second turbine airfoils having different first and second temperature capabilities respectively wherein the first temperature capability is greater than the second temperature capability. 2. An assembly as claimed in claim 1 wherein the first and second turbine airfoils are made from different alloys. 3. An assembly as claimed in claim 1 wherein the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 4. An assembly as claimed in claim 1 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 5. An assembly as claimed in claim 1 further comprising more than one of the second turbine airfoils circumferentially disposed between each adjacent pair of the first turbine airfoils, second leading edges of the second turbine airfoils located downstream of first leading edges of the first turbine airfoils, and the first and second turbine airfoils having different first and second temperature capabilities respectively wherein the first temperature capability is greater than the second temperature capability. 6. An assembly as claimed in claim 5 wherein the first and second turbine airfoils are made from different alloys. 7. An assembly as claimed in claim 5 wherein the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 8. An assembly as claimed in claim 5 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 9. A gas turbine engine turbine stage assembly comprising: axially adjacent annular upstream and downstream rows of turbine airfoils, the annular downstream row of the turbine airfoils includes a first plurality of first turbine airfoils having a first chord length and a second plurality of second turbine airfoils having a second chord length shorter than the first chord length, at least one of each of the second turbine airfoils circumferentially disposed between each adjacent pair of the first turbine airfoils, second leading edges of the second turbine airfoils located downstream of first leading edges of the first turbine airfoils, and the first and second turbine airfoils having different first and second temperature capabilities respectively wherein the first temperature capability is greater than the second temperature capability. 10. An assembly as claimed in claim 9 wherein the first and second turbine airfoils are made from different alloys. 11. An assembly as claimed in claim 9 wherein the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 12. An assembly as claimed in claim 9 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 13. An assembly as claimed in claim 9 further comprising more than one of the second turbine airfoils circumferentially disposed between each adjacent pair of the first turbine airfoils, second leading edges of the second turbine airfoils located downstream of first leading edges of the first turbine airfoils, and the first and second turbine airfoils having different first and second temperature capabilities respectively wherein the first temperature capability is greater than the second temperature capability. 14. An assembly as claimed in claim 13 wherein the first and second turbine airfoils are made from different alloys. 15. An assembly as claimed in claim 13 wherein the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 16. An assembly as claimed in claim 13 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 17. An assembly as claimed in claim 9 further comprising the annular upstream row of the turbine airfoils being in a first row of vanes and having a single airfoil chord length and the annular downstream row of the turbine airfoils being in a first rotor stage. 18. An assembly as claimed in claim 17 wherein the first and second turbine airfoils are made from different alloys. 19. An assembly as claimed in claim 17 wherein the second turbine airfoils include second internal cooling airflow circuits that use lower amounts of cooling airflow than second internal cooling airflow circuits in the first turbine airfoils. 20. An assembly as claimed in claim 17 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 21. An assembly as claimed in claim 17 further comprising more than one of the second turbine airfoils circumferentially disposed between each adjacent pair of the first turbine airfoils, second leading edges of the second turbine airfoils located downstream of first leading edges of the first turbine airfoils, and the first and second turbine airfoils having different first and second temperature capabilities respectively wherein the first temperature capability is greater than the second temperature capability. 22. An assembly as claimed in claim 21 wherein the first and second turbine airfoils are made from different alloys. 23. An assembly as claimed in claim 21 wherein the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils. 24. An assembly as claimed in claim 21 wherein the first and second turbine airfoils are made from different alloys and the second turbine airfoils are constructed to use lower amounts of cooling airflow than the first turbine airfoils.