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US 2019/0195140 A1Published application
Fundamental gear system architecture
AssigneeUnited Technologies Corporation
InventorWilliam G. Sheridan
Life of this patent
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Abstract
A fan drive gear system for a gas turbine engine includes a gear system that provides a speed reduction between a fan drive turbine and a fan and a mount flexibly supporting portions of the gear system. A lubrication system supporting the fan drive gear system provides lubricant to the gear system and removes thermal energy produced by the gear system. The lubrication system includes a capacity for removing thermal energy equal to less than about 2% of power input into the gear system.
Claims20
A gas turbine engine comprising:
- a fan including a plurality of fan blades rotatable about an axis;
- a fan pressure ratio across a fan blade alone of less than 1.45;
- a bypass duct;
- a compressor section;
- a bypass ratio greater than ten (10), the bypass ratio being defined as the portion of air delivered into the bypass duct divided by the amount of air delivered into the compressor section;
- a combustor in fluid communication with the compressor section;
- a fan drive turbine in communication with the combustor, the fan drive turbine comprising a pressure ratio greater than about 5, wherein the fan drive turbine further includes an inlet having an inlet pressure, and an outlet that is prior to any exhaust nozzle and having an outlet pressure, and the pressure ratio of the fan drive turbine is a ratio of the inlet pressure to the outlet pressure;
- a gear system providing a speed reduction between the fan drive turbine and the fan and transferring power input from the fan drive turbine to the fan at an efficiency greater than 98%, wherein the gear system further comprises a gear reduction ratio of greater than 2.3;
- a lubrication system providing lubricant to rotating components of the engine including the gear system and removing thermal energy from the lubricant, wherein the lubrication system comprises a first lubrication system providing lubricant flow to the gear system, and a second lubrication system supplementing operation of the first lubrication system by providing supplementary lubricant flow to the gear system in response to an interruption in lubricant flow from the first lubrication system;
- and
- a second turbine is in communication with the combustor, wherein the second turbine is a two stage turbine, and the fan drive turbine includes less than six turbine rotors.
8 more elements
A gas turbine engine comprising:
- a fan including less than twenty (20) fan blades rotatable about an axis;
- a compressor section;
- a combustor in communication with the compressor section;
- a bypass duct and a bypass ratio of a portion of air delivered into the bypass duct divided by the amount of air delivered into the compressor section is greater than ten (10);
- a fan drive turbine in communication with the combustor, the fan drive turbine comprising less than six (6) fan drive turbine rotors, an inlet having an inlet pressure, an outlet prior to any exhaust nozzle and having an outlet pressure, a pressure ratio of the inlet pressure to the outlet pressure greater than about five (5), and a ratio of between the number of fan blades and the number of fan drive turbine rotors is between 3.3 and 8.6;
- a bearing system supporting rotation of an inner shaft driven by the fan drive turbine and an outer shaft driven by a second turbine;
- a fan drive gear system providing a speed reduction between the fan drive turbine and the fan of greater than 2.3, the fan drive gear system transferring power input from the fan drive turbine to the fan at an efficiency greater than 98% and less than 100%;
- a lubrication system circulating lubricant to at least the bearing system and the fan drive gear system, the lubrication system has a maximum capacity for removing thermal energy from the lubricant equal of no more than 2% of power input into the fan drive gear system by the fan drive turbine during operation of the engine.
5 more elements
A gas turbine engine comprising:
- a fan including a plurality of fan blades rotatable about an axis and surrounded by a housing defining a bypass duct, wherein a fan pressure ratio across the plurality of fan blades alone is less than 1.45;
- a compressor section axially aft of the fan;
- a bypass ratio greater than ten (10), the bypass ratio being defined as the portion of air delivered into the bypass duct divided by the amount of air delivered into the compressor section;
- a combustor in fluid communication with the compressor section;
- a turbine section including a fan drive turbine and a second turbine in communication with the combustor;
- a fan drive gear system providing a speed reduction between the fan drive turbine and the fan and transferring power input from the fan drive turbine to the fan at an efficiency greater than 98% and less than 100%, wherein the fan drive gear system further comprises a gear reduction ratio of greater than 2.3;
- an input shaft arranged in a driving relationship to the fan drive turbine;
- a gear support system including a flexible support structure supporting at least one gear of the gear system relative to the input shaft;
- a lubrication system providing lubricant to rotating components of the engine including the gear system and removing thermal energy from the lubricant, the lubrication system has a maximum capacity for removing thermal energy from the lubricant equal of no more than 2% of power input into the fan drive gear system by the fan drive turbine during operation of the engine, wherein the lubrication system comprises a first lubrication system providing lubricant flow to the fan drive gear system and a second lubrication system supplementing operation of the first lubrication system by providing supplementary lubricant flow to at least the fan drive gear system in response to an interruption in lubricant flow from the first lubrication system.
6 more elements
Dependencies are inferred from the claim text.