Supercharged direct injection engine cylinder cover and cooling water jacket structure thereof
Technical Field
The invention relates to a cooling system of an automobile engine, in particular to a cylinder cover of a supercharged direct injection engine and a cooling water jacket structure thereof.
Background
The new generation of engine generally adopts the technical routes of supercharging direct injection, miniaturization, integration of an exhaust manifold, variable compression ratio and the like, so that very high boost power can be achieved, and the economy and the emission performance are improved while the dynamic property is ensured. However, higher power-per-liter increases the combustion pressure of the cylinder and causes greater thermal load around the combustion cylinder and in the area of the integrated exhaust manifold, placing greater demands on the cooling jacket structure of the cylinder head.
In order to achieve better cooling effect, the cylinder cover water jacket gradually adopts a double-layer water jacket structure at present, an upper layer and a lower layer of the double-layer water jacket wrap an exhaust manifold and are communicated with each other on the side of the exhaust manifold, and cylinder body water jacket cooling water firstly flows into the exhaust side of the cylinder cover water jacket and then flows out from the air inlet side of the cylinder cover water jacket. The double-layer water jacket structure enables the circulation path of cooling water to be lengthened, the flow resistance of the cooling water is increased, the temperature of the cooling water is greatly increased after the cooling water reaches the exhaust manifold region through a longer flow passage, and the cooling effect is affected. In addition, current double-layered water jacket structures are more focused on cooling the exhaust manifold area, while the temperature field in the area around the cylinder head combustion chamber of high compression ratio high performance engines is higher, while current double-layered water jacket structures lack further effective cooling around the cylinder head combustion chamber.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a cylinder cover cooling water jacket structure which can effectively reduce the flow resistance of a cylinder cover cooling water jacket and increase the cooling effect of a combustion cylinder for a supercharged direct injection engine with a high compression ratio.
The invention also provides a cylinder cover structure with the cylinder cover cooling water jacket.
In order to achieve the above object, the present invention provides a cylinder head cooling water jacket structure of a supercharged direct-injection engine, including an upper water jacket and a lower water jacket respectively located at the upper and lower sides of an exhaust manifold, the upper water jacket extending obliquely downward from the upper side of the exhaust manifold to an intake side, the lower water jacket extending downward from the lower side of the exhaust manifold to an exhaust side, characterized in that: the combustion chamber water jacket is positioned on the outer side of the combustion chamber, the combustion chamber water jacket is positioned in the cylinder wall between the combustion chambers, and the combustion chamber top water jacket is positioned on the exhaust side of the top of the combustion chamber; and water inlets of the combustion cylinder outer side water jacket, the combustion chamber top water jacket and the combustion cylinder partition wall water jacket are positioned on the exhaust side, and water outlets of the combustion cylinder outer side water jacket, the combustion chamber top water jacket and the combustion cylinder partition wall water jacket are positioned on the air inlet side.
Further, the cylinder head cooling water jacket structure is located at the upper end of the cylinder block water jacket, and the cylinder block water jacket comprises a cylinder block exhaust side water jacket located at the exhaust side and a cylinder block intake side water jacket located at the intake side.
Further, the upper-layer water jacket is communicated with the cylinder body air inlet side water jacket through an upper-layer water jacket water outlet; and the lower-layer water jacket is communicated with the cylinder exhaust side water jacket through a lower-layer water jacket water inlet.
Further, the block exhaust side water jacket and the block intake side water jacket are separated by a first partition plate and a second partition plate, respectively.
Further, the water inlets of the combustion cylinder outer side water jacket, the combustion chamber top water jacket and the combustion cylinder partition wall water jacket are communicated with the cylinder body exhaust side water jacket, the water outlets of the combustion cylinder outer side water jacket and the combustion chamber top water jacket are communicated with the upper layer water jacket, and the water outlet of the combustion cylinder partition wall water jacket is communicated with the cylinder body air inlet side water jacket.
Furthermore, the upper-layer water jacket and the lower-layer water jacket are communicated through a bowl-shaped plug hole, and the bowl-shaped plug hole is located on the end face where the exhaust manifold is located.
Furthermore, a water jacket air outlet with an upward opening is formed in the top of the exhaust side of the upper-layer water jacket.
The cylinder head cooling water jacket structure of the supercharged direct injection engine provided by the invention has the following beneficial effects:
1. the cooling effect of the peripheral area of the combustion chamber of the cylinder cover is enhanced. On the basis of the existing double-layer water jacket structure, a combustion cylinder partition wall water jacket, a combustion cylinder outer side water jacket and a combustion chamber top water jacket are respectively arranged in the area around a combustion chamber, and a cylinder wall between the combustion chambers, the area outside the combustion cylinder and the area of a combustion chamber exhaust valve seat are sequentially cooled.
