EGR cooling system of diesel engine

Abstract

The utility model discloses a diesel engine EGR cooling system which comprises an engine body, a water pump and a machine body, an EGR water taking pipe is fixedly arranged on the engine body, an EGR water inlet rubber pipe is fixedly connected to the EGR water taking pipe, an EGR cooler is fixedly arranged on the engine body, an EGR valve seat is fixedly arranged on the engine body, and an EGR water inlet rubber pipe is fixedly connected to the EGR water taking pipe. The EGR valve seat is provided with an EGR valve, the EGR cooler is fixedly connected with the EGR valve, the EGR valve seat is fixedly connected with an EGR water return rubber pipe, the engine body is fixedly provided with an exhaust manifold, the exhaust manifold is fixedly connected with the EGR valve, the EGR cooler is fixedly connected with an EGR pipe, the tail end of the EGR pipe is fixedly connected with an air inlet connecting pipe, and the tail end of the EGR pipe is fixedly connected with an air outlet connecting pipe. The air inlet connecting pipe is fixedly connected with an air inlet manifold. According to the EGR cooler, cooling water enters from the lower portion of the EGR cooler, after EGR waste gas is cooled, the cooling water flows out from the upper portion of the EGR cooler, and the temperature of the EGR waste gas can be effectively reduced in a heat convection mode.

Description

Technical Field

[0001] This utility model relates to the technical field of diesel engines, and in particular to an EGR cooling system for diesel engines. Background Technology

[0002] Diesel engine fuel (diesel) has a high calorific value and a large excess air coefficient λ. The high-temperature, oxygen-rich environment during combustion leads to the formation of large amounts of nitrogen oxides (NOx). The EGR (Exhaust Gas Recirculation) system in diesel engines is a technology that separates the exhaust gases after combustion and reintroduces them into the engine cylinders for combustion. Its main purpose is to reduce NOx and optimize fuel consumption under partial load. The portion of exhaust gas separated from the exhaust in the EGR is at a high temperature, often between 550°C and 650°C. If directly introduced into the engine cylinders, it would heat the engine's intake air, causing a decrease in intake air density and resulting in a smaller excess air coefficient λ, which cannot provide enough fresh air to the engine. Therefore, the exhaust gas separated by the EGR needs to be cooled. Utility Model Content

[0003] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0004] In view of the problems existing in the above-mentioned engine cooling systems, this utility model is proposed.

[0005] Therefore, the purpose of this utility model is to provide a diesel engine EGR cooling system to solve the problem that "the exhaust gas separated from the exhaust gas in the EGR is at a high temperature, often 550℃~650℃. If it is directly introduced into the engine cylinder, it will heat the engine intake air, causing a decrease in intake air density, resulting in a small excess air coefficient λ, which cannot provide enough fresh air to the engine."

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] A diesel engine EGR cooling system, comprising:

[0008] An engine body includes a water pump and an engine block, which are respectively mounted on the engine body and are interconnected. An EGR water intake pipe is fixedly mounted on the engine body and is connected to the engine block. An EGR water inlet hose is fixedly connected to the EGR water intake pipe. An EGR cooler is fixedly mounted on the engine body and is connected to the EGR cooler. An EGR valve seat is fixedly mounted on the engine body and has an EGR valve. The EGR cooler is fixedly connected to the EGR valve. An EGR return hose is fixedly connected to the EGR valve seat and is connected to the water pump. An exhaust manifold is fixedly mounted on the engine body and is fixedly connected to the EGR valve. An EGR pipe is fixedly connected to the EGR cooler, and an intake manifold is fixedly connected to the end of the EGR pipe. An intake manifold is fixedly connected to the intake manifold.

[0009] As a preferred embodiment of the diesel engine EGR cooling system of this utility model, the water pump is provided with an inlet and an outlet, and the outlet is connected to the engine body.

[0010] As a preferred embodiment of the diesel engine EGR cooling system of this utility model, the water pump is provided with an impeller, and the impeller is located at the center of the water pump.

