Thrust efficient turbofan engine
AssigneeUnited Technologies Corporation
InventorJayant Sabnis
Life of this patent
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Abstract
A disclosed turbofan engine includes a gas generator section for generating a gas stream flow. A speed reduction device is driven by the power turbine. A propulsor section includes a fan driven by the power turbine through the speed reduction device at a second speed lower than the first speed for generating propulsive thrust as a mass flow rate of air through a bypass flow path. The fan includes a tip diameter greater than about forty-five (45) inches and an Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of the mass flow rate of air through the bypass flow path, a tip diameter of the fan and the first rotational speed of the power turbine for cruise, climb and take-off power conditions.
Claims26
A turbofan engine comprising:
- a propulsor section including a fan, wherein the fan includes a fan tip diameter greater than 50 inches and less than 160 inches and less than 26 fan blades;
- a low speed spool having an inner shaft and a power turbine;
- a high speed spool having an outer shaft concentric about the inner shaft;
- a geared architecture in driving connection between the power turbine and the fan, wherein the geared architecture has a gear ratio greater than 2.3;
- and
- an Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of a mass flow rate of air through a bypass flow path, a tip diameter of the fan and a first rotational speed of the power turbine in operation that is less than 0.25 at a sea level takeoff power condition, wherein a mass flow generated through a bypass passage by the propulsor section is between about 625 lbm/sec and about 80,000 lbm/sec, the mass flow rate of air through the bypass flow path is between 625 lbm/sec and 80,000 lbm/sec and the first rotational speed is between 6,200 rpm and 12,500 rpm.
A turbofan engine comprising:
- a propulsor section including a fan, wherein the fan includes a fan tip diameter greater than 50 inches and less than 160 inches;
- a power turbine having a plurality of stages;
- and
- a geared architecture in driving connection between the power turbine and the fan, wherein the geared architecture has a gear ratio greater than 2.3;
- wherein an Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of a mass flow rate of air through a bypass flow path, a tip diameter of the fan and a first rotational speed of the power turbine in operation is less than 0.15 at a cruise condition, and less than 0.25 at a sea level takeoff power condition, wherein the net engine thrust is between 16,000 lbf and 120,000 lbf, the mass flow rate of air through the bypass flow path is between 625 lbm/sec and 80,000 lbm/sec and the first rotational speed is between 6,200 rpm and 12,500 rpm.
A turbofan engine comprising:
- a propulsor section including a fan and a low fan pressure ratio across the fan alone that is less than 1.45 in operation, wherein the fan includes a fan tip diameter greater than 50 inches and less than 160 inches and less than 26 fan blades;
- a low speed spool having an inner shaft and a high speed spool having an outer shaft concentric about the inner shaft;
- a power turbine part of the low spool including from three (3) to six (6) stages;
- a geared architecture in driving connection between the power turbine and the fan, wherein an Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of a mass flow rate of air through a bypass flow path, a tip diameter of the fan and a first rotational speed of the power turbine in operation is less than 0.15 at a sea level takeoff power condition, wherein the net engine thrust is between 16,000 lbf and 120,000 lbf, the mass flow rate of air through the bypass flow path is between 625 lbm/sec and 80,000 lbm/sec and the first rotational speed is between 6,200 rpm and 12,500 rpm.
Dependencies are inferred from the claim text.