CN107781021B

CN107781021B - Engine cooling system for vehicle and vehicle

Info

Publication number: CN107781021B
Application number: CN201610763725.5A
Authority: CN
Inventors: 王江涛; 杨晓勇; 李宇飞; 高峰; 胡广进; 申荣伟; 张士伟
Original assignee: Great Wall Motor Co Ltd
Current assignee: Great Wall Motor Co Ltd
Priority date: 2016-08-30
Filing date: 2016-08-30
Publication date: 2020-02-28
Anticipated expiration: 2036-08-30
Also published as: CN107781021A

Abstract

The invention provides an engine cooling system for a vehicle and a vehicle, wherein the engine cooling system comprises: a cylinder body water jacket; the engine oil cooler is connected with the cylinder water jacket; the first water pump is connected with the engine oil cooler and selectively connected with the cylinder water jacket; the water inlet of the EGR cooler is selectively connected with the first water pump, and the water outlet of the EGR cooler is selectively connected with the oil cooler and/or the first water pump. The cooling system can utilize the EGR cooler to recover the heat of the exhaust gas and supply the heat to the oil cooler, so that the temperature of the engine oil in the oil cooler is quickly raised under the condition of low load, and the bypass exhaust gas is cooled under the working condition of high load, thereby avoiding the negative influence on the performance of the three-way catalyst caused by directly discharging the high-temperature exhaust gas into the three-way catalyst.

Description

Engine cooling system for vehicle and vehicle

Technical Field

The invention relates to the technical field of vehicles, in particular to an engine cooling system for a vehicle and the vehicle.

Background

The current cooled EGR technology is well developed and introduces exhaust gas from the exhaust end into the combustion chamber, lowering the combustion temperature. EGR technology is effective in reducing NOx emissions, but has ignored the key factor that EGR technology can serve as a source of recovered heat.

Furthermore, the prior art engines require bypassing part of the exhaust gas at very high loads, while taking into account the fact that higher exhaust gas temperatures can damage the catalyst, a mixture enrichment strategy, i.e. multiple injections, is used, which leads to increased fuel consumption.

Disclosure of Invention

In view of the above, the present invention is directed to an engine cooling system, which can recover heat of exhaust gas by using an EGR cooler and supply the heat to an oil cooler, so that the temperature of oil in the oil cooler is rapidly raised under a low load condition, and the bypassed exhaust gas is cooled under a high load condition, thereby preventing high-temperature exhaust gas from being directly discharged into a three-way catalyst to adversely affect the performance of the catalyst.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

an engine cooling system for a vehicle, comprising: a cylinder body water jacket; the engine oil cooler is connected with the cylinder water jacket; the first water pump is connected with the engine oil cooler and selectively connected with the cylinder water jacket; the water inlet of the EGR cooler is selectively connected with the first water pump, and the water outlet of the EGR cooler is selectively connected with the oil cooler and/or the first water pump.

Further, the engine cooling system further includes:

a first on-off valve having first through third ports, the first port being connected to the first water pump, the second port being connected to the block jacket, the third port being connected to the water inlet of the EGR cooler, the first port being selectively in communication with the second port and/or the third port;

the second on-off valve is provided with fourth to sixth ports, the fourth port is connected with a water outlet of the EGR cooler, the fifth port is connected with the first water pump, the sixth port is connected with the engine oil cooler, and the fourth port is selectively connected with the fifth port and/or the sixth port.

Further, an exhaust port of the engine is connected to an intake port of the EGR cooler, and an exhaust port of the EGR cooler is selectively connected to an intake port of the engine and/or a three-way catalyst of the vehicle.

Further, the engine cooling system further includes: a third shutoff valve having seventh through ninth ports, the seventh port being connected to the exhaust port of the EGR cooler, the eighth port being connected to the intake port of the engine, the ninth port being connected to a three-way catalyst of the vehicle, the seventh port being selectively communicated with the eighth port and/or the ninth port.

Further, the engine cooling system further includes: the cylinder cover water jacket is connected with the cylinder body water jacket, and the fan heater is connected with the first water pump.

Further, the engine cooling system further includes: and the water tank is respectively connected with the first water pump and the fan heater.

Further, a thermostat is arranged between the water tank and the first water pump.

