Abstract:
A thermal system for a gas turbine engine includes a bypass flow duct and a compressor flow duct which meets with the bypass flow duct at an intersection. A valve is located within the intersection and is movable between a first position and a second position. First position is operable to selectively communicate fan bypass flow from the bypass flow duct and block the compressor flow duct. The second position is operable to selectively block the bypass flow duct and communicate bleed flow through the compressor flow duct.
Abstract:
A gas turbine engine including a core nacelle defined about an engine axis. A fan nacelle is mounted at least partially around the core nacelle to define a fan bypass airflow path for a fan bypass airflow. A gear train is defined along an engine axis. The gear train defines a gear reduction ratio of greater than or equal to about 2.3. A spool along the engine axis drives the gear train. The spool includes a downstream turbine having six or fewer stages. A fan is driven through the gear train by the downstream turbine. A pressure ratio across the fan is less than about 1.45. A fan variable area nozzle is axially movable relative to the fan nacelle to vary a fan nozzle exit area and adjust a pressure ratio of the fan bypass airflow during engine operation.
Abstract:
A gas turbine engine comprises a gear train defined along an engine axis. A spool along the engine axis drives the gear train, and includes a low stage count downstream turbine. A fan rotates at a fan speed about the engine axis and drives the downstream turbine through the gear train. The fan speed is less than a speed of the downstream turbine. A core is surrounded by a core housing defined about the engine axis. A fan nacelle is mounted around the core nacelle to define a fan bypass airflow path for a fan bypass airflow. A bypass ratio defined by the fan bypass passage airflow divided by airflow through the core is greater than about ten (10).
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 or equal to about 8 at cruise power. A gear arrangement is configured to drive the fan section. A compressor section includes both a first compressor section and a second compressor section. A turbine section is configured to drive the gear arrangement, and may have a low pressure turbine with four stages and a low pressure turbine pressure ratio greater than about 5:1, and a high pressure turbine with two stages. An overall pressure ratio is provided by the combination of a pressure ratio across the first compressor section and a pressure ratio across the second compressor section, and greater than about 40, measured at sea level and at a static, full-rated takeoff power. The pressure ratio across the second compressor section is greater than about 7.
Abstract:
An accessory system for a gas turbine engine includes an accessory gearbox which defines an accessory gearbox axis and includes first and second sides. A first geartrain includes one or more shafts rotatable about axes perpendicular to the first side of the accessory gearbox and a second geartrain includes one or more shafts rotatable about axes perpendicular to the second side of the accessory gearbox. A driven gear set defines an input axis and drives first geartrain and the second geartrain about corresponding first and second drive axes parallel to the input axis.
Abstract:
A gas turbine engine comprises a gear train defined along an axis. A spool along the axis drives the gear train and includes a low stage count low pressure turbine. A fan i s rotatable at a fan speed about the axis and driven by the low pressure turbine through the gear train. The fan speed is less than a speed of the low pressure turbine. A core is surrounded by a core nacelle defined about the axis. A fan nacelle i s mounted at least partially around the core nacelle to define a fan bypass airflow path for a fan bypass airflow. A bypass ratio defined by the fan bypass passage airflow divided by airflow through the core is greater than about ten (10).
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, with the overall pressure ratio being greater than or equal to about 35. 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 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. The turbine section includes a fan drive turbine configured to drive the fan section, a pressure ratio across the fan drive turbine being greater than or equal to about 5. An overall pressure ratio is provided by the combination of the first compressor and the second compressor.
Abstract:
A gas turbine engine has a fan section, a gear arrangement configured to drive the fan section, a compressor section, including both a low pressure compressor section and a high pressure compressor section. A turbine section is configured to drive the compressor section and the gear arrangement. An overall pressure ratio provided by the combination of a pressure ratio across the low pressure compressor section and a pressure ratio across the high pressure compressor section is greater than about 35. The pressure ratio across a first of the low and high pressure compressor sections is between about 3 and about 8. The pressure ratio across a second of the low and high pressure compressor sections is between about 7 and about 15. The fan is configured to deliver a portion of air into the compressor section, and a portion of air into a bypass duct.
Abstract:
A gas turbine engine includes an engine static structure housing that includes a compressor section and a turbine section. A combustor section is arranged axially between the compressor section and the turbine section. A core nacelle encloses the engine static structure to provide a core compartment. An oil tank is arranged in the core compartment and is axially aligned with the compressor section. A heat exchanger is secured to the oil tank and arranged in the core compartment.