INTERNAL COMBUSTION ENGINE, VEHICLE, MARINE VESSEL, AND EXHAUSTING METHOD FOR INTERNAL COMBUSTION ENGINE

• US 20100180583A1
• Filed: 06/15/2009
• Published: 07/22/2010
• Est. Priority Date: 06/13/2008
• Status: Active Grant

• Current Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Original Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Inventors: Konakawa, Tsugunori, Takahashi, Yusuke
• Granted Patent: US 8,312,713 B2
• Time in Patent Office: Days
• US Class Current: 60/312
• CPC Class Codes: F01N 1/02 by using resonance
• CPC Class Codes: F01N 1/085 using a central core throttling gas passage
• CPC Class Codes: F01N 13/009 having two or more separate purifying devices arranged in series
• CPC Class Codes: F01N 13/08 Other arrangements or adaptations of exhaust conduits pipes, joints or supports therefor in general F16L; collecting or removing exhaust gases of vehicle engines in workshops B08B15/00, on highways E01C1/005
• CPC Class Codes: F01N 13/10 of exhaust manifolds with cooling jacket F01N3/046
• CPC Class Codes: F01N 2240/26 an exhaust gas reservoir, e.g. emission buffer
• CPC Class Codes: F01N 2470/30 Tubes with restrictions, i.e. venturi or the like, e.g. for sucking air or measuring mass flow
• CPC Class Codes: F01N 2490/14 Dead or resonance chambers connected to gas flow tube by relatively short side-tubes
• CPC Class Codes: F01N 3/02 for cooling, or for removing solid constituents of, exhaust by means of electric or electrostatic separators F01N3/01 ; mixing air with exhaust in tailpipes F01N13/082, F01N13/20
• CPC Class Codes: F01N 3/30 Arrangements for supply of additional air control, e.g. using by-passes or variable air pump drives, F01N3/22
• CPC Class Codes: F02B 27/04 in exhaust systems only, e.g. for sucking-off combustion gases
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An internal combustion engine includes a structure that increases the velocity of exhaust gas. The internal combustion engine includes a branch section arranged to branch a shock wave propagating at a higher velocity than exhaust gas and to guide the branched shock wave, and a reflecting section provided in the branch section. The reflecting section is arranged to reflect and return the shock wave back to an exhaust path and cause the shock wave to collide against the exhaust gas, thereby increasing the pressure of the exhaust gas. In accompaniment with the exhaust gas passing a divergent section of a convergent-divergent nozzle, a new shock wave propagating in a downstream direction in the exhaust path is generated, and the temperature and pressure of the exhaust gas are decreased.

Claims

1-7. -7. (canceled)

8. An internal combustion engine comprising:

a combustion chamber including an exhaust port;

an exhaust valve arranged to open and close the exhaust port; and

an exhaust device including;

an exhaust path arranged to guide exhaust gas discharged from the combustion chamber via the exhaust port;

a convergent section including a flow path cross-sectional area that is smaller at a downstream end thereof than at an upstream end thereof;

a divergent section provided downstream with respect to the convergent section and including a flow path cross-sectional area that is larger at a downstream end thereof than at an upstream end thereof; and

a branch section arranged to branch a shock wave, propagating in a downstream direction in the exhaust path at a higher velocity than the exhaust gas flowing into the exhaust path from the combustion chamber when the exhaust valve is opened, from a portion of the exhaust path which is upstream with respect to the divergent section, and to propagate the branched shock wave back to the exhaust path;

wherein

the divergent section is connected to the combustion chamber provided upstream with respect to the divergent section;

the exhaust gas flowing into the exhaust path from the combustion chamber is caused to pass the convergent section and to collide against the shock wave which has propagated in the branch section, between the branch section and the divergent section, so as to increase the pressure of the exhaust gas in the convergent section; and

the exhaust gas is caused to pass the divergent section to generate a new shock wave, and a negative pressure is generated upstream with respect to the divergent section in the exhaust path by the generated new shock wave.