Further, the engine cooling system further includes: and the exhaust gas outlet of the supercharger is selectively connected with a three-way catalytic converter of the vehicle.

Further, a bypass valve is provided on the supercharger, the bypass valve being selectively connectable to an intake port of the three-way catalyst and/or the EGR cooler.

Another object of the present invention is to provide a vehicle having the above engine cooling system.

Compared with the prior art, the engine cooling system has the following advantages:

(1) according to the engine cooling system, the first on-off valve, the second on-off valve and the third on-off valve are arranged, so that the engine oil in the engine oil cooler can be heated under a low-load working condition, and the temperature of the engine oil in the engine oil cooler can be freely adjusted under various working conditions.

(2) The engine cooling system can lead the waste gas discharged from the bypass valve to pass through the EGR cooler to cool the part of the waste gas under the high-load working condition by controlling the communication state of the third stop valve, thereby avoiding the high-temperature waste gas from being directly discharged into the three-way catalyst to reduce the activity of the catalyst.

Compared with the prior art, the vehicle has the following advantages:

according to the vehicle, the engine cooling system is arranged, so that the thermal management performance of the vehicle can be greatly improved, the combustion under the cold starting working condition and the cold working condition is improved, the oil consumption of the vehicle is reduced, and the performance of the engine of the vehicle is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a water cycle of an engine cooling system according to an embodiment of the present invention;

fig. 2 is a schematic diagram of gas supply of an engine cooling system according to an embodiment of the present invention.

Description of reference numerals:

the engine cooling system 100 is provided with a cooling system,

a block water jacket 101, an oil cooler 102, a first water pump 103, an EGR cooler 104,

a first on/off valve 105, a first port 105a, a second port 105b, a third port 105c,

a second cut-off valve 106, a fourth port 106a, a fifth port 106b, a sixth port 106c,

a third shut-off valve 110, a seventh port 110a, an eighth port 110b, a ninth port 110c,

a supercharger 107, a three-way catalyst 109, a second water pump 111, a cylinder head water jacket 112, a warm air blower 113, a water tank 114, a thermostat 115 and an intercooler 116;

an engine 200.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

With the stricter and stricter regulations on oil consumption and emission, the improvement of the thermal management capability of the engine is inevitable, particularly under the cold working condition of the engine, the related literature shows that the emission of the engine in 30s of warm-up accounts for more than 90% of the emission of the whole NEDC (new European driving cycle), and meanwhile, the problem of high oil consumption is brought. Therefore, the combustion of the engine in the cold start condition and the cold state condition needs to be improved urgently.

In addition, with the rapid development of automobile technology, people not only pursue high performance and low oil consumption of automobiles, but also pay more attention to driving comfort brought by the automobiles. Especially in cold conditions, people need to be provided with warm air immediately after starting the vehicle.

Future regulations and emission regulations will become more stringent, such as wltp (worldwide bright vehicle procedures) which will replace NEDC test cycles, the latter being more focused on the real fuel consumption of the car. The most significant change is that the specific gravity of the high-load working condition is obviously increased. Thus, reducing high load fuel consumption will be a primary problem for all vehicle enterprises. The problem of concentration of high fuel consumption at high engine load is how to reduce the exhaust gas temperature.

If the engine can be ensured to be in a better running state under any working condition, the cooling system must be accurate and refined and can be adjusted quickly. Recently, each vehicle enterprise also continuously provides respective heat management technology to realize fine adjustment of the temperature of the cooling water.

The current technology for cooling EGR (exhaust gas recirculation) is developed to be mature, and the exhaust gas is led from an exhaust end to enter a combustion chamber to reduce the combustion temperature. The EGR technology can effectively reduce NOx emission, optimize combustion phase and improve combustion efficiency. But one neglects the key factor that EGR can serve as a source of recovered heat.

Under the condition of environmental conditions, the supercharger needs sufficient exhaust energy to build the intake pressure under the condition of low load, and if the technology of EGR heat source recovery exists, the exhaust energy of the supercharger is weakened. Even if the technology can be used for diesel engines, the range of the operating conditions is extremely narrow because of the efficiency of the supercharger.

