Method of operating a rotary engine

Patent metadata

Field	Value
Publication number	US-10815877-B2
Application number	US-201715408784-A
Country	US
Kind code	B2
Filing date	Jan 18, 2017
Priority date	Jan 18, 2017
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

A method of operating a rotary engine including a rotor engaged to a shaft and rotationally received in a housing to define a plurality of working chambers of variable volume, including delivering a pilot quantity of fuel into a pilot cavity in successive communication with the working chambers, igniting the pilot quantity of fuel within the pilot cavity, and delivering a main quantity of fuel into the working chambers downstream of the successive communication of the pilot cavity with the working chambers, where at least one of the pilot quantity and the main quantity is varied between successive rotations of the shaft.

First claim

The invention claimed is:

1. A method of operating a rotary engine including a rotor engaged to a shaft and rotationally received in a housing to define a plurality of working chambers of variable volume, the method comprising:
delivering a pilot quantity of fuel into a pilot cavity in successive communication with the working chambers;
igniting the pilot quantity of fuel within the pilot cavity; and
delivering a main quantity of fuel into the working chambers downstream of the successive communication of the pilot cavity with the working chambers;
wherein at least one of the pilot quantity and the main quantity is varied between successive rotations of the shaft,
wherein the at least one of the pilot quantity and the main quantity is zero for at least one of the successive rotations of the shaft and greater than zero for at least another one of the successive rotations of the shaft.

2. The method as defined in claim 1 , wherein the pilot cavity is a pilot subchamber.

3. The method as defined in claim 1 , wherein for each set of first, second and third successive rotations of the shaft, the main quantity is zero and the pilot quantity is greater than zero during the first rotation, the main and pilot quantities are zero during the second rotation, and the main and pilot quantities are greater than zero during the third rotation.

4. The method as defined in claim 1 , wherein the pilot quantity is zero for one of x successive rotations of the shaft and greater than zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

5. The method as defined in claim 1 , wherein the pilot quantity is greater than zero for one of x successive rotations of the shaft and zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

6. The method as defined in claim 1 , wherein the main quantity is zero for one of x successive rotations of the shaft and greater than zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

7. The method as defined in claim 1 , wherein the main quantity is greater than zero for one of x successive rotations of the shaft and zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

8. The method as defined in claim 1 , wherein the main quantity includes first and second successive injection pulses for each of the working chambers, and wherein one of the first and second injection pulses is omitted for one of x successive rotations of the shaft and performed for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

9. The method as defined in claim 1 , wherein the main quantity includes first and second successive injection pulses for each of the working chambers, and wherein one of the first and second injection pulses is performed for one of x successive rotations of the shaft and omitted for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

10. The method as defined in claim 1 , wherein the rotary engine is a Wankel engine, the rotor having three apex portions separating the working chambers and mounted for eccentric revolutions within an internal cavity of the housing, the internal cavity having an epitrochoid shape with two lobes.

11. A method of operating a rotary engine including first and second rotor assemblies and a shaft, the first and second rotor assemblies including a rotor engaged to the shaft and rotationally received in a housing to define a plurality of working chambers of variable volume, and a pilot cavity in successive communication with the working chambers, the method comprising:
delivering a pilot quantity of fuel into the pilot cavity;
igniting the pilot quantity of fuel within the pilot cavity; and
delivering a main quantity of fuel into the working chambers downstream of the successive communication of the pilot cavity with the working chambers;
wherein at least one of the pilot quantity and the main quantity of the first rotor assembly is varied between successive rotations of the shaft;
wherein at least one of the pilot quantity and the main quantity is different between the first and second rotor assemblies during at least one of the successive rotations of the shaft, and wherein the at least one of the pilot quantity and the main quantity of the first rotor assembly is zero for at least one of the successive rotations of the shaft and greater than zero for at least another one of the successive rotations of the shaft.

12. The method as defined in claim 11 , wherein the pilot cavity is a pilot subchamber.

13. The method as defined in claim 11 , wherein for each set of first, second and third successive rotations of the shaft, the main quantity of the first rotor assembly is zero and the pilot quantity is greater than zero during the first rotation, the main and pilot quantities of the first rotor assembly are zero during the second rotation, and the main and pilot quantities of the first rotor assembly are greater than zero during the third rotation.

14. The method as defined in claim 11 , wherein the pilot quantity of the first rotor assembly is zero for one of x successive rotations of the shaft and greater than zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

15. The method as defined in claim 11 , wherein the pilot quantity of the first rotor assembly is greater than zero for one of x successive rotations of the shaft and zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

16. The method as defined in claim 11 , wherein the main quantity of the first rotor assembly is zero for one of x successive rotations of the shaft and greater than zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

17. The method as defined in claim 11 , wherein the main quantity of the first rotor assembly is greater than zero for one of x successive rotations of the shaft and zero for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

18. The method as defined in claim 11 , wherein the main quantity of the first rotor assembly includes first and second successive injection pulses for each of the working chambers, and wherein one of the first and second injection pulses is omitted for one of x successive rotations of the shaft and performed for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

19. The method as defined in claim 11 , wherein the main quantity of the first rotor assembly includes first and second successive injection pulses for each of the working chambers, and wherein one of the first and second injection pulses is performed for one of x successive rotations of the shaft and omitted for the remaining x−1 successive rotations of the shaft, where x is a natural number greater than 1.

20. The method as defined in claim 11 , wherein the first and second rotor assemblies are Wankel engines, the rotor having three apex portions separating the working chambers and mounted for eccentric revolutions within an internal cavity of the housing, the internal cavity having an epitrochoid shape with two lobes.

21. The method as defined in claim 11 , further comprising a third rotor assembly engaged to the shaft, wherein the at least one of the pilot quantity

Assignees

• Pratt & Whitney Canada

Inventors

• Julien Andre
• Schulz Edwin

Classifications

• F02B53/10 Primary

  Fuel supply; Introducing fuel to combustion space · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02B53/02 Primary

  Methods of operating · CPC title

• F02B2053/005

  Wankel engines · CPC title

• F02B19/10

  with fuel introduced partly into pre-combustion chamber, and partly into cylinder · CPC title