2. Reducing the cooling water flow resistance. One end of the outer water jacket of the combustion cylinder and one end of the top water jacket of the combustion chamber are communicated with the exhaust side water jacket of the cylinder body, the other end of the outer water jacket of the combustion cylinder and the top water jacket of the combustion chamber are directly communicated with the upper layer water jacket, and two ends of the partition wall water jacket of the combustion cylinder are directly communicated with the exhaust side and the air inlet side of the water jacket of the cylinder body respectively, so that the circulation length of cooling water is effectively reduced.
The cylinder head cooling water jacket structure of the supercharged direct-injection engine provided by the invention comprises a cylinder head cooling water jacket arranged in the cylinder head, wherein the cylinder head cooling water jacket is any one of the cylinder head cooling water jacket structures of the supercharged direct-injection engine.
Drawings
Fig. 1 is a front view of a cylinder head water jacket structure.
Fig. 2 is a bottom view of a cylinder head water jacket structure.
Fig. 3 is a bottom view of the cylinder head structure.
Fig. 4 is a sectional view taken along the line a in fig. 3.
Fig. 5 is a sectional view taken along line B in fig. 3.
FIG. 6 is a schematic view of the connection between the cylinder head water jacket and the cylinder body water jacket.
Fig. 7 is a sectional view of a cylinder head water jacket.
Fig. 8 is a rear view of the head jacket.
Fig. 9 is a cross-sectional view taken along line C of the bowl-shaped receptacle of fig. 8.
The components in the figures are numbered as follows:
the water jacket comprises a cylinder cover upper-layer water jacket 1, an upper-layer water jacket water outlet 1.1, a water jacket air outlet 1.2, a cylinder cover lower-layer water jacket 2, a lower-layer water jacket water inlet 2.1, a combustion cylinder outer-side water jacket 3, a combustion chamber top water jacket 4, a combustion cylinder partition wall water jacket 5, an exhaust manifold 6, a bowl-shaped plug hole 7, a combustion chamber 8, an exhaust valve seat 9, an intake valve seat 10, a cylinder water jacket 11, a cylinder water jacket water inlet 11.1, a cylinder water jacket water outlet 11.2, a cylinder exhaust-side water jacket 11.3, a cylinder intake-side water jacket 11.4, a first partition plate 15.
Detailed Description
The invention will be described in more detail below with reference to the accompanying drawings, which are included to provide a more clear understanding of the invention, but are not intended to limit the invention.
As shown in fig. 1 to 9, a cylinder head cooling water jacket structure of a supercharged direct-injection engine comprises an upper layer water jacket 1 and a lower layer water jacket 2 which are respectively positioned at the upper side and the lower side of an exhaust manifold 6, wherein the exhaust manifold 6 is wrapped by the upper layer water jacket 1 and the lower layer water jacket 2, the upper layer water jacket 1 extends from the upper side of the exhaust manifold 6 to the air inlet side in an inclined manner, the lower layer water jacket 2 extends from the lower side of the exhaust manifold 6 to the air outlet side in a inclined manner, the upper layer water jacket 1 is communicated with an air inlet side water jacket 11.4 of a cylinder body through an upper layer water jacket water outlet 1.1, the lower layer water jacket 2 is communicated with an air outlet side water jacket 11.3 of the cylinder body through a lower layer; the water inlet 2.1 of the lower water jacket is positioned on the exhaust side of the combustion chamber 8; an exhaust valve seat 9 is arranged on the exhaust side of the combustion chamber 8, and an intake valve seat 10 is arranged on the intake side of the combustion chamber 8; the water jacket 4 is located between the exhaust valve seats 9 at the top of the combustion chamber 8. The combustion engine further comprises a combustion cylinder partition wall water jacket 5, the combustion cylinder partition wall water jacket 5 is positioned in the cylinder wall between the combustion chambers 8, the combustion cylinder partition wall water jacket 5 is V-shaped, one end of the combustion cylinder partition wall water jacket 5 is communicated with the cylinder body exhaust side water jacket 11.3, and the other end of the combustion cylinder partition wall water jacket is communicated with the cylinder body intake side water jacket 11.4; a combustion cylinder outer side water jacket 3 is arranged in the outer side cylinder wall of the combustion chamber 8, a combustion chamber top water jacket 4 is arranged at one end, close to the exhaust side, of the combustion chamber 8, one end of each of the combustion cylinder outer side water jacket 3 and the combustion chamber top water jacket 4 is communicated with the cylinder body exhaust side water jacket 11.3, and the other end of each of the combustion cylinder outer side water jacket 3 and the combustion chamber top water jacket 4 is communicated with the upper layer water.