This patent is through changing EGR subassembly pipeline, has successfully solved its problem that can retrieve the heat on the gasoline engine. Meanwhile, due to the characteristics of the gasoline engine, the technology is completely allowed to work under wider working conditions. The engine cooling system of the embodiment of the invention is mainly applied to supercharged gasoline engines, high-pressure EGR technology (namely EGR works only under high load and high working condition) and a double-circulation combustion mode (namely a supercharger does not work under low load, and exhaust gas directly flows into a three-way catalyst through a bypass valve), but is not limited to the above.

An engine cooling system 100 for a vehicle according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings in conjunction with the embodiment.

As shown in fig. 1, an engine cooling system 100 for a vehicle according to an embodiment of the present invention includes a block water jacket 101, an oil cooler 102, a first water pump 103, and an EGR cooler 104.

The cylinder water jacket 101, the oil cooler 102, the first water pump 103 and the EGR cooler 104 are provided with a water inlet and a water outlet, wherein the water inlet of the oil cooler 102 is connected with the water outlet of the cylinder water jacket 101, the first water pump 103 is connected with the water outlet of the oil cooler 102, and the first water pump 103 is selectively connected with the cylinder water jacket 101.

When the first water pump 103 is connected to the block water jacket 101, cooling water can be circulated between the first water pump 103 and the block water jacket 101; when the first water pump 103 is disconnected from the block water jacket 101, the cooling water cannot flow between the first water pump 103 and the block water jacket 101, and the cooling water in the block water jacket 101 is relatively stationary.

The water inlet of the EGR cooler 104 is optionally connected to the first water pump 103, and the water outlet of the EGR cooler 104 is optionally connected to the oil cooler 102 and/or the first water pump 103.

When the water inlet of the EGR cooler 104 is connected to the first water pump 103, cooling water may flow from the first water pump 103 to the EGR cooler 104; when the water inlet of the EGR cooler 104 is disconnected from the first water pump 103, the cooling water cannot flow from the first water pump 103 to the EGR cooler 104.

When the water outlet of the EGR cooler 104 is connected to the first water pump 103, coolant may flow from the DGR cooler to the first water pump 103; when the water outlet of the EGR cooler 104 is connected to the oil cooler 102, coolant may flow from the EGR cooler 104 to the oil cooler 102.

Alternatively, as shown in FIG. 1, the engine cooler system may include a first block valve 105 and a second block valve 106.

The first on-off valve 105 has a first port 105a, a second port 105b, and a third port 105c, the first port 105a being connected to the first water pump 103, the second port 105b being connected to the block water jacket 101, the third port 105c being connected to the water inlet of the EGR cooler 104, the first port 105a being in communication with the second port 105b and/or the third port 105c, as appropriate.

When the first port 105a is communicated with the second port 105b, the first water pump 103 is connected with the cylinder water jacket 101, the cooling liquid can flow from the first water pump 103 to the cylinder water jacket 101, the cooling water in the cylinder water jacket 101 can flow, and further the cooling water can cool the cylinder, so that the temperature of the cylinder is prevented from being too high; when the first port 105a communicates with the third port 105c, the first water pump 103 is connected to the EGR cooler 104, and the cooling water can flow from the first water pump 103 to the EGR cooler 104.

When the first port 105a is communicated with the second port 105b and the third port 105c, the first water pump 103 is respectively connected with the cylinder water jacket 101 and the EGR cooler 104, cooling water can flow from the first water pump 103 to the cylinder water jacket 101 and the EGR cooler 104, and the high-temperature cooling liquid passing through the EGR cooler 104 can heat the oil in the oil cooler 102, so that the oil can rapidly reach a proper working temperature.

Of course, it is understood that the first port 105a may also communicate with the second port 105b and the third port 105c simultaneously, in which case the first water pump 103 is directly connected to both the block water jacket 101 and the EGR cooler 104 simultaneously, and the coolant may flow from the first water pump 103 to both the block water jacket 101 and the EGR cooler 104 simultaneously. And the flow rate of the cooling fluid flowing from the first port 105a to the second port 105b and/or the third port 105c is adjustable, the flow rate of the cooling fluid may be gradually increased or decreased.

