Centrifugal compressor with high bearing heat dissipation capacity

Abstract

The application discloses a centrifugal compressor with high bearing heat dissipation capacity, and relates to the technical field of bearings.The centrifugal compressor comprises a compressor shell, a main shaft, an impeller and a compressor bearing, a recess is formed in the outer wall of the compressor bearing, a bent copper pipe is embedded in the recess, the bent copper pipe is divided into a hot section area and a cold section area, and a heat dissipation auxiliary part is arranged between the compressor shell and the compressor bearing.Through the arrangement of the heat dissipation auxiliary part between the compressor shell and the bearing, unified transportation and end shunting design of the air inlet manifold are realized, the air outlet ends of branch pipes one and two are respectively aligned with the hot section and the cold section area of the bent copper pipe, the targeted cooling and heat dissipation effect of the copper pipe in different heat exchange areas is realized, the air inlet manifold realizes centralized distribution of cooling air, and leakage and flow resistance problems caused by multi-pipeline butt joint are avoided.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, and more specifically to a centrifugal compressor with high-efficiency bearing heat dissipation capability. Background Technology

[0002] In many industrial production fields such as petrochemicals, metallurgy, power generation, and aerospace, high-pressure gas is the core medium for realizing process reactions, fluid transportation, and power drive. Its stable supply is directly related to the continuity and efficiency of the production process. As a key core equipment for preparing high-pressure gas, gas compressors occupy an indispensable position in the industrial production system. Among them, centrifugal gas compressors have significant advantages such as a wide range of gas pressure adjustment, large gas flow rate, low impurity content in compressed gas, and stable quality. They can adapt to the high-pressure gas requirements of different industrial scenarios and have become the mainstream and important tool for obtaining high-pressure gas in various industries. They are widely used in the process systems and power supply systems of large industrial plants.

[0003] The core working component of a centrifugal compressor is a high-speed rotating rotor. As a rotating component, the rotor's stable support relies on specialized bearings. In industrial applications, sliding bearings are commonly used to accommodate the compressor's high-speed, high-load operating characteristics. During compressor operation, the high-speed rotation of the rotor generates friction with the bearings. As operating time increases, the heat generated by this friction accumulates, and the bearing temperature gradually rises. If the heat is not effectively dissipated in time, when the bearing temperature exceeds the tolerance threshold, it will directly cause the bearing pad surface to burn and break, leading to serious failures such as bearing failure and damage to the overall structure. Currently, the mainstream cooling method for this type of bearing in industry is through lubrication. The circulating flow of oil carries away excess heat from the bearing. However, the core function of lubricating oil is to lubricate the mating parts between the bearing and the rotor. Its heat exchange capacity is only an auxiliary function. When the compressor experiences a sudden increase in load, a decrease in motor efficiency leading to an increase in shaft power, or severe fluctuations in operating conditions, the heat exchange efficiency of the lubricating oil may not be able to match the heat generation rate of the bearing. It may not be able to cool down the bearing in time. Excessive bearing temperature will not only lead to a significant increase in the mechanical friction loss of the compressor, reducing the overall operating efficiency of the equipment and increasing energy consumption costs, but will also accelerate the aging and wear of bearing components. In severe cases, it may even directly lead to the complete failure of the bearing, causing the compressor to shut down and resulting in the interruption of industrial production and economic losses.

[0004] While existing technologies have attempted to use bent copper tubes in conjunction with cooling air to assist in heat dissipation of bearings, utilizing the gas-liquid phase change of the phase change working fluid inside the copper tube to achieve heat transfer, this type of heat dissipation method still suffers from insufficient heat dissipation targeting. It does not differentiate the cooling design for the hot and cold sections of the bent copper tube, and a single cooling air path cannot simultaneously meet the heat dissipation needs of different heat exchange areas of the copper tube. The hot section lacks a high-efficiency heat exchange design with forced convection, and the heat release efficiency of the cold section is not fully improved. It is difficult to fully utilize the heat exchange advantages of the heat pipe and cannot meet the bearing heat dissipation requirements under high compressor loads and special operating conditions.