[0011] As a preferred embodiment of the diesel engine EGR cooling system of this utility model, the engine body includes an engine body water jacket and an oil cooler mounting cavity. The engine body water jacket is connected to the oil cooler mounting cavity. The engine body water jacket is connected to the water outlet. The EGR water intake pipe is connected to the oil cooler mounting cavity.

[0012] As a preferred embodiment of the diesel engine EGR cooling system of this utility model, the EGR cooler has multiple fins on the intake side, and the fin spacing is ≤2.0mm.

[0013] The beneficial effects of this utility model are:

[0014] 1. After being pressurized by the water pump, the cooling water enters the engine block's water distribution jacket, flows through the oil cooler mounting cavity, and enters the EGR water intake pipe. At this point, the cooling water only partially cools the cylinder walls and engine oil, resulting in a small temperature rise. Simultaneously, there are no significant obstructions in between, and the cooling water pressure is not significantly reduced compared to when it first enters the engine block. That is, there is no significant pressure loss and no substantial temperature increase in the cooling water. The cooling water enters from the bottom of the EGR cooler, cools the EGR exhaust gas, and then exits from the top of the EGR cooler. This effectively removes gas from the EGR cooler and prevents vapor lock. Furthermore, the flow direction of the cooling water is opposite to that of the EGR exhaust gas, which, through thermal convection, more effectively reduces the temperature of the EGR exhaust gas.

[0015] 2. After exiting the cylinder, the EGR exhaust gas enters the EGR valve directly through the exhaust manifold. To prevent the EGR valve from overheating and sticking, coolant flows through the EGR valve, effectively cooling the EGR valve and its guide pipes.

[0016] 3. After cooling the EGR exhaust gas and EGR valve seat, the cooling water flows back to the low-pressure chamber of the water pump, and then enters the water distribution jacket of the machine body through the impeller in the water pump to form a circulation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them:

[0018] Figure 1 This is a frontal schematic diagram of the overall structure of a diesel engine EGR cooling system proposed in this utility model;

[0019] Figure 2 for Figure 1 The right view;

[0020] Figure 3 for Figure 2 The right view;

[0021] Figure 4 for Figure 3 The right view.

[0022] In the diagram: 100. Engine body; 1. Water pump; 1-1. Water inlet; 1-2. Water outlet; 2. Engine block; 2-1. Engine block water distribution jacket; 2-2. Oil cooler mounting cavity; 3. EGR water inlet pipe; 4. EGR water inlet hose; 5. EGR cooler; 6. EGR valve seat; 7. EGR water return hose; 8. Exhaust manifold; 9. EGR pipe; 10. Intake pipe; 11. Intake manifold; 12. EGR valve Detailed Implementation

[0023] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0026] Secondly, this utility model is described in detail with reference to the schematic diagrams. When describing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.

[0027] Reference Figure 1-4 This utility model provides a diesel engine EGR cooling system, comprising:

[0028] An engine body 100 includes a water pump 1 and an engine block 2. The water pump 1 and the engine block 2 are respectively mounted on the engine body 100 and are interconnected. An EGR water intake pipe 3 is fixedly mounted on the engine body 100 and is connected to the engine block 2. An EGR water inlet hose 4 is fixedly connected to the EGR water intake pipe 3. An EGR cooler 5 is fixedly mounted on the engine body 100, and the EGR water inlet hose 4 is connected to the EGR cooler 5. The EGR valve seat 6 is equipped with an EGR valve 12. The EGR cooler 5 is fixedly connected to the EGR valve 12. An EGR return hose 7 is fixedly connected to the EGR valve seat 6 and is connected to the water pump 1. An exhaust manifold 8 is fixedly installed on the engine body 100 and is fixedly connected to the EGR valve 12. An EGR pipe 9 is fixedly connected to the EGR cooler 5. An intake pipe 10 is fixedly connected to the end of the EGR pipe 9 and an intake manifold 11 is fixedly connected to the intake pipe 10.

