GAS TURBINE ENGINE WITH HIGH SPEED LOW PRESSURE TURBINE SECTION
A gas turbine engine includes a very high speed low pressure turbine such that a quantity defined by the exit area of the low pressure turbine multiplied by the square of the low pressure turbine rotational speed compared to the same parameters for the high pressure turbine is at a ratio between about 0.5 and about 1.5.
1 - 6 . (canceled)
7 . A gas turbine engine comprising:
a fan;
a compressor section in fluid communication with the fan;
a combustion section in fluid communication with the compressor section;
a turbine section in fluid communication with the combustion section,
wherein the turbine section includes a first turbine section and a second turbine section,
wherein said first turbine section has a first exit area at a first exit point and rotates at a first speed,
wherein said second turbine section has a second exit area at a second exit point and rotates at a second speed, which is higher than the first speed,
wherein a first performance quantity is defined as the product of the first speed squared and the first area,
wherein a second performance quantity is defined as the product of the second speed squared and the second area:
wherein a ratio of the first performance quantity to the second performance quantity is between about 0.5 and about 1.5; and
a gear reduction is included between said fan and a low spool driven by the first turbune section such that the fan rotates at a lower speed than the first turbine section.
8 - 11 . (canceled)
12 . The engine as set forth in claim 7 , wherein a gear ratio of said gear reduction is greater than about 2.3.
13 . The engine as set forth in claim 12 , wherein said gear ratio is greater than about 2.5.
14 - 20 . (canceled)