Patent ID: 12196151

IN THE FIGURE

1bottom face;2main arc face;3first arc ridge;4first inclined face;5transition arc;6second arc ridge;7second inclined face;8throat transition face;9top face; and10fuel injector.

DETAILED DESCRIPTION OF EMBODIMENTS

The technical solutions of the present application are clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the present application, not all of them. All other embodiments obtained based on the embodiments in the present application without creative efforts by those skilled in the art fall are within the protection scope of the present application.

In the description of the present application, it should be noted that, orientations or positional relationships indicated by terms such as “center”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “inside” and “outside” are based on the orientations or position relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that devices or elements referred to must have specific orientations, or must be constructed and operated in specific orientations, and thus should not be understood as limitations to the present application. In addition, terms “first” and “second” are only used for description, and should not be understood as indicating or implying relative importance. The terms “first position” and “second position” represent two different positions. Moreover, the first feature being “on”, “above” and “over” the second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicate that the first feature is horizontally higher than the second feature. The first feature being “below”, “under” and “beneath” the second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicate that the first feature is horizontally lower than the second feature.

In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, terms “mount”, “connect to” and “connect” should be understood in a broad sense, for example, may be a fixed connection, a detachable connection, or an integrated connections; may be a mechanical connection or an electric connection; may be a direct connection, or an indirect connection through an intermediary, and may be an internal connection of two elements. For those skilled in the art, the specific meanings of the terms in the present application can be understood based on specific situations.

The embodiments of the present application are described in detail below, examples of the embodiments are shown in the accompanying drawings, and same or similar reference signs represent same or similar elements or elements with same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary, and are intended to explain the present application, and should not be understood as limitations to the present application.

As shown inFIG.1, a combustion system is provided according to the embodiment. The combustion system includes a cylinder, a piston, a fuel injector10and a control system.

The cylinder has a cylinder chamber, the piston is slidably arranged in the cylinder chamber of the cylinder, and a combustion chamber communicated to the cylinder chamber is provided on top of the piston. The piston is driven by a crankshaft and so on, and can reciprocate in the cylinder.

A side wall of the combustion chamber is formed with a first arc ridge3and a second arc ridge6that are spaced apart from each other, and the first arc ridge3and the second arc ridge6protrude into the combustion chamber. Specifically, the structure of the combustion chamber is shown inFIG.1, the combustion chamber is roughly a w-shaped combustion chamber.FIG.1only shows a half of the cross-section of the combustion chamber, which has a top face9, a conical bottom face1, and an annular side wall connecting the top face9and the bottom face1. The side wall specifically includes a main arc face2, a first arc ridge3, a first inclined face4, a transition arc5, a second arc ridge6, a second inclined face7, and a throat transition face8arranged sequentially from bottom to top. The bottom face1, the main arc face2, the first arc ridge3, the first inclined face4, the transition arc5, the second arc ridge6, the second inclined face7, the throat transition face8, and top face9are tangentially connected in sequence. The main arc face2is concave inwardly, the first arc ridge3is closer to a center of the combustion chamber than the second arc ridge6, and the second arc ridge6is closer to a top face of the combustion chamber than the first arc ridge3. In the embodiment, the first arc ridge3is closer to the middle of the combustion chamber than the second arc ridge6along a depth direction of the combustion chamber. Preferably, the first arc ridge3is formed as a first arc2viewed in a vertical section of the combustion chamber, the second arc ridge6is formed as a second arc viewed in the vertical section of the combustion chamber, a radius of the first arc2is R1, a radius of the second arc is R2, and R1is equal to 2R2to 3R2. In this way, a fuel-receiving area of the first arc ridge3is relatively large and centered, which facilitates the back splash of the fuel to various positions in the combustion chamber, so that the fuel can fully mix with air at the top, the middle and the bottom of the combustion chamber.

The fuel injector10is used to inject fuel into the combustion chamber, and the control system is used to control the velocity of the fuel injected by the fuel injector10. The control system can control the fuel injector10to inject fuel to the first arc ridge3at a velocity not lower than a set velocity, and can control the fuel injector10to inject fuel to the second arc ridge6at a velocity not lower than the set velocity. The fuel injector10is supplied with the fuel through an oil pump, and the control system may include a controller and a regulating valve. The regulating valve is arranged in a connecting pipeline between the oil pump and the fuel injector10, and the regulating valve is connected to the controller. The controller can adjust the flow rate of the passing fuel through the regulating valve, thereby the velocity of the fuel injected by the fuel injector10is controlled. It can be understood that, the fuel injector10is performing a main injection when the fuel injector10injects fuel at a velocity not lower than the set velocity, and the fuel injector10is performing pre-injection when the fuel is injected at a velocity lower than the set velocity. The combustion chamber is adopted with two arc ridges, and the fuel is injected to the two arc ridges through the fuel injector, which can ensure that the amount of the fuel shared by each of the arc ridges is reduced, avoid excessive accumulation of the fuel at a single arc ridge, facilitate the improvement of the velocity field of a jet hitting a wall at the end of the oil beam by the arc ridge, and is also conducive to the full mixing of fuel droplets and air.

