Abstract: A gas turbine engine (10) for an aircraft comprising: an engine core (11) comprising a turbine system comprising one or more turbines (17, 19), a compressor system comprising one or more compressors (14,15), and a core shaft (26) connecting the turbine system to the compressor system, wherein a compressor exit pressure (P30) is defined as an average pressure of airflow at the exit of the highest pressure compressor of the compressor system at cruise conditions, the engine core (11) further comprises an annular splitter (70) at which flow is divided between a core flow (A) that flows through the engine core and a bypass flow (B) that flows along a bypass duct (22), wherein stagnation streamlines (110) around the circumference of the engine (10), stagnating on a leading edge of the annular splitter (70), form a streamsurface (110) forming a radially outer boundary of a streamtube that contains all of the core flow (A); a fan (23) located upstream of the engine core (11), the fan comprising a plurality of fan bl

Abstract: A gas turbine engine includes: an engine core, compressor system, and core shaft. A compressor exit pressure is defined as an average airflow pressure at the exit of the highest pressure compressor at cruise conditions. The core has an annular splitter and bypass flow. Stagnation streamlines around the engine circumference form a streamsurface. A fan is upstream the core with blades having leading and trailing edges, and a radially inner portion within the streamtube. A fan root entry pressure is an average airflow pressure across the radially inner portion leading edge of each fan blade at cruise conditions. An overall pressure ratio is defined as the compressor exit pressure divided by the fan root entry pressure. A bypass jet velocity is defined as the jet velocity of air flow exiting the bypass exhaust nozzle at cruise conditions. A jet velocity is in a range between 4.7 m/s and 7.7 m/s.

Abstract: A gas turbine engine for an aircraft includes an engine core including a first, lower pressure, turbine, a first compressor, and a first core shaft connecting the first turbine to the first compressor; and a second, higher pressure, turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor, and a fan located upstream of the engine core and comprising a plurality of fan blades extending from a hub. First and second turbine entrance and exit temperatures are defined as average temperature of airflow at the entrance or exit to the respective turbine at cruise conditions. A low pressure turbine temperature change is defined as: the ? ? first ? ? turbine ? ? entrance ? ? temperature the ? ? first ? ? turbine ? ? exit ? ? temperature .

Abstract: An engine core including turbine, compressor, and core shaft connecting the turbine to the compressor, wherein a compressor exit temperature has an average airflow; and a fan upstream including a plurality of fan blades extending from a hub, each fan blade having a leading and trailing edge, wherein a fan rotor entry temperature has an average airflow across the leading edge of each blade at cruise conditions and fan tip rotor exit temperature has an average temperature of airflow across a radially outer portion of each blade at the trailing edge cruise conditions. A fan tip temperature rise as: the ? ? fan ? ? tip ? ? rotor ? ? exit ? ? temperature the ? ? fan ? ? rotor ? ? entry ? ? temperature .

Abstract: A gas turbine engine includes an engine core including a turbine, compressor, and core shaft connecting the turbine to compressor, wherein a compressor exit temperature defined as an average temperature of airflow at exit from compressor at cruise conditions and a core entry temperature defined as an average temperature of airflow entering engine core at cruise conditions, and a fan located upstream of the engine core, wherein a fan rotor entry temperature defined as an average temperature of airflow across leading edge each fan blade at cruise conditions and fan tip rotor exit temperature defined as an average temperature of airflow across a radially outer portion of each fan blade at the trailing edge at cruise conditions. A core compressor temperature rise defined as: the ? ? compressor ? ? exit ? ? temperature the ? ? core ? ? entry ? ? temperature .

Abstract: A gas turbine engine for an aircraft includes an engine core with a turbine, compressor, and core shaft connecting the two; and a fan upstream of the core with a plurality of blades extending from a hub each with a leading and trailing edge, wherein fan tip radius is between the engine centreline and each blade's leading edge outermost tip and hub radius is between the engine centreline and the hub's outer surface at each blade's leading edge radial position, the ratio of hub to tip radius between 0.2 and 0.285. A fan rotor entry temperature is the average temperature of airflow across the leading edge of each blade at cruise conditions and a fan rotor exit temperature is an average temperature of airflow across a radially outer portion of each blade at the trailing edge at cruise conditions, the ratio of entry to exit temperature between 1.11 and 1.05.

Abstract: A gas turbine engine for an aircraft includes an engine core including a turbine, compressor, and core shaft, wherein a compressor exit temperature is defined as an average temperature of airflow at the exit from the compressor at cruise conditions and a core entry temperature is defined as an average temperature of airflow entering the engine core at cruise conditions. A fan rotor entry temperature is defined as an average temperature of airflow across the leading edge of each fan blade at cruise conditions. A core compressor temperature rise is defined as the compressor exit temperature divided by the core entry temperature. A fan root temperature rise is defined as the core entry temperature divided by the fan rotor entry temperature. A core compressor to fan root temperature rise ratio is in a specified range.

Abstract: A gas turbine engine for an aircraft includes an engine core including a first, lower pressure, turbine, a first compressor, and a first core shaft connecting the first turbine to the first compressor; and a second, higher pressure, turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor, and a fan located upstream of the engine core and including a plurality of fan blades extending from a hub. A low pressure turbine temperature change is defined as: the ? ? first ? ? turbine ? ? exit ? ? temperature the ? ? first ? ? turbine ? ? entrance ? ? temperature . A fan tip temperature rise is defined as: the ? ? fan ? ? tip ? ? rotor ? ? exit ? ? temperature the ? ? fan ? ? rotor ? ? entry ? ? temperature .

Abstract: A gas turbine engine includes: an engine core, compressor system, and core shaft. A compressor exit pressure is defined as an average airflow pressure at the exit of the highest pressure compressor at cruise conditions. The core has an annular splitter and bypass flow. Stagnation streamlines around the engine circumference form a streamsurface. A fan is upstream the core with blades having leading and trailing edges, and a radially inner portion within the streamtube. A fan root entry pressure is an average airflow pressure across the radially inner portion leading edge of each fan blade at cruise conditions. An overall pressure ratio, OPR, is defined as the compressor exit pressure divided by the fan root entry pressure. A bypass jet velocity is defined as the jet velocity of air flow exiting the bypass exhaust nozzle at cruise conditions. A jet velocity to OPR ratio is in a range between 4.7 m/s and 7.7 m/s.

Abstract: A highly efficient gas turbine engine includes a fan which is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine is provided. The fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine has a fan that is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine is a system wherein the fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine includes a fan driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine includes a fan which is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine includes the fan of the gas turbine engine driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine is provided. The fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A gas turbine engine is highly efficient. The fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

Abstract: A highly efficient gas turbine engine includes a fan which is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, which results in efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.