US 11,913,349 B2
Gas turbine engine with high speed low pressure turbine section and bearing support features
Frederick M. Schwarz, Glastonbury, CT (US); Gabriel L. Suciu, Glastonbury, CT (US); William K. Ackermann, East Hartford, CT (US); Daniel Bernard Kupratis, Wallingford, CT (US); and Michael E. McCune, Colchester, CT (US)
Assigned to RTX CORPORATION, Farmington, CT (US)
Filed by RAYTHEON TECHNOLOGIES CORPORATION, Farmington, CT (US)
Filed on Feb. 1, 2023, as Appl. No. 18/104,375.
Application 18/104,375 is a continuation of application No. 16/227,271, filed on Dec. 20, 2018, granted, now 11,598,223.
Application 16/227,271 is a continuation of application No. 15/478,706, filed on Apr. 4, 2017, granted, now 10,287,914, issued on May 14, 2019.
Application 15/478,706 is a continuation in part of application No. 13/446,510, filed on Apr. 13, 2012, granted, now 9,611,859, issued on Apr. 4, 2017.
Application 13/446,510 is a continuation in part of application No. 13/363,154, filed on Jan. 31, 2012, abandoned.
Claims priority of provisional application 61/619,124, filed on Apr. 2, 2012.
Prior Publication US 2023/0167752 A1, Jun. 1, 2023
Int. Cl. F01D 25/16 (2006.01); F02K 3/06 (2006.01); F02C 3/107 (2006.01); F01D 15/12 (2006.01); F02C 7/06 (2006.01); F02C 7/20 (2006.01); F02C 7/36 (2006.01)
CPC F01D 25/164 (2013.01) [F01D 15/12 (2013.01); F01D 25/162 (2013.01); F02C 3/107 (2013.01); F02C 7/06 (2013.01); F02C 7/20 (2013.01); F02C 7/36 (2013.01); F02K 3/06 (2013.01); F05D 2220/32 (2013.01); F05D 2240/60 (2013.01); F05D 2260/40311 (2013.01)] 30 Claims
OG exemplary drawing
 
20. A turbofan engine comprising:
a fan including a plurality of fan blades, and an outer housing surrounding the fan to define a bypass flow path;
a low fan pressure ratio of less than 1.45 measured across the plurality of fan blades alone at a cruise condition at 0.8 Mach and 35,000 feet;
a compressor section including a first compressor and a second compressor;
a turbine section including a fan drive turbine and a second turbine, wherein the fan drive turbine includes three stages, the second turbine drives the second compressor, and the second turbine includes two stages;
an epicyclic gear system with a gear reduction and a gear reduction ratio of greater than 2.5:1, wherein the fan drive turbine drives the fan through the epicyclic gear system, wherein the epicyclic gear system includes a sun gear, a plurality of intermediate gears surrounding the sun gear, a carrier supporting the plurality of intermediate gears, and a ring gear surrounding the plurality of intermediate gears, and wherein the gear reduction is positioned between the fan drive turbine and the first compressor such that the fan and the first compressor are rotatable at a common speed;
a fan drive shaft interconnecting the gear system and the fan, and wherein first and second bearings are axially aligned with the fan drive shaft relative to an engine longitudinal axis, and the first and second bearings support a periphery of the fan drive shaft on opposite sides of the ring gear relative to the engine longitudinal axis;
wherein the fan drive turbine has a first exit area at a first exit point and is rotatable at a first speed, the second turbine has a second exit area at a second exit point and is rotatable at a second speed, the second speed being greater than twice the first speed; and
wherein a first performance quantity is defined as the product of the first speed squared and the first exit area, a second performance quantity is defined as the product of the second speed squared and the second exit area, and a performance ratio of the first performance quantity to the second performance quantity is no more than 1.5.