Abstract:
A gas turbine engine includes, among other things, a fan section, a core engine, a bypass passage, and a bypass ratio defined as the volume of air passing into the bypass passage compared to the volume of air passing into the core engine, the bypass ratio being greater than 8 at cruise power. A gear arrangement drives the fan section. A guide vane includes a forward attachment, the forward attachment positioned aft of a plumbing connection area. A compressor section includes both a first compressor and a second compressor. A lubrication system and a compressed air system are in fluid communication with the gear arrangement. A turbine section drives the gear arrangement, and includes a low pressure turbine. An overall pressure ratio is provided by the combination of a pressure ratio across the first compressor and a pressure ratio across the second compressor, and greater than about 50, measured at sea level and at a static, full-rated takeoff power. The pressure ratio across the second compressor is greater than about 7.
Abstract:
A gas turbine engine includes a housing includes an inlet case and an intermediate case that respectively provide an inlet case flow path and an intermediate case flow path. A rotor is connected to the hub and supports a compressor section. The geared architecture includes an epicyclic gear train. A fan is rotationally driven by the geared architecture. First and second bearings support the shaft relative to the intermediate case and the inlet case, respectively. The radially inner boundary of the core inlet is at a location of a core inlet stator and the radially inner boundary of the compressor section inlet is at a location of the first stage low-pressure compressor rotor.
Abstract:
A turbofan engine includes a fan driven by a low pressure turbine through a gear reduction. The gear reduction has a gear ratio of greater than or equal to about 2.4. The low pressure turbine has an expansion ratio greater than or equal to about 5. The fan has a bypass ratio greater than or equal to about 8. In other features, a turbofan engine includes a variable geometry fan exit guide vane (FEGV) system having a multiple of circumferentially spaced radially extending fan exit guide vanes. Rotation of the fan exit guide vanes between a nominal position and a rotated position selectively changes a fan bypass flow path to permit efficient operation at various flight conditions.
Abstract:
A gas turbine engine includes a fan section including a fan rotatable about an axis. A speed reduction device is connected to the fan. The speed reduction device includes a planetary fan drive gear system with a planet gear ratio of at least 2.5. A bypass ratio is greater than about 11.0.
Abstract:
A gas turbine engine has a fan section, including a fan, a gear arrangement configured to drive the fan section, and a compressor section, including both a first compressor and a second compressor. A turbine section is configured to drive the compressor section and the gear arrangement. An overall pressure ratio is provided by the combination of the first compressor and the second compressor. The fan is configured to deliver a portion of air into the compressor section, and a portion of air into a bypass duct. A bypass ratio which is defined as a volume of air passing to the bypass duct compared to a volume of air passing into the compressor section is greater than or equal to about 8.
Abstract:
A gas turbine engine includes a housing includes an inlet case and an intermediate case that respectively provide an inlet case flow path and an intermediate case flow path. A rotor is connected to the hub and supports a compressor section. The geared architecture includes an epicyclic gear train. A fan is rotationally driven by the geared architecture. First and second bearings support the shaft relative to the intermediate case and the inlet case, respectively. The radially inner boundary of the core inlet is at a location of a core inlet stator and the radially inner boundary of the compressor section inlet is at a location of the first stage low-pressure compressor rotor.
Abstract:
A gas turbine engine includes a fan section that includes a fan rotatable about an axis of rotation of the gas turbine engine. A speed reduction device is connected to the fan. The speed reduction device includes a star drive gear system with a star gear ratio of at least 1.5. A bypass ratio is greater than about 11.0.
Abstract:
A gas turbine engine includes an engine centerline longitudinal axis and a fan section including a fan with fan blades and rotatable about the engine centerline longitudinal axis. A low corrected fan tip speed less than about 1400 ft/sec and the low corrected fan tip speed is an actual fan tip speed determined at an ambient temperature divided by [(Tram ° R)/(518.7 ° R)]0.5, where T represents the ambient temperature in degrees Rankine. A bypass ratio greater than about 11 and a speed reduction device having a gear system with a gear ratio. A low and high pressure turbine in communication with a first and second shaft, respectively. The first and second shafts are concentric and mounted via at least one of the bearing systems for rotation about the engine centerline longitudinal axis and the first shaft is in communication with the fan through the speed reduction device and the low pressure turbine includes four stages.
Abstract:
A gas turbine engine includes an engine centerline longitudinal axis and a fan section including a fan with fan blades and rotatable about the engine centerline longitudinal axis. A low corrected fan tip speed less than about 1400 ft/sec and the low corrected fan tip speed is an actual fan tip speed determined at an ambient temperature divided by [(Tram ° R)/(518.7° R)]0.5, where T represents the ambient temperature in degrees Rankine. A bypass ratio greater than about 11 and a speed reduction device having a gear system with a gear ratio. A low and high pressure turbine in communication with a first and second shaft, respectively. The first and second shafts are concentric and mounted via at least one of the bearing systems for rotation about the engine centerline longitudinal axis and the first shaft is in communication with the fan through the speed reduction device and the low pressure turbine includes four stages.
Abstract:
A gas turbine engine has a fan section including a fan rotatable about an axis. A speed reduction device is in communication with the fan. The speed reduction device includes a planetary fan drive gear system with a planet gear ratio of at least 2.6. A fan blade tip speed of the fan is less than 1400 fps. A low pressure turbine section is in communication with the speed reduction device. The low pressure turbine section includes three or four stages. A bypass ratio is between 11.0 and about 22.0. A method of improving performance of a gas turbine engine comprising