Thrust efficient turbofan engine

Patent metadata

Field	Value
Publication number	US-9624827-B2
Application number	US-201313854225-A
Country	US
Kind code	B2
Filing date	Apr 1, 2013
Priority date	Mar 15, 2013
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

A turbofan engine includes a gas generator section for generating a gas stream flow with higher energy per unit mass flow than that contained in the ambient air and a power turbine that converts the gas stream flow into shaft power. The turbofan engine further includes a propulsor section including a fan driven by the power turbine through a geared architecture 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. An Engine Unit Thrust Parameter 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 is less than about 0.15 at a take-off condition.

First claim

What is claimed is:

1. A turbofan engine comprising:
a gas generator section for generating a gas stream flow with higher energy per unit mass flow than that contained in ambient air;
a power turbine converting the gas stream flow into shaft power, the power turbine rotating at a first rotational speed;
a speed reduction device driven by the power turbine; and
a propulsor section including 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, wherein 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 is less than about 0.15 at a take-off condition.

2. The turbofan engine as recited in claim 1 , wherein the EUTP at one of a climb condition and a cruise condition is less than about 0.10.

3. The turbofan engine as recited in claim 1 , wherein the EUTP at one of a climb condition and a cruise condition is less than about 0.08.

4. The turbofan engine as recited in claim 1 , wherein the tip diameter of the fan is between about 50 inches and about 160 inches.

5. The turbofan engine as recited in claim 1 , wherein the mass flow generated by the propulsor section is between about 625 lbm/hour and about 80,000 lbm/hour.

6. The turbofan engine as recited in claim 1 , wherein the first speed of the power turbine is between about 6200 rpm and about 12,500 rpm.

7. The turbofan engine as recited in claim 1 , wherein the propulsive thrust generated by the turbofan engine is between about 16,000 lbf and about 120,000 lbf.

8. The turbofan engine as recited in claim 7 , wherein the gas generator defines an overall pressure ratio of between about 40 and about 80.

9. A turbofan engine comprising:
a gas generator section for generating a gas stream flow with higher energy per unit mass flow than that contained in ambient air;
a power turbine converting the gas stream flow into shaft power, the power turbine rotating at a first rotational speed;
a speed reduction device driven by the power turbine; and
a propulsor section including 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, wherein 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 is less than about 0.10 at one of a climb condition and a cruise condition.

10. The turbofan engine as recited in claim 9 , wherein the EUTP at one of the climb condition and the cruise condition is less than about 0.08.

11. The turbofan engine as recited in claim 9 , wherein the EUTP at a take-off condition is less than about 0.15.

12. The turbofan engine as recited in claim 9 , wherein the tip diameter of the fan is between about 50 inches and about 160 inches.

13. The turbofan engine as recited in claim 9 , wherein the mass flow generated by the propulsor section is between about 625 lbm/hour and about 80,000 lbm/hour.

14. The turbofan engine as recited in claim 1 , wherein the first speed of the power turbine is between about 6200 rpm and about 12,500 rpm.

15. The turbofan engine as recited in claim 9 , wherein the propulsive thrust generated by the turbofan engine is between about 16,000 lbf and about 120,000 lbf.

16. The turbofan engine as recited in claim 9 , wherein the gas generator defines an overall pressure ratio of between about 40 and about 80.

17. A turbofan engine comprising:
a gas generator section for generating a high energy gas stream, the gas generating section including a compressor section, combustor section and a first turbine;
a second turbine converting the high energy gas stream flow into shaft power, the second turbine rotating at a first speed and including less than or equal to about six (6) stages;
a geared architecture driven by the second turbine; and
a propulsor section driven by the second turbine through the geared architecture at a second speed lower than the first speed, the propulsor section including a fan with a pressure ratio across the fan section less than about 1.45, the propulsor section generating propulsive thrust as a mass flow rate of air through a bypass flow path from the shaft power, wherein an Engine Unit Thrust Parameter (“EUTP”) defined as net engine thrust divided by a product of a mass flow rate of air through the bypass flow path, a tip diameter of the fan and the first rotational speed of the second turbine is less than about 0.15 at a take-off condition.

18. The turbofan engine as recited in claim 17 , wherein the EUTP at one of a climb condition and a cruise condition is less than about 0.10.

19. The turbofan engine as recited in claim 17 , wherein the EUTP at the take-off condition is less than about 0.08.

20. The gas turbofan engine as recited in claim 17 , wherein the fan section defines a bypass airflow having a bypass ratio greater than about ten (10).

21. The turbofan engine as recited in claim 17 , wherein the tip diameter of the fan is between about 50 inches and about 160 inches.

22. The turbofan engine as recited in claim 17 , wherein the mass flow generated by the propulsor section is between about 625 lbm/hour and about 80,000 lbm/hour.

23. The turbofan engine as recited in claim 17 , wherein the first speed of the second turbine is between about 6200 rpm and about 12,500 rpm.

24. The turbofan engine as recited in claim 17 , wherein the second turbine comprises a low pressure turbine with 3 to 6 stages.

Assignees

• United Technologies Corp

Inventors

• Sabnis Jayant

Classifications

• F05D2220/36

  specially adapted for the fan of turbofan engines · CPC title

• F02K1/52 Primary

  Nozzles specially constructed for positioning adjacent to another nozzle or to a fixed member, e.g. fairing · CPC title

• F02K3/06

  with front fan · CPC title

• F02C3/08

  the compressor comprising at least one radial stage (F02C3/10 takes precedence) · CPC title

• F02C7/36

  Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) · CPC title