The second cut-off valve 106 has a fourth port 106a, a fifth port 106b, and a sixth port 106c, the fourth port 106a is connected to the water outlet of the EGR cooler 104, the fifth port 106b is connected to the first water pump 103, the sixth port 106c is connected to the water inlet of the oil cooler 102, and the fourth port 106a is selectively communicated with the fifth port 106b and/or the sixth port 106 c.

When the fourth port 106a communicates with the fifth port 106b, the EGR cooler 104 may be directly connected to the first water pump 103, and cooling water may flow from the EGR cooler 104 to the first water pump 103.

When the fourth port 106a is connected to the sixth port 106c, the EGR cooler 104 may be directly connected to the oil cooler 102, and cooling water may flow from the EGR cooler 104 to the oil cooler 102.

When the fourth port 106a communicates with both the fifth port 106b and the sixth port 106c, the EGR cooler 104 is connected to both the first water pump 103 and the oil cooler 102, and the cooling water can flow from the EGR cooler 104 to both the first water pump 103 and the oil cooler 102.

By adjusting the open/close states of the fourth port 106a, the fifth port 106b, and the sixth port 106c, the temperature of the oil in the oil cooler 102 can be adjusted so that the temperature of the oil is always maintained at an appropriate temperature without being too high or too low.

The exhaust of the engine is connected to the intake of an EGR cooler 104 and the exhaust of the EGR is optionally connected to the intake of the engine and/or a three-way catalyst 109 of the vehicle.

When the exhaust port of the EGR cooler 104 is connected to the intake port of the engine, part of the exhaust gas discharged from the engine can be returned to the combustion chamber of the engine again, and the temperature of part of the exhaust gas can be reduced when the part of the exhaust gas passes through the EGR cooler 104, so that the impact of high-temperature exhaust gas on the combustion environment of the combustion chamber is avoided, and the content of NOx in the exhaust gas is reduced to a certain extent.

When the exhaust port of the EGR cooler 104 is connected to the three-way catalyst 109, at least a part of the exhaust gas discharged from the engine 200 may enter the three-way catalyst 109 after being cooled by the EGR cooler 104, thereby preventing the high-temperature exhaust gas from directly entering the three-way catalyst 109 and then damaging the three-way catalyst 109.

In order to avoid the damage of the exhaust gas to the catalyst in the three-way catalyst, a multi-injection strategy is generally adopted, and although the temperature of the exhaust gas can be reduced, the oil consumption is greatly increased and the harmful substances in the exhaust gas are also increased in response.

This application is through the waste gas process EGR cooler 104 with the bypass for the exhaust gas temperature obtains reducing, avoids high temperature waste gas to cause the influence to the activity of the catalyst in the three way catalyst converter.

The engine cooling system 100 further comprises a supercharger 107, the exhaust inlet of the supercharger 107 being connected to the exhaust of the engine, the exhaust outlet of the supercharger 107 being optionally connected to a three-way catalyst 109.

The supercharger 107 is also provided with a bypass valve which is selectively connected to the three-way catalyst 109 and/or the intake port of the EGR cooler 104. Alternatively, the intake of the EGR cooler 104 may be connected to a bypass valve of the supercharger 107.

When the vehicle is in a low-load condition, the exhaust gas can enter the three-way catalyst 109 through the bypass valve instead of passing through the supercharger 107; when the vehicle is in a high-load working condition, part of exhaust gas can enter the supercharger 107 and then enter the three-way catalyst 109, and part of exhaust gas can be discharged through the bypass valve to achieve the purpose of pressure relief, and the part of exhaust gas can enter the EGR cooler 104 and then enter the three-way catalyst 109 after being cooled by the EGR cooler 104, so that the influence of the high-temperature exhaust gas directly discharged into the three-way catalyst 109 on the three-way catalyst 109 is avoided.

As shown in fig. 2, in some embodiments of the present invention, the engine cooling system 100 further includes a third shut-off valve 110, the third shut-off valve 110 having a seventh port 110a, an eighth port 110b, and a ninth port 110c, the seventh port 110a being connected to the exhaust port of the EGR cooler 104, the eighth port 110b being connected to the intake port of the engine 200, the ninth port 110c being connected to the three-way catalyst 109, the seventh port 110a being selectively in communication with the eighth port 110b and/or the ninth port 110 c.

