A marine diesel engine cooling system

Abstract

A marine diesel engine cooling system relates to the technical field of diesel engine cooling equipment, and comprises a filtering device and a cooling device, wherein the water inlet of the filtering device is communicated with seawater outside; the cooling device comprises a freezing tank, a pre-cooling tank and a mixing tank; the freezing tank is communicated with the water outlet of the filtering device, the freezing tank is used for freezing part of filtered seawater and making ice chips, and the ice chip discharge outlet of the freezing tank is communicated with the mixing tank; the pre-cooling tank is communicated with the water outlet of the filtering device, the pre-cooling tank is used for cooling the remaining filtered seawater, and the water outlet of the pre-cooling tank is communicated with the mixing tank; the water outlet of the mixing tank is communicated with a diesel engine cooling tank, and the water outlet of the diesel engine cooling tank is communicated with the filtering device. The application can mix the ice chips and the pre-cooled seawater to form a low-temperature cooling medium, adopt a closed cycle to completely avoid seawater evaporation and scaling, automatically remove impurities by integrating a self-cleaning filter, and significantly improve the cooling efficiency and system reliability.

Description

Technical Field

[0001] This invention relates to the field of diesel engine cooling equipment technology, and more particularly to a marine diesel engine cooling system. Background Technology

[0002] Marine diesel engines are hailed as the "heart" of a ship, and their operational stability and efficiency directly determine the overall power performance and reliability of the vessel. A highly efficient cooling system is crucial for maintaining optimal operating conditions. Currently, closed-loop central cooling systems are widely adopted as the mainstream technology in the marine industry. The core of this system lies in the collaborative function of two independent circulation loops: the internal loop uses clean fresh water to circulate and cool the diesel engine and its auxiliary equipment—such as the air cooler, oil cooler, and cylinder liner water cooler; the external loop introduces seawater, which cools the fresh water in the internal loop through plate or shell-and-tube heat exchangers, thus achieving heat exchange.

[0003] Although the closed-loop design has significantly improved corrosion and scale resistance compared to earlier open-loop direct-cooling seawater systems, effectively protecting the core components of the diesel engine, its seawater circuit still faces two major technical challenges: First, the problem of clogging caused by seawater impurities. Seawater contains a large amount of suspended solids, microorganisms and their larvae, which easily accumulate in the seawater filter and heat exchanger channels, leading to reduced flow capacity and requiring frequent system shutdowns for manual cleaning or filter replacement. This process is not only cumbersome and costly to maintain, but also reduces the continuity and economy of ship operations. Second, the more persistent problem of seawater scaling. Despite using indirect heat exchange, seawater is still heated as it flows through the heat exchanger, causing dissolved calcium, magnesium, and other salts to precipitate and adhere firmly to the heat exchange surface, forming hard scale with extremely poor thermal conductivity. Scale not only significantly reduces heat transfer efficiency, causing insufficient cooling or even overheating of the diesel engine, but also reduces the flow cross-section and increases water flow resistance, further affecting system performance. Current countermeasures mainly include adding chemical agents to inhibit scale formation and periodically shutting down the machine for mechanical or acid washing to remove scale. However, these methods are either unsustainable due to the cost of the agents and environmental issues, or passive due to the high intensity of the work and the impact on operations. None of them can fundamentally prevent the occurrence of scale formation. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide a marine diesel engine cooling system that can mix ice chips with pre-cooled seawater to form a low-temperature cooling medium, adopt a closed-loop circulation to completely avoid seawater evaporation and scaling, and integrate a self-cleaning filter to automatically remove impurities, thereby significantly improving cooling efficiency and system reliability.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0006] A marine diesel engine cooling system, comprising:

[0007] A filtration device, wherein the inlet of the filtration device is connected to the outside seawater;

[0008] A cooling device includes a freezing chamber, a precooling chamber, and a mixing chamber. The freezing chamber is connected to the outlet of the filtration device and is used to freeze a portion of the filtered seawater to form ice chips. The ice chip outlet of the freezing chamber is connected to the mixing chamber. The precooling chamber is connected to the outlet of the filtration device and is used to cool the remaining filtered seawater. The outlet of the precooling chamber is connected to the mixing chamber. The outlet of the mixing chamber is connected to a diesel engine cooling chamber, and the outlet of the diesel engine cooling chamber is connected to the filtration device.

[0009] Preferably, the filtration device includes a filter box, and the inlet of the filter box is connected to the outside seawater through a connecting pipe.

[0010] The filter box includes a filter box body, a filter screen is fixed inside the filter box body, one side of the filter screen is inclined downwards, a sealing block is provided below the filter screen, the sealing block can slide back and forth vertically, the top surface of the sealing block is inclined and the same as the inclined direction and angle of the filter screen, and a drain pipe connected to the outside is installed on the filter box body.

[0011] The bottom of the sealing block is connected to the drive end of the sealing power component via a top rod.

[0012] Preferably, the outlet of the diesel engine cooling box is connected to the filter box and located above the filter screen, and the drain pipe is located near the bottom inclined end of the filter screen;

[0013] A seawater filter is installed on the connecting pipe.