[0029] The water pump 1 is equipped with an inlet 1-1 and an outlet 1-2. The outlet 1-2 is connected to the body 2, and the inlet 1-1 is connected to the water tank. Coolant is delivered into the water pump 1 through the inlet 1-1 and then into the body 2.

[0030] Furthermore, an impeller is installed inside the water pump 1, and the impeller is located at the center of the water pump 1. The impeller pressurizes the coolant and makes it flow.

[0031] Furthermore, the engine block 2 includes an engine block water jacket 2-1 and an oil cooler mounting cavity 2-2. The engine block water jacket 2-1 is connected to the oil cooler mounting cavity 2-2 and the engine block water jacket 2-1 is connected to the water outlet 1-2. The EGR water intake pipe 3 is connected to the oil cooler mounting cavity 2-2. The arrangement of the engine block water jacket 2-1 and the oil cooler mounting cavity 2-2 allows the coolant to cool the engine block 100 when it flows through the engine block water jacket 2-1 and the oil cooler mounting cavity 2-2.

[0032] Furthermore, the EGR cooler 5 has multiple fins on the intake side with a fin spacing of ≤2.0mm, which cool the exhaust gas.

[0033] During operation, coolant enters the water pump 1 from the vehicle's water tank through the inlet 1-1 of the water pump 1, and is pressurized by the impeller inside the water pump 1 before entering the engine block 2. It then flows through the engine block's water distribution jacket 2-1, through the integrated oil cooler mounting cavity 2-2, and into the EGR water intake pipe 3. The coolant only partially cools the cylinder walls and engine oil of the engine block 100. Subsequently, the coolant enters from the lower part of the EGR cooler 5, cools the EGR exhaust gas, and then enters the interior of the EGR valve seat 6, further cooling the EGR valve stem and guide pipe installed on the EGR valve seat 6. Finally, the coolant flows back to the low-pressure chamber of the water pump 1, and is then pressurized by the impeller of the water pump 1 before entering the engine block 2, forming a cycle.

[0034] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A diesel engine EGR cooling system, characterized in that: include: An engine body (100) includes a water pump (1) and an engine block (2). The water pump (1) and the engine block (2) are respectively mounted on the engine body (100) and are interconnected. An EGR water intake pipe (3) is fixedly mounted on the engine body (100) and is connected to the engine block (2). An EGR water inlet hose (4) is fixedly connected to the EGR water intake pipe (3). An EGR cooler (5) is fixedly mounted on the engine body (100) and is connected to the EGR cooler (5). An EGR valve is fixedly mounted on the engine body (100). The EGR valve seat (6) is provided with an EGR valve (12). The EGR cooler (5) is fixedly connected to the EGR valve (12). An EGR return hose (7) is fixedly connected to the EGR valve seat (6). The EGR return hose (7) is connected to the water pump (1). An exhaust manifold (8) is fixedly provided on the engine body (100). The exhaust manifold (8) is fixedly connected to the EGR valve (12). An EGR pipe (9) is fixedly connected to the EGR cooler (5). An intake pipe (10) is fixedly connected to the end of the EGR pipe (9). An intake manifold (11) is fixedly connected to the intake pipe (10).

2. The diesel engine EGR cooling system according to claim 1, characterized in that: The water pump (1) is provided with an inlet (1-1) and an outlet (1-2), and the outlet (1-2) is connected to the body (2).

3. The diesel engine EGR cooling system according to claim 2, characterized in that: The water pump (1) is equipped with an impeller, which is located at the center of the water pump (1).

4. The diesel engine EGR cooling system according to claim 3, characterized in that: The body (2) includes a body water distribution jacket (2-1) and an oil cooler mounting cavity (2-2). The body water distribution jacket (2-1) is connected to the oil cooler mounting cavity (2-2). The body water distribution jacket (2-1) is connected to the water outlet (1-2). The EGR water intake pipe (3) is connected to the oil cooler mounting cavity (2-2).

5. A diesel engine EGR cooling system according to claim 4, characterized in that: The EGR cooler (5) has multiple fins on the air intake side, with a fin spacing of ≤2.0mm.

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