[0005] Meanwhile, the existing cooling airflow cross-sectional area of ​​the heat dissipation system is fixed, and there is no temperature control structure that can dynamically adjust according to the actual operating temperature of the compressor. Continuous heat dissipation in low-temperature environments can easily lead to excessively low bearing temperatures, causing problems such as a sharp increase in lubricating oil viscosity and increased starting friction resistance. This makes the heat dissipation system poorly adaptable to all operating conditions and difficult to control bearing temperature under low temperature and different load scenarios. In addition, there is no flow field optimization structure in the cooling air path, resulting in short contact time between the cooling air and the copper tube heat exchange surface and low heat exchange efficiency. Furthermore, there is no uniform flow guiding structure for the exhaust of cooling air, and the turbulent airflow is prone to generating large flow resistance, resulting in low cooling air utilization efficiency and increased energy consumption, which further restricts the overall heat exchange effect of the bearing heat dissipation system.

[0006] Therefore, in view of this, the present invention proposes a centrifugal compressor with efficient bearing heat dissipation capability to make up for and improve the deficiencies of the prior art. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a centrifugal compressor with efficient bearing heat dissipation capability, thereby resolving the technical issues raised in the background section.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a centrifugal compressor with high-efficiency bearing heat dissipation capability, comprising a compressor housing, a main shaft, an impeller, and a compressor bearing. The outer wall of the compressor bearing has a groove, and a bent copper tube is embedded in the groove. The bent copper tube is divided into a hot section and a cold section. A heat dissipation auxiliary component is provided between the compressor housing and the compressor bearing. The heat dissipation auxiliary component includes an intake manifold connected to the compressor exhaust pipe. The end of the intake manifold is split into branch pipe one and branch pipe two for targeted cooling of different areas of the bent copper tube. The heat dissipation auxiliary component also includes an adjusting baffle, which can change position according to the actual operating temperature of the compressor housing to adjust the flow cross-sectional area of ​​the cooling air in branch pipe one and branch pipe two.

[0009] Furthermore, the bent copper tube is annularly sleeved on the outer wall of the compressor bearing, and the inner wall of the bent copper tube is tightly fitted with the inner wall of the groove. The interior of the bent copper tube is a near-vacuum environment and filled with a phase change liquid working fluid. The portion of the bent copper tube embedded in the groove is a hot section area for absorbing heat from the compressor bearing, and the portion extending outward from the outside of the compressor bearing is a cold section area for releasing heat.

[0010] Furthermore, the outlet end of branch pipe one is aligned with the hot section area of ​​the bent copper pipe, the outlet end of branch pipe two is aligned with the cold section area of ​​the bent copper pipe, and the bottoms of branch pipe one and branch pipe two are connected to each other near the bent copper pipe.

[0011] Furthermore, the length of branch pipe one is greater than the length of branch pipe two, and a hollow chamber is provided inside the compressor housing corresponding to the position of the compressor bearing. The section of branch pipe one that is longer than branch pipe two is located inside the hollow chamber, and a fixed ring is fixedly connected to the outer wall of the extended section.

[0012] Furthermore, the fixed ring divides the hollow chamber into a stepped structure along the axial direction, wherein the inner diameter of the chamber near the hot section of the bent copper tube is smaller than the inner diameter of the chamber near the cold section of the bent copper tube. The fixed ring, as one side edge of the stepped interface, is chamfered to guide the cooling gas to transition smoothly and reduce flow resistance.

[0013] Furthermore, the inner wall of the first branch pipe is fixedly connected with several protruding corner blocks. These protruding corner blocks are used to guide the cooling air to form turbulence, thereby enhancing the convective heat transfer to the hot section of the bent copper pipe. The protruding corner blocks are in the shape of isosceles triangles, with their tips all pointing towards the central axis of the first branch pipe.

[0014] Furthermore, a spiral track is fixedly connected to the inner wall of the second branch pipe, and the spiral track is used to extend the residence time of the cooling gas in the second branch pipe.

[0015] Furthermore, the heat dissipation auxiliary component also includes an exhaust manifold, which is disposed on the compressor housing and connected to the hollow chamber, for discharging the cooling air flowing through branch pipe one and branch pipe two in a unified manner.

