CN115126620A

CN115126620A - Liquid cooling type internal combustion engine

Info

Publication number: CN115126620A
Application number: CN202210290665.5A
Authority: CN
Inventors: S·施托克尔-赖歇尔; J·盖尔特
Original assignee: AVL List GmbH
Current assignee: AVL List GmbH
Priority date: 2021-03-24
Filing date: 2022-03-23
Publication date: 2022-09-30
Also published as: AT524566B1; DE102022106749A1; AT524566A4

Abstract

The invention relates to a liquid-cooled internal combustion engine (1), in particular a large engine, comprising a cylinder head (2) with a cylinder head cooling jacket (3) and a cylinder block (4) with a cylinder block cooling jacket (5), which have the concept of cooling from the top down, wherein at least one cylinder (6) is arranged in the cylinder block (4), wherein the cylinder head cooling jacket (3) comprises a cylinder head inlet channel (7) and a cylinder head outlet channel (8), and wherein the cylinder block cooling jacket (5) comprises a cylinder block inlet channel (9) and a cylinder block outlet channel (10), wherein a connecting channel (11) is arranged between the cylinder head cooling jacket (3) and the cylinder block cooling jacket (5), wherein a control device (12) is arranged in the connecting channel, so that the cylinder head cooling jacket (3) and the cylinder block cooling jacket (5) are optionally in flow connection.

Description

Liquid cooling type internal combustion engine

Technical Field

The invention relates to a liquid-cooled internal combustion engine, in particular a large engine, comprising a cylinder head with a cylinder head cooling jacket and a cylinder block with a cylinder block cooling jacket, which have the concept of cooling from the top down, wherein at least one cylinder is arranged in the cylinder block, wherein the cylinder head cooling jacket comprises a cylinder head inlet channel and a cylinder head outlet channel, and the cylinder block cooling jacket comprises a cylinder block inlet channel and a cylinder block outlet channel.

The invention also relates to a method for cooling an internal combustion engine.

Background

Liquid-cooled internal combustion engines are known from the prior art.

From AT 515143B 1 and AT 503182 a2, respectively, a liquid-cooled internal combustion engine with a cylinder head and a cylinder block is known, wherein the cylinder head has two overlapping sub-cooling chambers, which are flowed through according to the so-called top-down cooling concept. The two sub-cooling chambers are separated from each other by an intermediate layer and are connected in flow communication in the region of the central ejector sleeve by at least one overflow. The coolant is supplied through an inlet channel in the cylinder block, flows through the cooling chambers in the cylinder block surrounding the cylinder, and is directly supplied to the sub-cooling chambers on the upper side of the cylinder head via the overflow channel and the supply channel in the fire power layer. The cylinder head is thereby flowed through from top to bottom, the coolant being first fed into the upper partial cooling chamber and, after flowing through the upper partial cooling chamber, flowing via the at least one overflow into the lower partial cooling chamber, the coolant being guided in this case via the radial cooling ducts radially from the inside to the outside in the region of the valve bridge and finally leaving the cylinder head again via the laterally arranged drainage ducts.

AT 522272 a1 also shows a liquid-cooled internal combustion engine, in which case AT least one cooling jacket is provided for the cylinder head and the cylinder block, respectively. The flow through the cylinder head cooling jacket can be regulated by at least one valve.

A disadvantage of the known solution is that the cooling jacket solution implemented can only react to different load situations to a limited extent.

Disclosure of Invention

The present invention derives from this. The aim of the invention is to be able to cool an internal combustion engine efficiently under all varying thermal loads.

This object is achieved according to the invention in that, in an internal combustion engine of the type mentioned in the introduction, a connecting channel is provided between the head cooling jacket and the block cooling jacket, wherein a control device is provided in the connecting channel, so that the head cooling jacket and the block cooling jacket are possibly connected in flow communication.

The advantage thereby obtained is in particular that, depending on the cooling requirements, the cylinder head and the cylinder block can be flowed through separately from each other by the cooling liquid or the cooling liquid can be flowed through the cylinder head and the cylinder block in a common cooling circuit. In the internal combustion engine according to the invention, therefore, depending on the position of the control device, two cooling cycles (one cooling cycle in the cylinder head and one cooling cycle in the cylinder block) or a single cooling cycle is provided via the cylinder head and the cylinder block.

