A gas turbine engine includes an epicyclic gear train that drives a turbo fan. The epicyclic gear train employs a one-piece carrier in which the spaced side walls are interconnected with circumferentially spaced apart mounts to form a unitary structure. Baffles are secured to the carrier near the mounts and provide lubrication passages that spray oil onto the sun gear and/or intermediate gears arranged between the baffles. The baffles can be constructed from a different material than the carrier since the baffles are not structural components in the gear train.

Oil baffle for gas turbine fan drive gear system

A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. A speed reduction device such as an epicyclical gear assembly may be utilized to drive the fan section such that the fan section may rotate at a speed different than the turbine section so as to increase the overall propulsive efficiency of the engine. In such engine architectures, a shaft driven by one of the turbine sections provides an input to the epicyclical gear assembly that drives the fan section at a speed different than the turbine section such that both the turbine section and the fan section can rotate at closer to optimal speeds providing increased performance attributes and performance by desirable combinations of the disclosed features of the various components of the described and disclosed gas turbine engine.

Geared turbofan gas turbine engine architecture

A turbofan engine includes a fan variable area nozzle includes having a first fan nacelle section and a second fan nacelle section movably mounted relative the first fan nacelle section. The second fan nacelle section axially slides aftward relative to the fixed first fan nacelle section to change the effective area of the fan nozzle exit area.

Gas turbine engine with axial movable fan variable area nozzle

A gas turbine engine includes a fan section, a gear arrangement configured to drive the fan section, a compressor section and a turbine section. The compressor section includes a low pressure compressor section and a high pressure compressor section. The turbine section is configured to drive compressor section and the gear arrangement. An overall pressure ratio, which is provided by a combination of a pressure ratio across said low pressure compressor section and a pressure ratio across said high pressure compressor section, is greater than about 35. The pressure ratio across the low pressure compressor section is between about 3 and about 8 whereas the pressure ratio across the high pressure compressor section is between about 7 and about 15.

Gas turbine engine compressor arrangement

A gas turbine engine includes a fan shaft and a support which supports the fan shaft. The support defines at least one of a support transverse and a support lateral stiffness. A gear system drives the fan shaft. A flexible support at least partially supports the gear system, and defines at least one of a flexible support transverse and a flexible support lateral stiffness with respect to at least one of the support transverse and the support lateral stiffness. An input to the gear system defines at least one of an input transverse and an input lateral stiffness with respect to at least one of the support transverse and the support lateral stiffness. A method of designing a gas turbine engine is also disclosed.

Flexible support structure for a geared architecture gas turbine engine

Weight and dimensional relationships that are used in aircraft preliminary design studies are analyzed. These relationships are relatively simple to prove useful to the preliminary designer, but they are sufficiently detailed to provide meaningful design tradeoffs. All weight and dimensional relationships are developed from data bases of existing and conceptual turbofan engines. The total propulsion system is considered including both engine and nacelle, and all estimating relations stem from physical principles, not statistical correlations.

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M. H. Waters

Papers

Analysis of turbofan propulsion system weight and dimensions