[0014] Preferably, the freezer includes a freezer body, and the interior of the freezer body is provided with a water injection mechanism, an ice making mechanism, and an ice crushing mechanism;

[0015] The water injection mechanism includes a U-shaped water injection frame, which can reciprocate in the horizontal direction. The U-shaped water injection frame is horizontally arranged and its opening faces the ice-making mechanism. A water injection channel is provided on the U-shaped water injection frame, which connects the inner cavity of the U-shaped water injection frame to one end of the connecting pipe two, and the other end of the connecting pipe two is connected to the water outlet of the filter device.

[0016] The ice-making mechanism includes a vertically fixed ice-making tube with openings at both ends. A ring-shaped liquid nitrogen tank is fixed to the outer wall of the ice-making tube and is connected to an external liquid nitrogen replenishment device. During water injection, a U-shaped water injection frame covers both ends of the ice-making tube, and the water injection channel connects the connecting pipe to the inner cavity of the ice-making tube. After ice is made, the U-shaped water injection frame moves horizontally and fully exposes the ice-making tube. A pushing mechanism is provided above the ice-making tube to push the ice out of the ice-making tube.

[0017] The ice-crushing mechanism is located below the ice-making tube. The ice-crushing mechanism includes two opposing crushing plates that can move closer to or further away from each other, forming an ice-crushing area between the two crushing plates. A conveying auger is installed below the two crushing plates to push the ice chips generated by the crushing process to the mixing box.

[0018] Preferably, the U-shaped water injection frame includes a top plate, a bottom plate, and a side plate connecting the two. The water injection channel is opened on the top plate, and a transition hose is connected between the water injection channel and the second connecting pipe.

[0019] A translation motor is installed on the side plate. The output shaft of the translation motor passes through the side plate and is connected to a horizontally arranged lead screw. The lead screw is adapted to a nut installed on a translation bracket. The translation bracket is fixedly installed inside the freezer body.

[0020] A horizontally arranged guide rod is installed on the side plate, and the guide rod passes through the translation bracket.

[0021] Preferably, the pushing mechanism includes an electric telescopic rod fixed inside the freezer, the electric telescopic rod being vertically arranged with its actuating end facing the ice-making tube, and a push plate being installed on the actuating end of the electric telescopic rod;

[0022] The pusher plate is a circular plate and is coaxially arranged with the ice-making tube.

[0023] Preferably, the ice-crushing mechanism includes a conveyor frame, the conveyor frame having a U-shaped cross-section with the opening facing upwards, and the two crushing plates are respectively installed on the two side walls of the conveyor frame;

[0024] A crushing hydraulic cylinder corresponding to the crushing plate is installed on the side wall of the conveyor frame. The actuating end of the crushing hydraulic cylinder is connected to the U-shaped push rod, and both ends of the U-shaped push rod are connected to the crushing plate.

[0025] The bottom of the conveyor frame is equipped with the transfer auger, and a screen is provided between the transfer auger and the two crushing plates. The screen is horizontally installed between the two side walls of the conveyor frame. One end of the transfer auger extends out of the conveyor frame and is powered by the transfer motor. The transfer auger pushes the ice chips generated by the crushing to the mixing box.

[0026] Preferably, the top of the crushing plate is provided with an outwardly inclined guide portion, and the inner wall of the crushing plate is provided with a plurality of anti-slip protrusions.

[0027] An inclined chute connects the conveyor frame and the mixing box. The chute is a closed chute, with its top end positioned near the other end of the conveying auger. The conveying auger pushes the ice chips generated from the crushing process into the chute, and the ice chips entering the chute are then slid into the mixing box.

[0028] Preferably, the precooling box includes a precooling box body, which is connected to the freezing box, and the gas temperature inside the freezing box is lower than the gas temperature inside the precooling box body;

[0029] The precooling chamber is fixedly equipped with a partition, which divides the inner cavity of the precooling chamber into an independent air blowing chamber and a precooling chamber; a fan is installed in the air blowing chamber, and the fan is connected to the freezer through an air-cooling pipe;

[0030] The precooling chamber is equipped with two air guide pipes and one cooling pipe. The two air guide pipes are arranged perpendicular to the partition. One end of each air guide pipe is open and located inside the blower chamber. Several air outlets are provided on each air guide pipe, and the air outlets on the two air guide pipes are arranged opposite to each other. The cooling pipe is installed between the two air guide pipes. The cooling pipe has an S-shaped structure. The water inlet of the cooling pipe is connected to the water outlet of the filter device through a connecting pipe 3. The water outlet of the cooling pipe is connected to the mixing box.

[0031] Preferably, the mixing chamber includes a mixing chamber body, a stirring shaft is rotatably mounted inside the mixing chamber body, one end of the stirring shaft is poweredly connected to a stirring motor, and a plurality of stirring blades are mounted on the stirring shaft along its axial direction;

[0032] The inner cavity of the mixing chamber is connected to the freezing chamber, and the inner cavity of the mixing chamber is connected to the precooling chamber through connecting pipe four. The ice chips produced by the freezing chamber are mixed with the seawater cooled by the precooling chamber in the mixing chamber. The inner cavity of the mixing chamber is connected to the diesel engine cooling chamber through connecting pipe five, and the diesel engine cooling chamber is connected to the filter device through connecting pipe six.