The control device is advantageously designed as a regulating element or valve and in particular has two possible positions. In the first position, the control device closes the connecting channel, so that no coolant can flow from the head cooling jacket into the block cooling jacket. In the second position, it opens the connecting channel so that the cylinder head cooling jacket and the cylinder block cooling jacket are in flow communication. The presence or absence of a flow connection between the head cooling jacket and the block cooling jacket therefore depends on the position of the control device. In the sense of the present invention, it may be that a flow connection is already present.

The cylinder head and the cylinder block are separated from each other, in particular by a cylinder head sealing plane. That is, the head seal plane is provided between the head and the block.

The cylinder head has a top-down cooling concept, i.e. the cooling liquid enters at the upper end of the cylinder head furthest from the flame deck provided between the cylinder head and the cylinder block, and flows via the cylinder head inlet channel into the rest of the cylinder head cooling jacket. The cooling fluid then flows around the drain channel, which is thereby cooled. The coolant is then led into the region of the central member and further into the inner annular portion of the cylinder head cooling jacket, from where it is led into the outer annular portion via at least one radial channel in the region of the exhaust and/or intake valve bridge. Thus, the cylinder head is cooled from top to bottom by the cylinder head cooling jacket. If the control device is in the first position, i.e. the connecting channel is closed, the coolant flows out of the cylinder head via the cylinder head drain. Whereas if the control means is in the second position, i.e. the connecting channel is open, the cooling liquid is further led into the cylinder. When the control device is in the open position, in particular no coolant flows out of the cylinder head via the cylinder head drain.

The flow of the coolant is also from top to bottom within the cylinder. The coolant is guided in particular from the discharge side to the intake side with a flow around the upper region of the cylinder liner facing the flame layer and is guided with a flow around the lower region of the cylinder liner facing away from the flame layer to a block discharge channel provided on the block discharge side. If the control device is in the first position, i.e. the connecting channel is closed, the cooling liquid enters the cylinder via the cylinder inlet channel. There is no flow connection between the cylinder block and the cylinder head. If, on the other hand, the control device is in the second position, i.e. the connecting channel is open, the cooling liquid is led from the cylinder head into the cylinder block via the connecting channel. In particular, when the control device opens a connecting channel to the cylinder head so that the cylinder head and the cylinder block are connected in flow communication, no cooling fluid is conducted from the cylinder block inlet channel into the cylinder block cooling jacket.

In principle, the coolant temperature increases from top to bottom as the cylinder head and cylinder block cool. It is therefore advantageous to conduct the coolant from the cylinder head into the cylinder block via the connecting channel in the event of a low or normal thermal load of the internal combustion engine. In the case of a high thermal load of the internal combustion engine, the cylinder head and the cylinder block are flowed through by two separate cooling circuits. That is, the temperature of the coolant at the tip of the cylinder head is higher than the coolant entering the cylinder cooling jacket via the cylinder inlet passage.

Advantageously, the connecting channel branches off from the head cooling jacket upstream of the head bank flow channel and enters the block cooling jacket downstream of the block inlet flow channel. Thereby ensuring that all of the cooling fluid from the head enters the block to also adequately cool the block.

Advantageously, a second control device is provided in the head jacket upstream of the cylinder head row flow channels. The desired coolant flow direction and coolant flow rate can thus also be achieved better. Although in principle it is sufficient to provide the control device only in the connecting channel, since the arrangement and design of the head cooling jacket is sufficient to introduce the entire cooling volume into the cylinder block. However, it is also of interest to provide a second control device in the cylinder head bank flow duct in order to avoid a small amount of coolant flowing over into the cylinder head bank flow duct at the location of the open control device. The control device can also be brought into an open position and a closed position, wherein the second control device is open when the coolant is to flow into the cylinder head bank flow duct and closed when the coolant is to flow into the connecting duct.

Suitably, a third control means is provided in the cylinder cooling jacket downstream of the cylinder inlet passage. The third control means allow a better control and distribution of the cooling liquid as well. It may be provided in addition to or instead of the second control device and prevents the coolant from flowing from the cylinder inlet channel into the cylinder cooling jacket in the closed position. In this case, in particular, the control device is open in the connecting channel. And in the open position, coolant may flow from the cylinder inlet channel into the cylinder cooling jacket.