[0016] Furthermore, the adjusting stop includes a receiving shaft located between the compressor housing and the hot section region of the bent copper tube, and the receiving shaft is made of a temperature-sensitive elastic material.

[0017] Furthermore, an arc-shaped baffle is fixedly connected to the end of the receiving shaft away from the compressor housing. The arc surface size of the arc-shaped baffle is adapted to the arc surface size of the fixed ring. In the initial state, the arc-shaped baffle is attached to the inner wall of the fixed ring to seal and block the airflow channel of the branch pipe.

[0018] Compared with the prior art, the beneficial effects of the present invention are: (1) This device sets up heat dissipation auxiliary components between the compressor housing and the bearing, and relies on the unified delivery and end-of-pipe diversion design of the main intake pipe to allow the outlet ends of branch pipe one and branch pipe two to be specifically aligned with the hot and cold sections of the bent copper pipe, respectively, thereby achieving targeted cooling and heat dissipation effects for different heat exchange areas of the copper pipe. The main intake pipe realizes centralized allocation of cooling gas, avoiding leakage and flow resistance problems caused by multi-pipe connection. Branch pipe one provides differentiated cooling for the forced heat exchange needs of the hot section area and branch pipe two provides differentiated cooling for the heat release needs of the cold section area. At the same time, the interconnection at the bottom of the two realizes the flow field interconnection, avoiding uneven heat exchange caused by pressure imbalance of a single gas path. This changes the status quo of unstable and inefficient heat exchange of the traditional single gas path, allowing the cooling gas to play a role according to the heat exchange characteristics of different areas of the copper pipe, greatly improving the heat exchange stability and overall utilization efficiency of the cooling gas path.

[0019] This device achieves low flow resistance and high stability in the cooling air path through targeted optimization of the structure of each heat dissipation auxiliary component. Combined with the coordinated operation of the hollow chamber, fixed ring, and exhaust manifold, it further enhances the efficiency and continuity of bearing heat dissipation. The isosceles triangular convex block on the inner wall of branch pipe one guides the cooling air to form turbulence, enhancing convective heat transfer in the hot section. The spiral track on the inner wall of branch pipe two extends the residence time of the cooling air, improving the heat transfer effect in the cold section. The fixed ring divides the hollow chamber into a stepped structure and is chamfered, which guides the cooling air to transition smoothly and reduces flow resistance. The exhaust manifold enables the unified discharge of cooling air, avoiding the accumulation of hot air and secondary heating. The optimized design of each structure allows the cooling air to operate efficiently throughout the entire process from delivery and heat exchange to discharge. At the same time, the hollow chamber provides a stable installation and protection space for the branch pipes, improving the overall stability of the heat dissipation structure and allowing the bearing heat dissipation system to function reliably for a long time.

[0020] (2) This device sets an adjustment baffle between the compressor housing and the hot section of the bent copper tube. Relying on the temperature-sensitive elastic material of the receiving shaft, it realizes the power-free adaptive on / off adjustment of the cooling air path. It improves the problem of overcooling of the compressor bearing in low-temperature winter conditions. The receiving shaft can complete the autonomous deformation of thermal expansion and room temperature reset according to the actual working temperature of the bearing. It does not require external electrical control equipment and drive components. It directly converts the temperature signal into mechanical power to drive the arc baffle to complete the sealing and opening of the branch pipe airflow channel. When the bearing temperature is in the overcooled range, it cuts off the forced cooling air path of the hot section to avoid the continuous direct blowing of cooling air, which would cause the bearing temperature to drop further. It allows the bearing to heat up naturally by friction, effectively preventing the problem of increased viscosity and poor fluidity of lubricating oil due to low temperature. It avoids the risk of cold start dry grinding and bearing wear from the root.