When the seventh port 110a communicates with the eighth port 110b, the exhaust port of the EGR cooler 104 is connected to the intake port of the engine, and part of the exhaust gas can pass through the EGR cooler 104 and return to the combustion chamber of the engine, thereby reducing the content of NOx in the exhaust gas to some extent.

When the seventh port 110a communicates with the ninth port 110c, the exhaust port of the EGR cooler 104 is connected to the three-way catalyst 109, and part of the exhaust gas can pass through the EGR cooler 104 and then enter the three-way catalyst 109. Thereby reducing the exhaust gas temperature and avoiding the influence of the exhaust gas on the activity of the catalyst in the three-way catalyst 109.

When the seventh port 110a is connected to both the eighth port 110b and the ninth port 110c, exhaust gas discharged from the EGR cooler 104 may simultaneously enter the combustion chamber of the engine 200 and the three-way catalyst 109.

The engine cooling system 100 further comprises a second water pump 111, a cylinder cover water jacket 112 and a warm air blower 113, the second water pump 111, the cylinder cover water jacket 112 and the warm air blower 113 are sequentially connected, the cylinder cover water jacket 112 is connected with the cylinder body water jacket 101, and the warm air blower 113 is connected with the first water pump 103.

When the engine is under the low-load working condition, the cooling water in the cylinder water jacket 101 is in a relatively static state, the second water pump 111, the cylinder cover water jacket 112 and the warm air blower 113 form a small circulation, the cooling water in the cylinder cover water jacket 112 can enter the warm air blower 113 after being heated, and then the temperature in the cab can be improved when the engine is under the low-load working condition and the warm air heating working condition, so that the driving comfort of a driver is improved, and the driving experience of the driver is improved.

The engine cooling system 100 further includes a water tank 114, and the water tank 114 is connected to the first water pump 103 and the heater fan 113, respectively. When the engine is in a high load condition, the coolant in the water tank 114 may participate in the cooling cycle, cooling the cylinder block, cylinder head, and oil cooler 102.

A thermostat 115 may be disposed between the water tank 114 and the first water pump 103, and when the thermostat 115 is turned on, the water tank 114 may participate in a cooling cycle to cool various components. Of course, the structure and principle of the thermostat 115 are well known in the art and will not be described in detail herein.

The engine cooling system 100 of the embodiment of the invention further comprises an intercooler 116, wherein an air inlet of the intercooler 116 is connected with an air outlet of the supercharger 107, and an air outlet of the intercooler 116 is connected with an air inlet of the engine.

Optionally, the eighth port 110b is connected between the intercooler 116 and the engine. The exhaust gas discharged from the EGR cooler 104 may be mixed with air cooled by the intercooler 116 and then introduced together into the combustion chamber of the engine 200.

Various operating conditions of the engine of the present embodiment are described in detail below.

Cold start conditions:

the first port 105a of the first on-off valve 105 communicates with the third port 105c, and the first port 105a is disconnected from the second port 105 b; the fourth port 106a and the fifth port 106b of the second cut-off valve 106 are communicated, and the fourth port 106a and the sixth port 106c are disconnected; the third shut-off valve 110 is in a closed state, i.e., the seventh port 110a is shut off from the eighth port 110b, and the seventh port 110a is also shut off from the ninth port 110 c.

At this time, since the first port 105a is disconnected from the second port 105b, the cooling water in the block water jacket 101 is in a stationary state, and the temperature of the block and the cylinder head of the engine can be rapidly increased to reach a suitable operating temperature of the engine. The oil cooler 102 is also in a relatively stationary state because it also has no source of cooling water.

The first water pump 103 and the EGR cooler 104 form a micro-circulation, and since the engine 200 recovers and utilizes part of the exhaust gas only under high load, the performance of the whole engine is not affected by the coolant entering the EGR cooler 104. On the contrary, due to the intervention of the EGR cooler 104, the coolant can flow, and the first water pump 103 is not in a dead state, so that the mechanical loss of the whole machine is greatly reduced.

Meanwhile, the second water pump 111 can work to form circulation between the warm air blower 113 and the cylinder cover water jacket 112, hot water in the cylinder cover water jacket 112 can enter the warm air blower 113, a heat source is provided for the warm air blower 113, it is guaranteed that a proper temperature can be obtained in a cockpit at the initial starting stage of the engine 200, and driving experience of a driver is improved.