It is advantageous to provide at least one busbar. The bus bar strip is provided and arranged for feeding the cylinder head cooling jacket and the cylinder head cooling jacket with a cooling fluid, wherein the cylinder head inlet channel and/or the cylinder head inlet channel can be supplied with the cooling fluid via the at least one bus bar strip. In this case, it may be advantageous if a common bus bar strip, which is arranged in particular in the cylinder, is provided for the cylinder head cooling jacket and the cylinder block cooling jacket, wherein it may also be advantageous if two bus bar strips are provided, one for the cylinder head cooling jacket and one for the cylinder block cooling jacket. If two bus bars are provided, they may both be disposed within the cylinder, or one within the cylinder head and one within the cylinder.

It is particularly advantageous if all the intake and discharge ducts and in particular also the bus bars are arranged on the same side of the longitudinal plane of the engine, in order to achieve a compact design of the internal combustion engine.

Advantageously, the cylinder head cooling jacket comprises a first cylinder head sub-cooling jacket and a second cylinder head cooling jacket, wherein the first cylinder head sub-cooling jacket and the second cylinder head cooling jacket are connected in flow communication by at least one overflow channel at least in the region of the central element. The first cylinder head sub-cooling jacket is thus connected in flow communication with the cylinder head inlet channel, and the second cylinder head cooling jacket is connected in flow communication with the connecting channel and the cylinder head outlet channel. The first cylinder head sub-cooling jacket is arranged at a distance from the flame deck and the second cylinder head cooling jacket adjoins the flame deck, wherein the first and the second cylinder head cooling jacket are separated from each other by an intermediate layer. The overflow is then arranged in the intermediate layer.

Suitably, the cylinder cooling jacket comprises a first cylinder sub-cooling jacket and a second cylinder sub-cooling jacket, wherein the first cylinder sub-cooling jacket and the second cylinder sub-cooling jacket are in flow communication via a further overflow. The first cylinder cooling jacket is oriented toward the fire floor and the second cylinder sub-cooling jacket is arranged on the side facing away from the fire floor. The connecting channel and the cylinder inlet channel open into the first cylinder sub-cooling jacket, wherein the cylinder outlet channel is connected to the second cylinder sub-cooling jacket. For an optimal uniform cooling of the cylinder liner, it is advantageous if the two cylinder block subflush jackets are arranged one above the other with respect to the cylinder axis, wherein the first cylinder block subflush jacket is arranged between the second cylinder block subflush jacket and the cylinder head sealing plane. It is advantageous here if the first cylinder block sub-cooling jacket and/or the second cylinder block sub-cooling jacket at least predominantly, preferably completely, surround the cylinder liner. Preferably, the further overflow and the connecting channel are arranged here on different sides of the longitudinal plane of the engine. This allows flow around the cylinder liner transverse to the longitudinal plane of the engine. In this case, it can be provided, in particular, that a further overflow is arranged on the inflow side.

The internal combustion engine can be designed for self-ignition or external ignition, preferably with an active or passive prechamber, i.e. with a so-called PCSI cylinder head (PCSI: prechamber spark ignition).

According to one embodiment of the invention, the cylinder head is designed as a single cylinder head. In principle, however, the use of the invention with multiple cylinder heads is possible.

Drawings

Additional features, advantages and effects are derived from the embodiments described below. The figures referred to herein show:

FIG. 1 shows a schematic diagram of an internal combustion engine according to the present disclosure;

fig. 2 shows a partial cross section of an internal combustion engine according to the invention.

Detailed Description

Fig. 1 shows a schematic representation of an internal combustion engine according to the invention with a cylinder head 2 and a cylinder block 4, which are separated from each other by a cylinder head sealing plane 18. In this case it is a single cylinder engine, but the engine according to the invention may also have two, three, four or more cylinders 6.

Fig. 2 shows a partial cross section of an internal combustion engine 1 according to the invention. The internal combustion engine 1 has a cylinder head 2 (e.g. a single cylinder head) and a cylinder block 5, which are connected to one another in the region of a flame deck 19 of the cylinder head 2.