A method for controlling a combustion system is also provided according to the embodiment, and the method for controlling a combustion system may be implemented through the combustion system described above. Specifically, the method for controlling a combustion system is implemented as follows: the fuel injector10performs a first main injection and a second main injection at intervals, the fuel injector10injects the fuel to the first arc ridge3during the first main injection, and the fuel can splash back. The fuel injector10injects the fuel to the second arc ridge6during the second main injection, and the fuel can splash back. Velocities of the fuel injected during the first main injection and the second main injection are not lower than the set velocity. The two arc ridges guide and distribute the fuel of the two main injections, which is beneficial to strengthen the distribution of oil and gas in the cylinder, improves the utilization rate of air in the cylinder chamber, and improves the combustion efficiency, thereby improving the thermal efficiency of the engine.

In other embodiments, three or more arc ridges of the combustion chamber may be provided. Taking three arc ridges as an example, the combustion chamber may also have a third arc ridge that is spaced apart from the first arc ridge3and the second arc ridge6, and the third arc ridge protrudes outwardly towards the combustion chamber. The fuel injector10is controlled to perform three main injections during the movement of the piston, and oil beams of the three main injections fall onto the three arc ridges respectively, which further enhances the effect of oil-gas mixing.

Optionally, the piston moves upward in the cylinder and can compress gas in the cylinder chamber when the fuel injector10performs the first main injection. The piston moves downward in the cylinder when the fuel injector10performs the second main injection. In this way, the symmetry of the upward and downward movement of the piston can be fully used to refine the landing positions of the fuel and fully utilize the diversion effect and back splashing effect of the two arc ridges. Preferably, a vertical distance between the center of the first arc ridge3and the center of the second arc ridge6is H1, and a displacement between a position of the piston when the fuel injector10performs the first main injection and a position of the piston when the fuel injector10performs the second main injection is H2, and H1is equal to H2. In this way, the orientation of a fuel injection hole of the fuel injector10is not required to be adjusted, and the fuel can be accurately injected to the two arc ridges during the up and down movement of the piston.

Optionally, during a period between the first main injection and the second main injection performed by the fuel injector10, the fuel injector10continuously injects the fuel, and a velocity of the fuel injected by the fuel injector10is lower than the set velocity. In this way, the uniformity of oil-gas mixing in the cylinder chamber is further improved.

Optionally, as shown inFIG.1, when the fuel injector10performs the first main injection, the fuel injection hole of the fuel injector10faces toward the center of the first arc ridge3, and a distance between the fuel injection hole of the fuel injector10and the center of the first arc ridge3is L1. A velocity of the fuel injected from the fuel injection hole of the fuel injector10is V1, and an ignition delay period of the fuel injected during the first main injection is t1, and t1=L1/V1. In this way, time tiafter the fuel is injected from the fuel injector10, the fuel contacts the first arc ridge3, and then the fuel enters a rapid combustion period after splashing, which does not affect the subsequent splashing effect of the fuel on the first arc ridge3. The ignition delay period of the fuel may be regulated by temperature, oil quality, and so on.

Optionally, when the fuel injector10performs the second main injection, the fuel injection hole of the fuel injector10faces towards the center of the second arc ridge6, and a distance between the fuel injection hole of the fuel injector10and the second arc ridge6is L2. A velocity of the fuel injected from the fuel injection hole of the fuel injector10is V2, an ignition delay period of the fuel injected during the second main injection is t2, and t2=L2/V2. In this way, time t2after the fuel is injected from the fuel injector10, the fuel contacts the second arc ridge6, and then the fuel enters a rapid combustion period after splashing, which does not affect the subsequent splashing effect of the fuel on the second arc ridge6.

An engine is also provided according to the embodiment, and includes the combustion system described above.

Apparently, the embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementations of the present application. For those skilled in the art, other variations or changes can be made based on the above description. It is not necessary and impossible to exhaustively list all implementations herein. Any modifications, equivalent replacements and improvements made within the spirit and the principles of the present application shall be included within the protection scope of the present application.