In this condition, exhaust gas does not pass through the EGR cooler 104 and the cooling water in the EGR cooler 104 does not heat the oil in the oil cooler 102. This is because, at the initial stage of start of the engine 200, the catalyst in the three-way catalyst 109 needs to be raised to an appropriate operating temperature, and therefore, in the cold start condition, the exhaust gas is discharged directly into the three-way catalyst 109 through the bypass valve, raising the temperature of the catalyst in the three-way catalyst 109.

And (3) warming-up working condition:

the first port 105a of the first on-off valve 105 communicates with the third port 105c, and the first port 105a is disconnected from the second port 105 b; the fourth port 106a in the second cut-off valve 106 communicates with the sixth port 106c, and the fourth port 106a is cut off from the fifth port 106 b; the seventh port 110a of the third cut-off valve 110 communicates with the ninth port 110c, and the seventh port 110a is cut off from the eighth port 110 b.

At this time, since the first port 105a is disconnected from the second port 105b, the cooling water in the block water jacket 101 is still in a stationary state, and the temperatures of the block and the cylinder head of the engine 200 can continue to rise to reach the appropriate operating temperature of the engine.

And the first water pump 103, the EGR cooler 104 and the oil cooler 102 form a micro-circulation, and the first water pump 103 works and drives cooling water to flow, so that the mechanical loss of the whole machine is greatly reduced.

Further, since the seventh port 110a communicates with the ninth port 110c, all of the exhaust gas discharged from the engine passes through the EGR cooler 104 and enters the three-way catalyst 109. The exhaust gases are in heat exchange with the cooling water in the EGR cooler 104, i.e. the exhaust gases may heat the cooling water in the EGR cooler 104. The heated cooling water may flow into oil cooler 102 to heat the oil in oil cooler 102 such that the temperature of the oil is rapidly increased to a suitable operating temperature.

Meanwhile, the second water pump 111 continues to work to form circulation between the warm air blower 113 and the cylinder cover water jacket 112, hot water in the cylinder cover water jacket 112 can enter the warm air blower 113, a heat source is provided for the warm air blower 113, the temperature in the cockpit is rapidly increased, and the driving experience of a driver is improved.

And (3) working condition after warming up:

the water temperature of the cooling water in the block water jacket 101 and the head water jacket 112 is increased, the first port 105a in the first on-off valve 105 communicates with the second port 105b and the third port 105c at the same time, and the on-opening degree between the first port 105a and the second port 105b in the first on-off valve 105 is gradually increased and the on-opening degree between the first port 105a and the third port 105c is gradually decreased.

In this case, the cooling cycle is at least two: a large circulation formed among the first water pump 103, the block water jacket 101, the head water jacket 112, and the heater fan 113, and a small circulation formed among the first water pump 103, the EGR cooler 104, and the oil cooler 102. The large circulation appropriately lowers the temperatures of the block water jacket 101 and the head water jacket 112, and can supply cold water to the supply oil cooler 102, with the amount of circulating water gradually increasing. While the small circulation still absorbs the heat of the exhaust gas through the EGR cooler 104 and supplies it to the oil cooler 102, eventually ensuring that the proper oil temperature is adjusted, with its flow gradually decreasing.

In this condition, the second water pump 111 is turned off, and the heat of the warm air blower 113 is supplied through the head water jacket 112. Of course, it can be understood that the temperature of the cooling water in the cylinder water jacket 101 is also raised, and can also be used as a heat source for the fan heater 113.

Under a large load condition:

the temperature of the cooling water in the block water jacket 101 and the head water jacket 112 continues to rise, the thermostat 115 opens, and the water tank 114 is switched on for a large cycle to lower the temperature of the coolant in the engine.

The first port 105a in the first on-off valve 105 communicates with both the second port 105b and the third port 105c, the fourth port 106a in the second on-off valve 106 communicates with the fifth port 106b, the fourth port 106a is disconnected from the sixth port 106c, and the seventh port 110a in the third on-off valve 110 communicates with the eighth port 110 b.

In this condition, circulation is formed between the first water pump 103 and the EGR cooler 104, and water in the water tank 114 can flow into the EGR cooler 104 through the first water pump 103. The first water pump 103 may directly supply water to the EGR cooler 104 to cool down the exhaust gas recirculated to the combustion chamber, ensuring that it has an optimal temperature.