The cylinder head sealing plane between the cylinder head 2 and the cylinder block 5 is indicated with reference number 18. The intake side 21 and the exhaust side 22 of the internal combustion engine 1 are arranged on different sides of an engine longitudinal plane 20 defined by a crankshaft and a cylinder axis ZA, not further shown.

The cylinder head 2, which is designed, for example, as a single cylinder head, has two inlet valves 23 and two exhaust valves 24, wherein the inlet channel 25 can be connected in flow communication with the combustion chamber via the inlet valves 23 and the outlet channel 26 can be connected in flow communication with the combustion chamber 27 via the exhaust valves 24.

Cooling cavities and flow paths for the coolant within the cylinder head 2 and the cylinder block 1 are partially schematically depicted in fig. 1. The so-called top-to-bottom cooling concept is used here. Within the scope of this document, this concept means in particular that the coolant flow is guided in the cylinder head 2 to the cylinder block 5 or the flame deck 19. In other words, the coolant is guided in one direction along the cylinder axis ZA from a region remote from the flame deck 19 or the cylinder block 3 to the flame deck 19 or the cylinder block 5, whereby a high cooling effect can be obtained particularly at the flame deck 19 subjected to a strong thermal load.

The cylinder head 2 has a cylinder head cooling jacket 3 with a cylinder head inlet channel 7 and a cylinder head outlet channel 8. The cylinder block 3 has a block cooling jacket 5 with a block inlet flow passage 9 and a block outlet flow passage 10. A connecting channel 11 is provided between the head cooling jacket 3 and the block cooling jacket 5, wherein a control device 12 is provided in the connecting channel 11. The control device 12 can be switched to two positions to achieve two states of coolant flow. Corresponding to the load and/or temperature relationship, a single water circulation through the cylinder head 2 and the cylinder block 5 or two separate water circulations for the cylinder head 2 and the cylinder block are realized. This results in a targeted better temperature control. In order to also be able to control and regulate the flow to the requirements better, the cylinder head row flow channel 8 has a second control device 13 and the cylinder block inlet flow channel 9 has a third control device 14.

The cylinder head 2 with the top-down cooling concept has in particular a head cooling jacket 3 with an upper first cylinder head sub-cooling chamber 31 and a lower second cylinder head sub-cooling chamber 32 separated from each other by an intermediate layer 26. The upper first cylinder head sub-cooling chamber 31 is therefore farther from the cylinder block 5 than the lower second cylinder head sub-cooling chamber 32 as viewed in one direction along the cylinder axis ZA. The upper first cylinder head sub-cooling chamber 31 and the lower second cylinder head sub-cooling chamber 32 are connected in flow communication in the region of the central element 15 via at least one overflow 16 in the intermediate layer 18. The term "central" here means, in particular in relation to the cylinder axis 8, that the central element 19 is arranged as close as possible to the cylinder axis 8 or in the cylinder axis. The component 19 can be formed in particular by an injector in the case of a diesel internal combustion engine or by a prechamber ignition unit in the case of a gasoline internal combustion engine.

As is usual in cylinder heads 2 with the concept of cooling from top to bottom, the cylinder head 2 is flowed through by coolant from above, i.e. from the region of the flame deck 4 remote from the cylinder head 2, downwards, i.e. towards the region close to the flame deck 4. Here, the coolant is supplied to the upper first head sub-cooling chamber 31, flows through the first head sub-cooling chamber 31 with cooling of the exhaust duct 24, enters the second head sub-cooling chamber 32 adjoining the lower side of the flame deck 19 via the overflow 16 arranged in the region of the central member 15 close to the cylinder axis 8.

The cylinder block 5 has an upper first cylinder sub-cooling jacket 51 and a lower second cylinder sub-cooling jacket 52 around the cylinder liner 28, which can be of dry or wet design. The first cylinder block sub-cooling jacket 51 is arranged here between the second cylinder block sub-cooling jacket 52 and the cylinder head sealing plane 18. In the state in which it is disposed at the cylinder liner 28, the first block sub-cooling jacket 51 and the second block sub-cooling jacket 52 are separated from each other. In other words, a first cylinder sub-cooling jacket 51 and a second cylinder sub-cooling jacket 52 are provided on the cylinder liner 28, which are spaced apart from each other along the cylinder liner 28, wherein the second cylinder sub-cooling jacket 51 is arranged on the side of the first cylinder sub-cooling jacket 51 facing away from the flame bed 19.