[0021] By adapting the arc surface dimensions of the arc-shaped baffle to those of the fixed ring, and combining this with the design of the arc-shaped baffle gradually moving due to the gradual deformation of the receiving shaft, stable control of bearing temperature and stable maintenance of the lubricating oil film are achieved. The matching design of the arc-shaped baffle and the fixed ring ensures the sealing effect of the airflow channel of the branch pipe at low temperatures, preventing cooling gas leakage and ineffective heat exchange. The receiving shaft does not deform instantaneously, but gradually extends and contracts with the bearing temperature change, allowing the arc-shaped baffle to slowly adjust the cross-sectional area of ​​the cooling gas flow in the branch pipe. This avoids sudden influx or cutoff of cooling gas, which could cause a sudden rise or fall in bearing temperature, ensuring a stable transition in bearing temperature. This allows the lubricating oil film to gradually form and remain stable, avoiding unit vibration and rotor instability caused by an excessively thick oil film.

[0022] Most importantly, by coordinating the adjustment baffle with the phase change heat exchange structure of the bent copper tube in Embodiment 1 and the targeted cooling air path, temperature control of the compressor bearing under all operating conditions is achieved, significantly improving the environmental adaptability and operational reliability of the equipment. The adjustment baffle can flexibly adjust the heat exchange intensity of the cooling air path according to the bearing temperature change. When the bearing is in the optimal operating range, branch pipe 1 is fully opened, allowing the cooling air path of Embodiment 1 to operate at full load. Relying on the efficient phase change heat exchange of the bent copper tube and the targeted heat exchange of the cooling air, excess heat generated by the bearing under high load is quickly removed, preventing the bearing bush from burning out. When the bearing temperature drops, the air path is gradually blocked, allowing the heat exchange rate to match the heat generation rate in real time. The entire structure achieves closed-loop control of the bearing temperature, ensuring that the bearing can stably remain in the optimal temperature range under different operating conditions such as low temperature in winter, normal operation, and high load operation. This reduces the abnormal bearing clearance caused by the thermal expansion and contraction of metal, extending the service life of the bearing and the entire machine. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the axial view of the three-dimensional structure of the present invention; Figure 2 This is a side view schematic diagram of the structure of the present invention; Figure 3 This is a three-dimensional structural diagram of the compressor bearing of the present invention; Figure 4 This is a three-dimensional structural diagram illustrating the positional relationship between the compressor bearing and the bent copper tube of the present invention; Figure 5 This is a three-dimensional schematic diagram of the heat dissipation auxiliary component in Embodiment 1 of the present invention; Figure 6 This is a schematic plan view of the relevant structure of the heat dissipation auxiliary component in Embodiment 1 of the present invention; Figure 7 This is a top view of the convex corner block and the spiral track in Embodiment 1 of the present invention; Figure 8This is a three-dimensional structural diagram of the adjusting stop in Embodiment 2 of the present invention; Figure 9 This is a schematic diagram of the arc-shaped baffle in Embodiment 2 of the present invention; Figure 10 This is a three-dimensional schematic diagram of the arc-shaped baffle in Embodiment 2 of the present invention.

[0024] The following components are labeled in the diagram: 1. Compressor housing; 11. Compressor exhaust pipe; 12. Main shaft; 13. Impeller; 14. Compressor bearing; 1401. Groove; 15. Bending copper pipe; 2. Heat dissipation auxiliary component; 21. Inlet main pipe; 22. Branch pipe one; 2201. Protruding corner block; 23. Branch pipe two; 2301. Spiral track; 24. Hollow chamber; 25. Fixing ring; 26. Exhaust main pipe; 27. Adjusting stop; 2701. Receiving shaft; 2702. Arc-shaped baffle. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1: Please refer to Figure 1 - Figure 5 As shown, a centrifugal compressor with high-efficiency bearing heat dissipation capability includes a compressor housing 1, a main shaft 12, an impeller 13, and a compressor bearing 14. The outer wall of the compressor bearing 14 has a groove 1401, and a bent copper tube 15 is embedded in the groove 1401. The bent copper tube 15 is divided into a hot section area and a cold section area. A heat dissipation auxiliary component 2 is provided between the compressor housing 1 and the compressor bearing 14. The heat dissipation auxiliary component 2 includes an intake main pipe 21 connected to the compressor exhaust pipe 11. The end of the intake main pipe 21 is split into a branch pipe 1 22 and a branch pipe 23, which are used to provide targeted cooling and heat dissipation for different areas of the bent copper tube 15.