[0033] After adopting the above technical solution, the beneficial effects of the present invention are:

[0034] The marine diesel engine cooling system of this application includes a filtration device and a cooling device. The inlet of the filtration device is connected to the outside seawater. The cooling device includes a freezing tank, a pre-cooling tank, and a mixing tank. The freezing tank is connected to the outlet of the filtration device and is used to freeze a portion of the filtered seawater into ice chips. The ice chip outlet of the freezing tank is connected to the mixing tank. The pre-cooling tank is connected to the outlet of the filtration device and is used to cool the remaining filtered seawater. The outlet of the pre-cooling tank is connected to the mixing tank. The outlet of the mixing tank is connected to the diesel engine cooling tank, and the outlet of the diesel engine cooling tank is connected to the filtration device. After preliminary purification by the seawater filtration device, the seawater is divided into two streams. One stream enters the freezing tank to be made into ice chips; the other stream enters the pre-cooling tank for preliminary cooling. Subsequently, the ice chips and pre-cooled seawater are thoroughly mixed in the mixing tank to form a low-temperature ice-water mixture. This mixture is transported to the diesel engine cooling tank for efficient cooling of the diesel engine. After absorbing heat, it flows back to the seawater filtration device, forming a complete closed-loop cycle, thereby preventing seawater evaporation and scaling, and improving cooling efficiency.

[0035] In this application, seawater is converted into ice chips and mixed with pre-cooled seawater to form a low-temperature cooling medium. This medium circulates in a closed loop, avoiding the evaporation process of seawater. Dissolved minerals in the seawater cannot be concentrated and precipitated, thus preventing scale formation at its source. This process eliminates scale adhesion to heat exchange surfaces, ensuring long-term stable operation of the system. Secondly, before entering the circulation, the seawater is filtered to remove suspended impurities. In the subsequent ice-making stage, impurities dissolved in the water are separated during phase change and retained in the ice-making unit. This improves the purity of the cooling medium ultimately participating in the circulation. This system achieves continuous purification of the medium through physical means, reducing the probability of flow channel blockage. Finally, when the ice chips melt in the diesel engine cooling box, they absorb the latent heat of phase change. Their cooling capacity per unit mass exceeds that of traditional sensible heat cooling methods. Therefore, this application can achieve the required cooling effect with a smaller medium flow rate or lower operating temperature, reducing the demand on pumping power and providing more stable thermal management conditions for the diesel engine. Attached Figure Description

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] Figure 1 This is a schematic diagram of the structure of the marine diesel engine cooling system according to an embodiment of the present invention;

[0038] Figure 2 yes Figure 1 A schematic diagram of the structure of the intermediate filtration device;

[0039] Figure 3 yes Figure 1 Schematic diagram of the structure of the intermediate freezer;

[0040] Figure 4 yes Figure 3 Enlarged view of part A;

[0041] Figure 5 yes Figure 3 Schematic diagram of the ice-crushing mechanism;

[0042] Figure 6 yes Figure 1 Schematic diagram of the precooling box;

[0043] Figure 7 yes Figure 1 Schematic diagram of the structure of the mixing chamber;

[0044] In the picture:

[0045] 1. Filter device; 11. Filter box; 12. Connecting pipe 1; 13. Filter screen; 14. Sealing block; 15. Drain pipe; 16. Top rod; 17. Sealing power component; 18. Seawater filter;

[0046] 2. Cooling device;

[0047] 3. Freezer; 31. Water injection mechanism; 311. U-shaped water injection rack; 3111. Top plate; 3112. Bottom plate; 3113. Side plate; 312. Water injection channel; 313. Connecting pipe two; 314. Transition hose; 315. Translation motor; 316. Lead screw; 317. Translation bracket; 318. Nut; 319. Guide rod;

[0048] 32. Ice-making mechanism; 321. Ice-making pipe; 322. Liquid nitrogen tank;

[0049] 33. Ice crushing mechanism; 331. Crushing plate; 3311. Guide section; 3312. Anti-slip protrusion; 332. Transfer auger; 333. Conveyor frame; 334. Crushing hydraulic cylinder; 335. U-shaped push rod; 336. Screen; 337. Transfer motor; 338. Chute;

[0050] 34. Pushing mechanism; 341. Electric telescopic rod; 342. Push plate;

[0051] 4. Precooling box; 41. Partition; 42. Fan; 43. Air-cooled pipe; 44. Air duct; 441. Air outlet; 45. Cooling pipe; 451. Connecting pipe III;

[0052] 5. Mixing box; 51. Stirring shaft; 52. Stirring motor; 53. Stirring blades; 54. Connecting pipe four; 55. Connecting pipe five;

[0053] 6. Diesel engine cooling box; 61. Connecting pipe six. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0055] like Figure 1 As shown, the present invention includes a filtration device 1 and a cooling device 2. The inlet of the filtration device 1 is connected to external seawater. The cooling device 2 includes a freezing chamber 3, a precooling chamber 4, and a mixing chamber 5. The freezing chamber 3 is connected to the outlet of the filtration device 1 and is used to freeze a portion of the filtered seawater to form ice chips. The ice chip outlet of the freezing chamber 3 is connected to the mixing chamber 5. The precooling chamber 4 is connected to the outlet of the filtration device 1 and is used to cool the remaining filtered seawater. The outlet of the precooling chamber 4 is connected to the mixing chamber 5. The outlet of the mixing chamber 5 is connected to a diesel engine cooling chamber 6, and the outlet of the diesel engine cooling chamber 6 is connected to the filtration device 1.