The first cylinder block sub-cooling jacket 51 is connected to the second cylinder block sub-cooling jacket 52 via another overflow 17. The other overflow 17 now extends in the cylinder 5 away from the cylinder liner 28.

The liquid coolant is supplied from the internal combustion engine 1 via a cylinder head inlet channel 7 to the cylinder head cooling jacket 3 of the cylinder head 2. The coolant flows from above downwards through the head cooling jacket 3 and thus cools the cylinder head 2. The cylinder head cooling jacket 3 can be connected in flow communication with the cylinder block cooling jacket 5 via a connecting channel 11 and a control device 12 provided therein. This is the case in the open position of the control device 12: the cooling liquid is led into the cylinder cooling jacket 5 via the connecting channel 11, flows through it from top to bottom and leaves the cylinder cooling jacket 5 via the cylinder row flow channel 10. If the control device 12 is in the second position, the connecting channel 11 is closed. The coolant here leaves the head jacket 3 via the block row flow duct 8. The cylinder cooling jacket 5 is supplied with coolant via a cylinder inlet channel 9, which, after cooling the cylinders 4, flows out again via a cylinder outlet channel 10.

Since the cylinder head jacket 3 has the first cylinder head sub-jacket 31 and the second cylinder head sub-jacket 32 and the block jacket 5 has the first block sub-jacket 51 and the second block sub-jacket 52, both the cylinder head 2 and the cylinder block 4 are guided in at least a plurality of, for example four, flow channels S1, S2, S3, S4 extending transversely to the engine longitudinal plane 20, wherein both flow channels S1, S2 in the cylinder head 2 and the flow channels S3, S4 in the cylinder block 5 intersect the engine longitudinal plane 20. The flow channel here represents a substantially continuous heat transfer surface between two 180 ° turns of the flow path through the head cooling chamber 3 and the block cooling chamber 5.

In this way, efficient cooling in the hot critical zone is obtained in both the head 2 and the block 4.

Claims

1. A liquid-cooled internal combustion engine (1), in particular a large engine, comprising a cylinder head (2) with a cylinder head cooling jacket (3) and a cylinder block (4) with a cylinder block cooling jacket (5) having a top-down cooling concept, wherein at least one cylinder (6) is arranged in the cylinder block (4), wherein the cylinder head cooling jacket (3) comprises a cylinder head inlet channel (7) and a cylinder head outlet channel (8), wherein the cylinder block cooling jacket (5) comprises a cylinder block inlet channel (9) and a cylinder block outlet channel (10),

it is characterized in that the utility model is characterized in that,

a connecting channel (11) is provided between the cylinder head cooling jacket (3) and the cylinder block cooling jacket (5), wherein a control device (12) is provided in the connecting channel, so that the cylinder head cooling jacket (3) and the cylinder block cooling jacket (5) are optionally connected in a flow-through manner.

2. An internal combustion engine (1) according to claim 1, characterized in that the connecting channel (11) branches off from the head cooling jacket (3) upstream of the head row flow channel (8) and enters the block cooling jacket (5) downstream of the block inlet flow channel (9).

3. An internal combustion engine (1) according to claim 1 or 2, characterized in that a second control device (13) is arranged in the head cooling jacket (3) upstream of the head bank flow channel (8).

4. An internal combustion engine (1) according to claim 1 or 2, characterized in that a third control means (14) is provided in the cylinder cooling jacket (5) downstream of the cylinder inlet channel (9).

5. Internal combustion engine (1) according to claim 1 or 2, characterized in that at least one busbar is provided.

6. Internal combustion engine (1) according to claim 1 or 2, characterized in that the head cooling jacket (3) comprises a first head sub-cooling jacket (31) and a second head sub-cooling jacket (32), wherein the first head sub-cooling jacket (31) and the second head sub-cooling jacket (32) are connected in flow communication by at least one overflow (16) at least in the region of the central element (15).

7. An internal combustion engine (1) according to claim 1 or 2, characterized in that the cylinder cooling jacket (5) comprises a first cylinder cooling sub jacket (51) and a second cylinder cooling sub jacket (52), wherein the first cylinder cooling sub jacket (51) and the second cylinder cooling sub jacket (52) are in flow connection via a further overflow (17).