Circulation is formed among the first water pump 103, the block water jacket 101, the oil cooler 102, and the water tank 114, which can lower the temperature of the block water jacket 101 and adjust the temperature of the oil in the oil coolant.

Circulation is formed among the first water pump 103, the cylinder water jacket 101, the cylinder head water jacket 112 and the water tank 114, so that the temperatures of the cylinder water jacket 101 and the cylinder head water jacket 112 can be reduced, and the negative influence on the performance of the engine caused by overhigh temperatures of the cylinder body and the cylinder head is avoided.

High load condition:

as the engine speed increases, the boost pressure increases and the temperature of the exhaust gas increases, and at this time, part of the exhaust gas needs to be discharged from the bypass valve of the supercharger 107 to ensure that the supercharger 107 has proper output torque. However, if the high-temperature exhaust gas is directly bypassed to the three-way catalyst 109, the catalyst in the three-way catalyst 109 is damaged, and the activity of the catalyst is reduced.

Accordingly, the seventh port 110a of the third shut-off valve 110 can be simultaneously communicated with the eighth port 110b and the ninth port 110c, and thus part of the exhaust gas discharged from the bypass valve can be cooled by the EGR cooler 104, thereby preventing the catalyst in the three-way catalyst 109 from being damaged by the high-temperature exhaust gas.

The open state of the first 105 and second 106 on-off valves and the cooling cycle involved are as described above for the heavy load conditions and will not be described in detail here.

It should be noted that, in the above-mentioned several operating conditions, the temperature of the oil in the oil cooler 102 can be adjusted by adjusting the open/close states of the fourth port 106a, the fifth port 106b, and the sixth port 106c in the second cut-off valve 106, so as to ensure that the oil is always at a proper temperature.

The engine cooling system 100 according to the embodiment of the present invention, by providing the first on-off valve 105, the second on-off valve 106, and the third on-off valve 110, can heat the engine oil in the engine oil cooler 102 under a low load condition, and can freely adjust the temperature of the engine oil in the engine oil cooler 102 under various conditions.

By controlling the communication state of the third shutoff valve 110, the exhaust gas discharged from the bypass valve can be cooled by passing through the EGR cooler 104 under a high load condition, and the high-temperature exhaust gas is prevented from being directly discharged into the three-way catalyst 109 to reduce the activity of the catalyst.

The engine cooling system 100 of the present application has at least the following advantages:

when in cold start, the cooling water of the whole machine is in a relatively static non-circulating state, the machine is quickly warmed up, and meanwhile, the exhaust gas is directly discharged into the three-way catalyst 109, so that the catalyst in the three-way catalyst 109 is quickly heated up through the high-temperature exhaust gas. When the air conditioner is in cold start, under the action of the second water pump 111, hot water is supplied to the warm air blower 113, warm air supply of the cockpit is achieved, and driving comfort of a driver is guaranteed.

The cooling water of the whole engine under the warm-up working condition still keeps a relatively static non-circulation state, and the temperature of the whole engine is further increased, so that the engine quickly reaches an optimal running state; under the warm-up condition, exhaust gas passes through EGR cooler 104, and EGR cooler 104 retrieves the exhaust gas heat for the temperature of the cooling water in it obtains promoting, and this high temperature cooling water can be supplied to oil cooler 102, and then the quick engine oil temperature in lifting machine oil cooler 102 makes engine oil reach optimum operating condition fast.

After warming up, the second water pump 111 is closed, warm air is supplied by switching to the cylinder cover water jacket 112, and mechanical loss is reduced; and the EGR cooler 104 and the cooling water in the cylinder water jacket 101 are supplied to the oil cooler 102 at the same time, ensuring a better oil temperature.

Under a large-load working condition, the cooling water pump directly supplies the cooling water to the EGR cooler 104 to cool the waste gas, and the proper temperature of the waste gas is ensured to be supplied to the combustion chamber;

under the working condition of high rotating speed and high load, the exhaust gas discharged from the bypass valve directly flows out through the EGR cooler 104, and then the cooled exhaust gas enters the three-way catalyst 109, so that the lower exhaust gas temperature is ensured, and the current commonly used exhaust gas enrichment strategy is avoided.