[0056] In this application, seawater first enters the system through the inlet of filter device 1. Filter device 1 performs preliminary purification of the seawater, removing suspended particles, aquatic organisms, and other impurities, providing a relatively clean water source for the subsequent cooling process. The filtered seawater is divided into two branches at the outlet of filter device 1. One branch enters the freezing chamber 3, where it is frozen into a solid state and then crushed into fine ice chips. The other branch enters the pre-cooling chamber 4, where the seawater temperature is lowered to achieve a pre-cooling effect. The prepared ice chips are discharged from the outlet of the freezing chamber 3, and then discharged from the pre-cooling chamber 4. The low-temperature seawater discharged from cold box 4 enters mixing box 5 together with the cold seawater. In mixing box 5, ice chips and low-temperature seawater are thoroughly mixed to form a homogeneous ice-water mixture. This mixture has a temperature characteristic significantly lower than that of room-temperature seawater. The low-temperature ice-water mixture generated in mixing box 5 is then transported to diesel engine cooling box 6, where it exchanges heat with the existing freshwater cooling system, absorbing the heat generated by the diesel engine and cooling it down. During this process, the ice chips undergo a phase change and melt, absorbing a large amount of latent heat, thus significantly improving cooling efficiency. After heat exchange, the water medium returns from the outlet of diesel engine cooling box 6 to filter device 1, re-entering the treatment cycle. This process forms a complete closed-loop cooling circuit, not only realizing the recycling of the cooling medium but also avoiding the mineral scaling problem caused by seawater evaporation and concentration, while ensuring continuous and stable cooling performance.

[0057] like Figure 1 , Figure 2As shown in the present application, the filtration device 1 includes a filter box 11, the inlet of which is connected to the outside seawater through a connecting pipe 12; the filter box 11 includes a filter body, a filter screen 13 is fixed inside the filter body, one side of the filter screen 13 is inclined downwards, a blocking block 14 is provided below the filter screen 13, the blocking block 14 can slide back and forth vertically, the top surface of the blocking block 14 is inclined and the same as the inclination direction and inclination angle of the filter screen 13, a drain pipe 15 connected to the outside is installed on the filter body; the bottom of the blocking block 14 is connected to the drive end of the blocking power component 17 through a top rod 16.

[0058] Before cooling, the seawater is first filtered. The seawater enters the filter chamber through the connecting pipe 12, and the water flows through the inclined filter screen 13. Suspended impurities are trapped by the filter screen 13 and fall down and accumulate along the inclined surface. The filtered clean water enters the other side of the chamber through the filter screen 13 and flows to the cooling device 2 through the outlet. Secondly, after multiple cycles, a large amount of suspended impurities are trapped and accumulated by the filter screen 13, so the filter screen 13 needs to be cleaned. When cleaning is required, first close the valves of each pipeline, and the sealing power component 17 pushes the sealing block 14 upward through the push rod 16, so that its top surface is tightly attached to the lower surface of the filter screen 13, blocking the clean water channel. At this time, water continues to enter the tank, flushing the filter screen 13 and carrying the trapped impurities out of the system through the drain pipe 15, completing the automatic cleaning; or, the sealing power component 17 pushes the sealing block 14 upward through the push rod 16, so that its top surface is close to the lower surface of the filter screen 13, and then water continues to enter the tank. The water level rises and forms reverse pressure, forcing the water flow to reverse through the filter screen 13, which can also complete the flushing of the filter screen 13.

[0059] Preferably, the sealing power component 17 is a hydraulic cylinder.

[0060] The outlet of the diesel engine cooling box 6 is connected to the filter box and located above the filter screen 13. The drain pipe 15 is positioned near the bottom of the inclined section of the filter screen 13. A seawater filter 18 is installed on the connecting pipe 12. The outlet of the diesel engine cooling box 6 is connected to the filter box and located above the filter screen 13, allowing the return hot water after heat exchange to directly flush the upper surface of the filter screen 13. The hot water can dissolve some grease and impurities, preventing blockage. The drain pipe 15 is positioned near the bottom of the inclined section of the filter screen 13. This arrangement conforms to the principle that impurities naturally fall due to gravity, ensuring that impurities washed away by the water flow can be quickly discharged from the system with the shortest path and least resistance during flushing, greatly improving the sewage discharge efficiency and avoiding secondary deposition of impurities in the box.

[0061] The seawater filter 18 installed on the connecting pipe 12 constitutes the pre-filter unit of this application. It can pre-filter out larger suspended solids and fibrous impurities before the seawater enters the main filtration system, which significantly reduces the filtration load on the downstream filter screen 13, extends its continuous working time, and reduces the rinsing frequency, thereby improving the stability and economy of the entire system operation.

[0062] like Figure 1 , Figures 3 to 5 As shown in the present application, the freezer 3 includes a freezer body, and the freezer body is provided with a water injection mechanism 31, an ice-making mechanism 32, and an ice-crushing mechanism 33. The water injection mechanism 31 is used to inject seawater into the ice-making mechanism 32, the ice-making mechanism 32 is used to freeze the seawater to make ice, and the ice-crushing mechanism 33 is used to crush the made ice into ice chips.