10. The internal combustion engine according to claim 8, wherein the exhaust path further includes a portion including a constant flow path cross-sectional area between the convergent section and the divergent section.

13. A vehicle comprising the internal combustion engine according to claim 8.

14. A marine vessel comprising the internal combustion engine according to claim 8.

9. An internal combustion engine comprising:

a combustion chamber including an exhaust port;

an exhaust valve arranged to open or close the exhaust port; and

an exhaust device including;

an exhaust path arranged to guide exhaust gas discharged from the combustion chamber via the exhaust port;

a convergent section including a flow path cross-sectional area that is smaller at a downstream end thereof than at an upstream end thereof;

a divergent section provided downstream with respect to the convergent section and including a flow path cross-sectional area that is larger at a downstream end thereof than at an upstream end thereof; and

a branch section branched from a portion of the exhaust path which is upstream with respect to the divergent section and including a reflecting section arranged to reflect a shock wave;

wherein

the divergent section is connected to the combustion chamber provided upstream with respect to the divergent section;

where a velocity of the exhaust gas discharged from the combustion chamber when the exhaust valve is opened is Ve and a propagation velocity of the shock wave propagating in the exhaust path is Vs, a distance Le between the exhaust port and an entrance of the branch section and a distance Ls between the entrance of the branch section and the reflecting section fulfill a relationship of;

Le/Ve≦

(Le+2Ls)/Vs; and

where a time from when the exhaust port is opened until the exhaust port is closed is tv, a distance Ld between the entrance of the branch section and the divergent section fulfills a relationship of;

(Le+2Ls+Ld)/Vs≦

tv+(Le+Ld)/Ve.

11. The internal combustion engine according to claim 9, wherein the exhaust path further includes a portion including a constant flow path cross-sectional area between the convergent section and the divergent section.

12. An exhausting method for an internal combustion engine, the method comprising the steps of:

combusting fuel in a combustion chamber;

opening an exhaust port of the combustion chamber to discharge exhaust gas from the combustion chamber to an exhaust path and to generate a shock wave propagating in the exhaust path at a higher velocity than the exhaust gas;

branching at least a portion of the shock wave from the exhaust path and propagating the branched shock wave back to the exhaust path to cause the shock wave to collide against the exhaust gas so as to increase the pressure of the exhaust gas;

causing the exhaust gas to flow into a portion of the exhaust path having a smaller flow path cross-sectional area in a downstream section thereof than in an upstream section thereof so as to increase the pressure of the exhaust gas; and

causing the exhaust gas to flow into a portion of the exhaust path having a larger flow path cross-sectional area in a downstream section thereof than in an upstream section thereof so as to generate a new shock wave propagating in a downstream direction in the exhaust path to generate a region of a negative pressure in the exhaust path.

15. A method of operating an internal combustion engine, the method comprising the steps of:

operating the internal combustion engine; and

exhausting gas from the internal combustion engine including the steps of;

combusting fuel in a combustion chamber;

opening an exhaust port of the combustion chamber to discharge exhaust gas from the combustion chamber to an exhaust path and to generate a shock wave propagating in the exhaust path at a higher velocity than the exhaust gas;

branching at least a portion of the shock wave from the exhaust path and propagating the branched shock wave back to the exhaust path to cause the shock wave to collide against the exhaust gas so as to increase the pressure of the exhaust gas;

causing the exhaust gas to flow into a portion of the exhaust path having a smaller flow path cross-sectional area in a downstream section thereof than in an upstream section thereof so as to increase the pressure of the exhaust gas; and

causing the exhaust gas to flow into a portion of the exhaust path having a larger flow path cross-sectional area in a downstream section thereof than in an upstream section thereof so as to generate a new shock wave propagating in a downstream direction in the exhaust path to generate a region of a negative pressure in the exhaust path.