Compound engine system with rotary engine

Patent metadata

Field	Value
Publication number	US-9759126-B2
Application number	US-201514701809-A
Country	US
Kind code	B2
Filing date	May 1, 2015
Priority date	Jul 28, 2011
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A compound engine system including a Wankel engine having a recess defined in the peripheral wall of the rotor in each of the three rotating chambers, the recess having a volume of more than 5% of the displacement volume of the chambers. The expansion in the turbine section compensates for the relatively low expansion ratio of the rotary engine.

First claim

The invention claimed is:

1. A compound engine system comprising:
a Wankel engine having a rotor body mounted for eccentric revolutions within an internal cavity of a stator body to provide three rotating chambers of variable volume in the internal cavity, the internal cavity having an epitrochoid shape with two lobes, the rotor body having three apex portions separating the three rotating chambers, the volume of each of the three rotating chambers varying between a minimum volume and a maximum volume with a difference between the maximum and minimum volumes defining a displacement volume, a peripheral wall of the rotor body having a recess defined therein in each of the three rotating chambers, a volume of each recess being more than 5% of the displacement volume;
a compressor communicating with at least one inlet port of the Wankel engine for successive communication with each of the three rotating chambers; and
a turbine connected to at least one exhaust port of the Wankel engine for successive communication with each of the three rotating chambers.

2. The system as defined in claim 1 , wherein a volumetric compression ratio of the Wankel engine is lower than a volumetric expansion ratio of the Wankel engine.

3. The system as defined in claim 1 , wherein the volume of each recess is at least 6% of the displacement volume.

4. The system as defined in claim 2 , wherein the volume of each recess is at least 6% of the displacement volume.

5. The system as defined in claim 2 , wherein the volume of each recess is at most 15% of the displacement volume.

6. The system as defined in claim 2 , wherein the volume of each recess is at most 11% of the displacement volume.

7. The system as defined in claim 2 , wherein the volume of each recess is about 8% of the displacement volume.

8. The system as defined in claim 2 , wherein the volume of each recess is about 10% of the displacement volume.

9. The system as defined in claim 2 , wherein the volume of each recess is about 8 to 10% of the displacement volume.

10. The system as defined in claim 2 , wherein each recess is defined by a single pocket formed in the peripheral wall.

11. The system as defined in claim 1 , wherein the volume of each recess is at most 15% of the displacement volume.

12. The system as defined in claim 1 , wherein the volume of each recess is at most 11% of the displacement volume.

13. The system as defined in claim 1 , wherein the volume of each recess is about 8% of the displacement volume.

14. The system as defined in claim 1 , wherein the volume of each recess is about 10% of the displacement volume.

15. The system as defined in claim 1 , wherein the volume of each recess is about 8 to 10% of the displacement volume.

16. The system as defined in claim 1 , wherein each recess is defined by a single pocket formed in the peripheral wall.

Assignees

• Pratt & Whitney Canada

Inventors

• Julien Andre

Classifications

• F04C2240/20

  Rotors · CPC title

• F01C21/106

  with a radial surface, e.g. cam rings · CPC title

• Y10T29/49234

  Rotary or radial engine making · CPC title

• F02B55/14 Primary

  Shapes or constructions of combustion chambers · CPC title

• F04C29/0092

  Removing solid or liquid contaminants from the gas under pumping, e.g. by filtering or deposition; Purging; Scrubbing; Cleaning · CPC title