[0063] The water injection mechanism 31 includes a U-shaped water injection frame 311, which can reciprocate horizontally. The U-shaped water injection frame 311 is horizontally positioned with its opening facing the ice-making mechanism 32. A water injection channel 312 is provided on the U-shaped water injection frame 311, which connects the inner cavity of the U-shaped water injection frame 311 to one end of the connecting pipe 313. The other end of the connecting pipe 313 is connected to the outlet of the filter device 1. When ice is needed, water must first be injected. The U-shaped water injection frame 311 moves horizontally to the working position, so that its open end completely covers the upper and lower ends of the ice-making tube 321, forming a sealed water injection space. Then, some seawater from the filter device 1 is injected into the ice-making tube 321 through the connecting pipe 313 and the water injection channel 312, thus completing the water injection.

[0064] The ice-making mechanism 32 includes a vertically fixed ice-making tube 321 with openings at both ends. A ring-shaped liquid nitrogen tank 322 is fixed to the outer wall of the ice-making tube 321, and the liquid nitrogen tank 322 is connected to an external liquid nitrogen replenishment device. During water injection and ice making, a U-shaped water injection frame 311 covers both ends of the ice-making tube 321, and the water injection channel 312 connects the connecting pipe 313 to the inner cavity of the ice-making tube 321. After ice making, the U-shaped water injection frame 311 moves horizontally and fully exposes the ice-making tube 321. A pushing mechanism 34 is provided above the ice-making tube 321. 4 is used to push the ice out of the ice-making tube 321; when the ice-making tube 321 is filled with seawater, the liquid nitrogen circulating in the liquid nitrogen tank 322 begins to rapidly cool the ice-making tube 321, causing the seawater inside to freeze and solidify quickly, forming an integral ice column that fits the shape of the tube wall. After the ice-making is completed, the U-shaped water injection rack 311 moves horizontally back to its original position, completely exposing the ice-making tube 321, making room for the de-icing process. The pushing mechanism 34 above starts to work, pushing the solidified ice column out of the ice-making tube 321 completely, allowing it to fall naturally to the ice-crushing mechanism 33 below under the action of gravity.

[0065] The ice-crushing mechanism 33 is located below the ice-making tube 321. The ice-crushing mechanism 33 includes two opposing crushing plates 331. The two crushing plates 331 can move closer or further apart from each other, forming an ice-crushing area between the two crushing plates 331. A transfer auger 332 is installed below the two crushing plates 331. The transfer auger 332 is used to push the ice chips generated by crushing to the mixing box 5. The falling ice column first falls between the two opposing crushing plates 331. The two crushing plates 331 move back and forth in opposite directions, squeezing and crushing the ice column. The falling ice chips are captured by the rotating transfer auger 332 and transported forward, and finally evenly pushed into the mixing box 5 to wait for subsequent mixing and use.

[0066] In this application, the U-shaped water injection rack 311 includes a top plate 3111, a bottom plate 3112, and a side plate 3113 connecting the two. A water injection channel 312 is opened on the top plate 3111, and a transition hose 314 is connected between the water injection channel 312 and the connecting pipe 313. A translation motor 315 is installed on the side plate 3113. The output shaft of the translation motor 315 passes through the side plate 3113 and is connected to a horizontally arranged lead screw 316. The lead screw 316 is adapted to a nut 318 installed on a translation bracket 317. The translation bracket 317 is fixedly installed inside the freezer. A horizontally arranged guide rod 319 is installed on the side plate 3113 and passes through the translation bracket 317.

[0067] The pushing mechanism 34 includes an electric telescopic rod 341 fixed inside the freezer. The electric telescopic rod 341 is vertically arranged with its actuating end facing the ice-making tube 321. A push plate 342 is installed on the actuating end of the electric telescopic rod 341. The push plate 342 is a circular plate and is coaxially arranged with the ice-making tube 321. After receiving a command, the electric telescopic rod 341 extends downward, driving the connected disc-shaped push plate 342 to move vertically. Since the push plate 342 is coaxial with the ice-making tube 321, it can accurately and evenly contact the entire top surface of the ice column. Under the continuous pushing of the electric telescopic rod 341, the push plate 342 smoothly and completely pushes the ice column out of the ice-making tube 321. Under the action of gravity, the ice column falls from the lower opening of the ice-making tube 321 and enters the crushing area of ​​the ice crushing mechanism 33 directly below it, preparing for the subsequent crushing process.

[0068] The ice crushing mechanism 33 includes a conveyor frame 333, which has a U-shaped cross-section with the opening facing upwards. Two crushing plates 331 are respectively installed on the two side walls of the conveyor frame 333. A crushing hydraulic cylinder 334 corresponding to the crushing plate 331 is installed on the side wall of the conveyor frame 333. The actuating end of the crushing hydraulic cylinder 334 is connected to a U-shaped push rod 335. Both ends of the U-shaped push rod 335 are connected to the crushing plate 331. A transfer auger 332 is installed at the bottom of the conveyor frame 333. A screen 336 is set between the transfer auger 332 and the two crushing plates 331. The screen 336 is horizontally installed between the two side walls of the conveyor frame 333. One end of the transfer auger 332 extends out of the conveyor frame 333 and is powered by a transfer motor 337. The transfer auger 332 pushes the ice chips generated by crushing to the mixing box 5.