The whole engine cooling system 100 has definite structural arrangement, and the control means and the control parts are conventional and easy to realize in a groove.

The whole system can switch the optimal circulating water path according to different working conditions of the engine 200, ensure the optimal running state of the engine, and adjust the temperature of the engine oil in the engine oil cooler 102 at any time, so that the temperature of the engine oil is always in the optimal working state.

The vehicle of the embodiment of the invention is briefly described below.

The vehicle comprises the engine cooling system 100 of the embodiment, and the vehicle is provided with the engine cooling system 100, so that the thermal management capacity of the vehicle is improved, the combustion under the cold starting working condition and the cold working condition is improved, the oil consumption of the vehicle is reduced, and the performance of an engine of the vehicle is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. An engine cooling system (110) for a vehicle, comprising:

a cylinder water jacket (101);

the oil cooler (102), the oil cooler (102) is connected with the cylinder water jacket (101);

a first water pump (103), wherein the first water pump (103) is connected with the oil cooler (102), and the first water pump (103) is selectively connected with the cylinder water jacket (101);

an EGR cooler (104), wherein a water inlet of the EGR cooler (104) is selectively connected with the first water pump (103), and a water outlet of the EGR cooler (104) is selectively connected with the oil cooler (102) and/or the first water pump (103);

a first on-off valve (105), the first on-off valve (105) having first to third ports (105c), the first port (105a) being connected to the first water pump (103), the second port (105b) being connected to the block water jacket (101), the third port (105c) being connected to a water inlet of the EGR cooler (104), the first port (105a) being selectively communicable with the second port (105b) and/or the third port (105 c);

a second shut-off valve (106), the second shut-off valve (106) having fourth to sixth ports (106c), the fourth port (106a) being connected to a water outlet of the EGR cooler (104), the fifth port (106b) being connected to the first water pump (103), the sixth port (106c) being connected to the oil cooler (102), the fourth port (106a) being selectively connected to the fifth port (106b) and/or the sixth port (106 c).

2. Engine cooling system (110) for a vehicle according to claim 1, characterised in that the exhaust of the engine is connected to the inlet of the EGR cooler (104), and that the exhaust of the EGR cooler (104) is optionally connected to the inlet of the engine and/or to a three-way catalyst (109) of the vehicle.

3. The engine cooling system (110) for a vehicle according to claim 2, further comprising: a third shut-off valve (110), the third shut-off valve (110) having seventh to ninth ports (110c), the seventh port (110a) being connected to an exhaust port of the EGR cooler (104), the eighth port (110b) being connected to an intake port of the engine, the ninth port (110c) being connected to a three-way catalyst (109) of the vehicle, the seventh port (110a) being selectively communicated with the eighth port (110b) and/or the ninth port (110 c).

4. The engine cooling system (110) for a vehicle according to claim 1, further comprising: the water heater comprises a second water pump (111), a cylinder cover water jacket (112) and a warm air blower (113), wherein the second water pump (111), the cylinder cover water jacket (112) and the warm air blower (113) are sequentially connected, the cylinder cover water jacket (112) is connected with a cylinder body water jacket (101), and the warm air blower (113) is connected with the first water pump (103).

5. The engine cooling system (110) for a vehicle according to claim 4, comprising: and the water tank (114), the water tank (114) is respectively connected with the first water pump (103) and the warm air blower (113).

6. The engine cooling system (110) for a vehicle according to claim 5, characterized in that a thermostat (115) is further provided between the water tank (114) and the first water pump (103).

7. The engine cooling system (110) for a vehicle according to claim 2, further comprising: a supercharger (107), an exhaust gas inlet of the supercharger (107) being connected to an exhaust of the engine, an exhaust gas outlet of the supercharger (107) being selectively connectable to a three-way catalyst (109) of the vehicle.

8. Engine cooling system (110) for a vehicle according to claim 7, characterized in that a bypass valve is also provided on the supercharger (107), which bypass valve is selectively connectable to the air intake of the three-way catalyst (109) and/or the EGR cooler (104).

9. A vehicle, characterized in that an engine cooling system (110) according to any one of claims 1-8 is provided.