In the technical scheme, the upper-layer water jacket 1 is communicated with the lower-layer water jacket 2 through the bowl-shaped plug hole 7, the bowl-shaped plug hole 7 is positioned on the end face where the exhaust manifold 6 is positioned, and the top of the exhaust side of the upper-layer water jacket 1 is provided with a water jacket air outlet 1.2 with an upward opening. Thus, the bowl-shaped plug hole 7 is communicated with the upper-layer water jacket 1 and the lower-layer water jacket 2 at the same time, and the bowl-shaped plug hole 7 is sealed by the bowl-shaped plug, so that the cooling water of the lower-layer water jacket is prevented from forming a closed loop; the water jacket air outlet 1.2 is connected with a warm air return pipe, and air in the cooling water can be discharged from the water jacket air outlet 1.2.
In the above technical solution, the block water jacket 11 includes a block exhaust side water jacket 11.3 and a block intake side water jacket 11.4, and the block exhaust side water jacket 11.3 and the block intake side water jacket 11.4 are separated by a first partition plate 15 and a second partition plate 16, respectively. The cooling water firstly enters the cylinder exhaust side water jacket 11.3 from the cylinder water jacket inlet 11.1, and the cooling water in the cylinder exhaust side water jacket 11.3 firstly enters the cylinder head water jacket due to the blocking effect of the first partition plate 15 and the second partition plate 16. Wherein, the first part of cooling water enters the lower layer water jacket 2 through the lower layer water jacket water inlet 2.1, the lower layer water jacket 2 mainly cools the lower end of the cylinder cover and the lower end of the exhaust manifold 6, the cooling water in the lower layer water jacket 2 completely flows into the upper layer water jacket 1 through the communication part of the bowl-shaped plug hole 7, and the upper layer water jacket 1 mainly cools the partition wall of the combustion chamber 8, the upper part of the cylinder cover and the upper part of the exhaust manifold 6; the second part of cooling water flows into the upper layer water jacket 1 through the combustion cylinder outer side water jacket 3 and the combustion chamber top water jacket 4, the combustion cylinder outer side water jacket 3 and the combustion chamber top water jacket 4 respectively cool the outer side of the combustion cylinder and the area of the combustion chamber 8 close to the exhaust valve seat 9, and the cooling water of the upper layer water jacket 1 finally flows into the cylinder body air inlet side water jacket 11.4 through the upper layer water jacket water outlet 1.1; the remaining part of the cooling water passes through the wall between the combustion chambers 8 through the inter-combustion-cylinder-wall water jacket 5, and then flows directly into the block-intake-side water jacket 11.4, and the inter-combustion-cylinder-wall water jacket 5 cools the wall region between the combustion cylinders. And finally, the cylinder body air inlet side water jacket 11.4 completely flows out of the cylinder body water jacket 11 through the cylinder body water jacket water outlet.
The compression ratio of the new generation of supercharged direct injection engine with high compression ratio can reach 15.5-16.5, the combustion pressure is increased while the boost power is improved, and the temperature around the combustion chamber is higher than that of the traditional supercharged direct injection engine during working. As shown in fig. 1 to 6 as an example, in a double-layer water jacket structure of a conventional three-cylinder engine, the highest temperature of the surface of a cylinder head combustion chamber 8 is 360 to 370 ℃, the highest temperature of a cylinder head exhaust valve seat 9 region is 370 to 380 ℃, and the highest temperature of a cylinder head exhaust manifold 6 is 335 to 340 ℃, so that the cylinder head has a large risk of thermal fatigue failure, and the cooling requirement of the region around the combustion chamber 8 is higher. The utility model discloses to this kind of apparent characteristic of high compression ratio engine, in the cylinder wall between combustion cylinder, combustion cylinder outside and combustion chamber 8 have set up combustion cylinder outside water jacket 3, combustion cylinder dividing wall water jacket 5 and combustion chamber top water jacket 4 respectively by the top region of exhaust valve seat 9, cool off combustion chamber region all around specially, 8 surperficial highest temperatures of cylinder cap combustion chamber after the cooling are 290 ℃ -295 ℃, cylinder cap exhaust valve seat 9 highest temperatures are 305 ℃ -310 ℃, cylinder cap exhaust manifold 6 highest temperatures are 270 ℃ -275 ℃; the cooling device can reduce the peripheral area of the combustion chamber in the cylinder cover by 60-80 ℃, and well meets the cooling requirement of the cylinder cover of the engine with high compression ratio.
The embodiment of the invention also provides a cylinder head structure of a supercharged direct-injection engine, which comprises a cooling water jacket arranged in the cylinder head, wherein the cooling water jacket is the cylinder head cooling water jacket structure of the supercharged direct-injection engine provided by any one of the above embodiments.
The cylinder cover structure of the supercharged direct-injection engine comprises an upper-layer water jacket and a lower-layer water jacket, and is used for cooling the upper side and the lower side of an exhaust manifold and a cylinder cover.