[0069] When ice blocks fall between two opposing crushing plates 331, the crushing hydraulic cylinder 334 starts working. Its actuating end drives the two crushing plates 331 to reciprocate in opposite directions via a U-shaped push rod 335, repeatedly squeezing the ice blocks and crushing them into small pieces. The crushed ice falls onto the screen 336 below. Fine ice chips that meet the size requirements fall through the mesh of the screen 336, while larger ice blocks remain on the screen 336 and continue to be crushed again by the crushing plates 331 until they meet the size requirements and can pass through the screen. The qualified ice chips that pass through the screen 336 fall to the bottom of the conveyor frame 333 and are captured by the rotating conveying auger 332. Driven by the conveying motor 337, the auger blades continue to rotate, pushing the ice chips forward along the axial direction of the conveyor frame 333 and evenly conveying them to the mixing box 5, completing the entire process of ice crushing and conveying.

[0070] Preferably, the top of the crushing plate 331 is provided with an outwardly inclined guide portion 3311, and the inner wall of the crushing plate 331 is provided with a plurality of anti-slip protrusions 3312; an inclined chute 338 is connected between the conveyor frame 333 and the mixing box 5. The chute 338 is a closed chute, and the top of the chute 338 is located near the other end of the transfer auger 332. The transfer auger 332 pushes the ice chips generated by crushing into the chute 338, and the ice chips entering the chute 338 are slid into the mixing box 5. The guide portion 3311 receives the falling ice blocks and guides them into the crushing area between the two crushing plates 331, preventing the ice blocks from getting stuck on the top of the crushing plate 331 or the edge of the conveyor frame 333. The anti-slip protrusions 3312 increase the friction between the inner wall of the crushing plate 331 and the ice blocks, preventing the ice blocks from slipping or rotating when compressed, so that the crushing force acts more effectively on the ice blocks and improves the crushing efficiency. The chute 338 is inclined and positioned between the conveyor frame 333 and the mixing box 5. This enclosed structure utilizes gravity to transport ice chips, reducing energy consumption during transport; it also isolates the exchange of internal and external air to prevent cold loss; and it provides a centralized and directional transport path for the ice chips, ensuring their accurate entry into the mixing box 5.

[0071] like Figure 1 , Figure 6 As shown in the present application, the precooling box 4 includes a precooling box body, which is connected to the freezing box 3. The gas temperature inside the freezing box 3 is lower than the gas temperature inside the precooling box body. A partition 41 is fixedly installed inside the precooling box body, which divides the inner cavity of the precooling box body into an independent blowing chamber and a precooling chamber. A fan 42 is installed in the blowing chamber, and the fan 42 is connected to the freezing box 3 through an air-cooling pipe 43. Two air guide pipes 44 and one cooling pipe 45 are installed in the precooling chamber. The two air guide pipes 44 are arranged perpendicular to the partition 41. One end of the air guide pipe 44 is open and located in the blowing chamber. Several air outlets 441 are opened on the air guide pipes 44, and the air outlets 441 on the two air guide pipes 44 are arranged opposite to each other. The cooling pipe 45 is installed between the two air guide pipes 44. The cooling pipe 45 has an S-shaped structure. The water inlet of the cooling pipe 45 is connected to the water outlet of the filter device 1 through a connecting pipe 451, and the water outlet of the cooling pipe 45 is connected to the mixing box 5.

[0072] The blower 42 draws low-temperature gas from the freezer 3 through the air-cooled pipe 43 and sends it into the blower chamber formed by the partition 41. The low-temperature gas enters the two air guide pipes 44 in the blower chamber and is evenly sprayed out through the air outlets 441 arranged opposite to each other on the pipe wall, forming a uniform low-temperature air curtain in the pre-cooling chamber. At the same time, seawater from the filter device 1 flows into the pre-cooling chamber through the connecting pipe 451 and the cooling pipes 45 arranged in an S-shape. As the seawater flows through the cooling pipes 45, its heat is fully exchanged with the low-temperature air curtain through the pipe wall, thereby achieving cooling. The cooled seawater finally flows out from the outlet of the cooling pipes 45 and enters the mixing box 5.

[0073] In this structure, the low-temperature exhaust gas from the refrigeration box 3 is recovered and utilized through the fan 42 and the air-cooled pipe 43, realizing the secondary utilization of the system's cooling capacity and significantly reducing energy consumption. The structure of the air duct 44 and its corresponding air outlet 441 can form a uniform and stable cooling air field, ensuring uniform heat exchange in all parts of the S-shaped cooling pipe 45 and effectively improving heat exchange efficiency. The S-shaped tortuous arrangement of the cooling pipe 45 greatly increases the effective heat exchange area, allowing seawater to fully exchange heat with the low-temperature air, thereby achieving efficient pre-cooling of seawater in a limited space.

[0074] like Figure 1 , Figure 7As shown, the mixing tank 5 includes a mixing tank body, in which a stirring shaft 51 is rotatably mounted. One end of the stirring shaft 51 is powered by a stirring motor 52. Several stirring blades 53 are mounted on the stirring shaft 51 along its axial direction. The inner cavity of the mixing tank body is connected to the freezing tank 3. The inner cavity of the mixing tank body is connected to the precooling tank 4 through a connecting pipe 54. The ice chips produced in the freezing tank 3 are mixed with the seawater cooled in the precooling tank 4 in the mixing tank body. The inner cavity of the mixing tank body is connected to the diesel engine cooling tank 6 through a connecting pipe 55. The diesel engine cooling tank 6 is connected to the filter device 1 through a connecting pipe 61.

