CN101446225A

CN101446225A - Combustion system applied in direct injection diesel

Info

Publication number: CN101446225A
Application number: CNA2008101543635A
Authority: CN
Inventors: 郑尊清; 尧命发; 陈征
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2008-12-23
Filing date: 2008-12-23
Publication date: 2009-06-03

Abstract

The invention discloses a combustion system applied in a direct injection diesel, comprising a W-shaped combustion chamber and an oil atomizer that is used for injecting high-pressure fuel oil into the combustion chamber. A plurality of arc concave pits which have the same number with oil beams of the oil atomizer and correspond to the injecting direction thereof are uniformly arranged on the inner wall of the W-shaped combustion chamber along the peripheral direction, the lower edge of every arc concave pit is connected with the inner wall of the combustion chamber in a first change structure way by the transition of small round corners, and the two side edges of every arc concave pit are connected with the intersection of the inner wall surfaces of the combustion chamber in a second change structure by the transition of the small round corners. By adopting the structure of the invention, separation between the fuel oil and the wall surface of the combustion chamber is realized in two directions, therefore, the fuel oil precipitated on the wall surface of the combustion chamber is greatly reduced, meanwhile, two spraying jets expand the range for the fuel oil to be mixed in the combustion chamber and the air is more fully utilized, thus being beneficial to reducing harmful emission.

Description

A kind of combustion system that is applied to diesel engine with direct injection

Technical field

The present invention relates to a kind of combustion system,, the invention particularly relates to a kind of combustion system that is applied to diesel engine with direct injection for engine mixed gas forms and combustion field.

Background technique

Energy saving and the ambilateral demand of protection environment impel engine technology to develop to the direction of high-efficiency cleaning burning.Particulate and NOx are most important two kinds of noxious emissions of diesel engine, and exist a kind of this that long relations (Trade-off) that disappear between two kinds of effulents, promptly reduce the rising that a kind of measure of effulent often brings another kind of effulent.Traditional combustion system of diesel engine, the nonuniformity of mixed gas is bigger in spray mixing process, the zone that has more mixed gas overrich easily, cause more particulate to generate, and the Trade-off between particulate and NOx relation is difficult to improve, and this just makes and reduces by two kinds of effulents simultaneously and become a technical barrier.Recent studies show that, motor can be avoided the generation of particulate under less than 2 situation at mixture equivalence, this explanation is strengthened fuel oil and Air mixing and is had critical effect aspect the discharging improving, and this is just for reducing harmful emission of diesel engine, realizing that high-efficiency cleaning burns a direction is provided.

Summary of the invention

The objective of the invention is to overcome the prior art deficiency, a kind of quality of mixing gas mixture that can improve diesel engine is provided, strengthen fuel oil and Air mixing, realize a kind of combustion system that is applied to diesel engine with direct injection of the efficient and low emission of motor.

A kind of combustion system that is applied to diesel engine with direct injection of the present invention, it comprises ω shape firing chamber, the oil sprayer that is used for inject high pressure fuel oil in the firing chamber, its circumferencial direction of inwall upper edge, described ω shape firing chamber be provided with uniformly equate with the oil bundle quantity of oil sprayer and with the corresponding a plurality of arc pits of its injection direction, the lower limb of described each arc pit forms first mutation structure with the firing chamber inwall by little round-corner transition and links to each other, and the both sides of the edge of described each arc pit form second mutation structure with internal face intersection, described firing chamber by little round-corner transition and link to each other.

Adopt arc bowl configurations of the present invention on both direction, to have guide functions, fuel oil is diffusion rapidly on guide face, on both direction, realize peeling off of fuel oil and combustion chamber wall surface, make that on the one hand the fuel oil that is deposited on the combustion chamber wall surface significantly reduces, while secondary spray stream mixes fuel oil in the firing chamber scope is bigger, the utilization of air is more abundant, helps reducing noxious emission.And described bowl configurations can be processed on traditional ω shape firing chamber and obtain, and realizes easily on the technology, is convenient to product and uses.

Description of drawings

Fig. 1 is a kind of plan view that is applied to the combustion system of diesel engine with direct injection of the present invention;

Fig. 2 is the A place enlarged view of combustion system shown in Figure 1;

Fig. 3 is the plan view of combustion system shown in Figure 1;

Fig. 4 is the B place enlarged view of combustion system shown in Figure 3;

Fig. 5 is the oil spout view of combustion system shown in Figure 1;

Fig. 6 is the plan view of combustion system shown in Figure 5.

Embodiment

Below in conjunction with the drawings and specific embodiments the present invention is done to describe in detail.

A kind of combustion system that is applied to diesel engine with direct injection of the present invention, it comprises ω shape firing chamber 1, the oil sprayer 2 that is used for inject high pressure fuel oil in the firing chamber, its circumferencial direction of inwall upper edge, described ω shape firing chamber be provided with uniformly equate with the oil bundle quantity of oil sprayer and with the corresponding a plurality of arc pits of its injection direction, the lower limb of described each arc pit forms first mutation structure 5 with the firing chamber inwall by little round-corner transition and links to each other, and the both sides of the edge of described each arc pit form second mutation structure 6 with internal face intersection, described firing chamber by little round-corner transition and link to each other.The sudden change that the lower limb of described each arc pit and both sides of the edge and combustion chamber wall surface jointing place form is big more, play to peel off effect good more, if but be wedge angle, then heat load weak effect at high temperature so described little fillet is the fillet that approaches wedge angle, could form bigger sudden change like this, play and better peel off effect, fillet is big more, crosses and gets over gently, and the effect of peeling off can weaken.The intersection, bottom of the arc surface 9 of cambered surface 8 tops and arc pit has formed first mutation structure 5 by little round-corner transition among the described partial enlarged drawing A, and the intersection of the arc surface 11 of the arc surface 10 of firing chamber internal face and described arc pit has formed second mutation structure 6 by little round-corner transition among the partial enlarged drawing B.

Shown in Fig. 1-6,1 inwall has 8 arc bowl configurations (is the example explanation with 8) in the firing chamber, each bowl configurations has the water conservancy diversion cambered

surface

3 and 4 of both direction, it is first and

second mutation structure

5 and 6 that the edge of water conservancy diversion cambered surface and combustion chamber wall surface jointing place have the fillet of leading respectively, the quantity of oil sprayer oil bundle 7 is 8 bundles (identical with the quantity of pit), and the direction that the oil bundle sprays is the position of pit.The fuel oil oil bundle of high-pressure injection has bigger momentum, part bounce-back after groove position is hit wall, another part is expanded rapidly along smooth water conservancy diversion cambered

surface

3 and 4, behind the position that expands to first and

second mutation structure

5 and 6, thereby peel off with wall and to have formed the secondary spray stream, shown in Fig. 5-6.This makes that fuel oil distributes in the whole bags more even, and the air utilization is more abundant, helps reducing the Trade-off relation that particulate generated and improved particulate and NOx, realizes the efficient low-discharging burning.

Claims

1. combustion system that is applied to diesel engine with direct injection, it comprises ω shape firing chamber, the oil sprayer that is used for inject high pressure fuel oil in the firing chamber, it is characterized in that: its circumferencial direction of inwall upper edge, described ω shape firing chamber be provided with uniformly equate with the oil bundle quantity of oil sprayer and with the corresponding a plurality of arc pits of its injection direction, the lower limb of described each arc pit forms first mutation structure with the firing chamber inwall by little round-corner transition and links to each other, and the both sides of the edge of described each arc pit form second mutation structure with internal face intersection, described firing chamber by little round-corner transition and link to each other.