[0075] Ice chips produced in the freezing chamber 3 and seawater cooled in the pre-cooling chamber 4 enter the mixing chamber separately. The stirring motor 52 drives the stirring shaft 51 and stirring blades 53 to rotate, so that the ice chips and seawater are fully mixed to form a uniform low-temperature medium, preventing the ice chips from clumping. This medium enters the diesel engine cooling chamber 6 through the connecting pipe 55, completes heat exchange, and then becomes return water, returning to the filter device 1 through the connecting pipe 61. This process achieves uniform mixing and closed-loop circulation of the medium, which not only improves cooling efficiency but also fundamentally eliminates the problem of scaling.

[0076] The working process of this application is as follows: Seawater first passes through seawater filter 18 for coarse filtration and then enters filter box 11. The water flows through inclined filter screen 13, and impurities are intercepted. The filtered clean water is divided into two paths: one path enters freezer 3 through connecting pipe 2 313, and the other path enters precooling box 4 through connecting pipe 3 451.

[0077] In the freezer 3, the U-shaped water injection frame 311 of the water injection mechanism 31 moves to the upper and lower ends of the ice-making tube 321 to form a sealed space, and seawater is injected. After the liquid nitrogen tank 322 cools the ice-making tube 321, the seawater inside forms an ice column. The U-shaped water injection frame 311 is retracted, and the pushing mechanism 34 pushes the ice column to the ice crushing mechanism 33. The crushing plate 331 squeezes and crushes the ice block. The qualified ice chips are sent to the mixing tank 5 through the chute 338 by the transfer auger 332 via the screen 336.

[0078] In the precooling box 4, the fan 42 introduces the low-temperature gas from the refrigeration box 3 through the air-cooling pipe 43, and forms a uniform air curtain through the air outlet 441 of the air duct 44. The seawater flowing through the S-shaped cooling pipe 45 exchanges heat with the air curtain and is cooled down, and then enters the mixing box 5.

[0079] Inside the mixing tank 5, the stirring mechanism mixes ice chips and low-temperature seawater into a uniform low-temperature medium, which enters the diesel engine cooling tank 6 through connecting pipe 55. In the diesel engine cooling tank 6, this medium exchanges heat with the freshwater cooling system, absorbing heat. The melting ice chips absorb a large amount of latent heat, significantly improving cooling efficiency. The water, after absorbing heat, returns to the filter device 1 through connecting pipe 61, forming a complete closed-loop cycle. This cycle not only achieves the reuse of the cooling medium but also fundamentally avoids the evaporation and concentration of seawater, completely solving the problems of scaling and clogging.

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A marine diesel engine cooling system, characterized in that, include: A filter device (1) is provided, wherein the inlet of the filter device (1) is connected to the outside seawater. Cooling device (2), the cooling device (2) includes a freezing box (3), a precooling box (4) and a mixing box (5); the freezing box (3) is connected to the outlet of the filter device (1), the freezing box (3) is used to freeze part of the filtered seawater and make ice chips, and the ice chip outlet of the freezing box (3) is connected to the mixing box (5); the precooling box (4) is connected to the outlet of the filter device (1), the precooling box (4) is used to cool the remaining filtered seawater, and the outlet of the precooling box (4) is connected to the mixing box (5); the outlet of the mixing box (5) is connected to the diesel engine cooling box (6), and the outlet of the diesel engine cooling box (6) is connected to the filter device (1); The filtration device (1) includes a filter box (11), the inlet of which is connected to the outside seawater through a connecting pipe (12); the filter box (11) includes a filter box body, a filter screen (13) is fixed inside the filter box body, and the outlet of the diesel engine cooling box (6) is connected to the filter box body and located above the filter screen (13). The freezer (3) includes a freezer body, inside which are provided a water injection mechanism (31), an ice-making mechanism (32), and an ice-crushing mechanism (33); the water injection mechanism (31) includes a U-shaped water injection rack (311), which can reciprocate horizontally, and a water injection channel (312) is provided on the U-shaped water injection rack (311), which connects the inner cavity of the U-shaped water injection rack (311) to one end of a connecting pipe (313), and the other end of the connecting pipe (313) is connected to the outlet of the filter device (1); the ice-making mechanism (32) includes a vertically fixed An ice-making tube (321) is provided, with openings at both ends. A ring-shaped liquid nitrogen tank (322) is fixed on the outer wall of the ice-making tube (321). During water injection and ice making, the U-shaped water injection rack (311) covers both ends of the ice-making tube (321), and the water injection channel (312) connects the connecting pipe (313) to the inner cavity of the ice-making tube (321). The ice-crushing mechanism (33) is located below the ice-making tube (321). The ice-crushing mechanism (33) includes two opposing crushing plates (331), and a conveying auger (332) is installed below the two crushing plates (331). The U-shaped water injection rack (311) includes a top plate (3111), a bottom plate (3112), and a side plate (3113) connecting the two. The water injection channel (312) is opened on the top plate (3111), and a transition hose (314) is connected between the water injection channel (312) and the connecting pipe (313). A translation motor (315) is installed on the side plate (3113), and the output shaft of the translation motor (315) passes through the side plate (3113) and is connected to a horizontally arranged lead screw (316). The lead screw (316) is adapted to a nut (318) installed on a translation bracket (317). The translation bracket (317) is fixedly installed inside the freezer. A horizontally arranged guide rod (319) is installed on the side plate (3113), and the guide rod (319) passes through the translation bracket (317).

2. The marine diesel engine cooling system as described in claim 1, characterized in that, The filter screen (13) is inclined downward on one side, and a sealing block (14) is provided below the filter screen (13). The sealing block (14) can slide back and forth vertically. The top surface of the sealing block (14) is inclined and has the same inclination direction and inclination angle as the filter screen (13). A drain pipe (15) connected to the outside is installed on the filter box. The bottom of the sealing block (14) is connected to the drive end of the sealing power component (17) via a top rod (16).

3. The marine diesel engine cooling system as described in claim 2, characterized in that, The drain pipe (15) is located at the bottom of the inclined section near the filter screen (13); a seawater filter (18) is installed on the connecting pipe (12).

4. The marine diesel engine cooling system as described in claim 1, characterized in that, The U-shaped water injection rack (311) is horizontally positioned with its opening facing the ice-making mechanism (32); The liquid nitrogen tank (322) is connected to an external liquid nitrogen replenishment device; after ice making, the U-shaped water injection rack (311) is moved horizontally and fully exposes the ice making tube (321); a pushing mechanism (34) is provided above the ice making tube (321), and the pushing mechanism (34) is used to push the ice in the ice making tube (321) out; The two crushing plates (331) can be close to or far from each other, and an ice crushing area for crushing ice is formed between the two crushing plates (331). The conveying auger (332) is used to push the ice chips generated by crushing to the mixing box (5).

5. The marine diesel engine cooling system as described in claim 4, characterized in that, The pushing mechanism (34) includes an electric telescopic rod (341) fixed in the freezer body. The electric telescopic rod (341) is arranged vertically and its actuating end is arranged towards the ice making tube (321). A push plate (342) is installed on the actuating end of the electric telescopic rod (341). The pusher plate (342) is a circular plate and is coaxially arranged with the ice-making tube (321).

6. The marine diesel engine cooling system as described in claim 1, characterized in that, The ice-crushing mechanism (33) includes a conveyor frame (333), the cross-section of which is a U-shaped structure with the opening facing upwards, and the two crushing plates (331) are respectively installed on the two side walls of the conveyor frame (333); A crushing hydraulic cylinder (334) corresponding to the crushing plate (331) is installed on the side wall of the conveyor frame (333). The actuating end of the crushing hydraulic cylinder (334) is connected to the U-shaped push rod (335). Both ends of the U-shaped push rod (335) are connected to the crushing plate (331). The bottom of the conveyor frame (333) is equipped with the transfer auger (332). A screen (336) is provided between the transfer auger (332) and the two crushing plates (331). The screen (336) is horizontally installed between the two side walls of the conveyor frame (333). One end of the transfer auger (332) extends out of the conveyor frame (333) and is powered by the transfer motor (337). The transfer auger (332) pushes the ice chips generated by crushing to the mixing box (5).

7. The marine diesel engine cooling system as described in claim 6, characterized in that, The top of the crushing plate (331) is provided with an outwardly inclined guide part (3311), and the inner wall of the crushing plate (331) is provided with a plurality of anti-slip protrusions (3312). An inclined chute (338) connects the conveyor frame (333) and the mixing box (5). The chute (338) is a closed chute. The top of the chute (338) is located near the other end of the transfer auger (332). The transfer auger (332) pushes the ice chips generated by the crushing into the chute (338). The ice chips entering the chute (338) are slid into the mixing box (5).

8. The marine diesel engine cooling system as described in claim 1, characterized in that, The precooling box (4) includes a precooling box body, which is connected to the freezing box (3). The gas temperature inside the freezing box (3) is lower than the gas temperature inside the precooling box body. The precooling chamber is fixedly provided with a partition (41), which divides the inner cavity of the precooling chamber into an independent blower chamber and a precooling chamber; a fan (42) is installed in the blower chamber, and the fan (42) is connected to the freezer (3) through an air-cooling pipe (43); The precooling chamber is equipped with two air guide pipes (44) and one cooling pipe (45). The two air guide pipes (44) are set perpendicular to the partition (41). One end of the air guide pipe (44) is open and located in the blower chamber. The air guide pipe (44) has several air outlets (441). The air outlets (441) on the two air guide pipes (44) are arranged opposite to each other. The cooling pipe (45) is installed between the two air guide pipes (44). The cooling pipe (45) has an S-shaped structure. The water inlet of the cooling pipe (45) is connected to the water outlet of the filter device (1) through the connecting pipe three (451). The water outlet of the cooling pipe (45) is connected to the mixing box (5).

9. The marine diesel engine cooling system as described in claim 1, characterized in that, The mixing box (5) includes a mixing box body, and a stirring shaft (51) is rotatably installed inside the mixing box body. One end of the stirring shaft (51) is poweredly connected to a stirring motor (52), and a plurality of stirring blades (53) are installed on the stirring shaft (51) along its axial direction. The inner cavity of the mixing chamber is connected to the freezing chamber (3). The inner cavity of the mixing chamber is connected to the precooling chamber (4) through connecting pipe four (54). The ice chips produced by the freezing chamber (3) are mixed with the seawater cooled by the precooling chamber (4) in the mixing chamber. The inner cavity of the mixing chamber is connected to the diesel engine cooling chamber (6) through connecting pipe five (55). The diesel engine cooling chamber (6) is connected to the filter device (1) through connecting pipe six (61).

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