[0027] It should be noted that the bent copper tube 15 is annularly sleeved on the outer wall of the compressor bearing 14, and the inner wall of the bent copper tube 15 is tightly fitted with the inner wall of the groove 1401. The interior of the bent copper tube 15 is a near-vacuum environment and is filled with a phase change liquid working fluid. The part of the bent copper tube 15 embedded in the groove 1401 is the hot section area for absorbing heat from the compressor bearing 14, and the part extending out of the compressor bearing 14 is the cold section area for releasing heat.

[0028] It is worth noting that the compressor bearing 14 is a sliding bearing and a core component supporting the high-speed rotation of the compressor rotor. In existing technology, it relies on lubricating oil for lubrication and basic heat dissipation during operation. However, lubricating oil has a suitable operating temperature range: when the lubricating oil temperature is too low, the oil viscosity will increase sharply, making it impossible to form a stable lubricating film on the bearing friction surface, resulting in a significant decrease in lubrication effect; when the lubricating oil temperature is too high, the oil is prone to deterioration and its heat exchange capacity is insufficient, failing to remove frictional heat in time, which can easily cause the bearing pads of the compressor bearing 14 to burn and be damaged. Therefore, in the lubrication process... Before the lubricating oil enters the compressor bearing 14, the temperature of the lubricating oil needs to be precisely adjusted by the oil cooler. Taking No. 46 lubricating oil as an example, after it is adjusted to the preset temperature of 43°C by the oil cooler, it is introduced into the lubrication channel of the compressor bearing 14 to provide lubrication for the bearing and remove some of the frictional heat. However, the inlet temperature of the lubricating oil is a fixed value. When the compressor load increases, the frictional heat generation rate of the compressor bearing 14 increases sharply. The lubricating oil inside the bearing will be rapidly heated to a temperature exceeding the preset temperature. The basic heat dissipation of the lubricating oil alone cannot meet the cooling requirements, and there is still a risk of bearing burnout.

[0029] To address the shortcomings of relying solely on lubricating oil for heat dissipation, an annular groove 1401 is formed on the outer wall of the compressor bearing 14. A bent copper tube 15 is tightly embedded within the groove 1401. The bent copper tube 15 has a near-vacuum internal structure and is filled with a phase-change liquid working fluid. The bent copper tube 15 achieves efficient heat dissipation of the compressor bearing 14 based on the phase-change heat transfer principle. Specifically, the heat generated by the compressor bearing 14 during operation is transferred to the hot section of the bent copper tube 15. Because the interior of the bent copper tube 15 is a near-vacuum environment... The phase change liquid working fluid inside the tube vaporizes after absorbing a small amount of heat. The vaporized working fluid moves towards the cold section region of the bent copper tube 15 with the flow field inside the tube. The cold section region is kept at a low temperature after being ventilated and heated by cooling gas. The vaporized working fluid liquefies when it encounters cold in the cold section region. During the liquefaction process, a large amount of latent heat is released. The latent heat is quickly carried away by the cooling gas, completing one heat exchange cycle. The liquefied liquid working fluid flows back to the hot section region under the action of gravity and capillary force inside the tube, continuously absorbing the heat of the compressor bearing 14, and achieving continuous and efficient heat dissipation of the bearing.

[0030] Please refer to Figure 5 - Figure 7As shown, the outlet end of branch pipe 1 22 is aligned with the hot section area of ​​the bent copper pipe 15, and the outlet end of branch pipe 23 is aligned with the cold section area of ​​the bent copper pipe 15. The bottoms of branch pipe 1 22 and branch pipe 23 are connected to each other near the bent copper pipe 15. The length of branch pipe 1 22 is greater than the length of branch pipe 23. A hollow chamber 24 is provided inside the compressor housing 1 at the position corresponding to the compressor bearing 14. The section of branch pipe 1 22 that is longer than branch pipe 23 is located inside the hollow chamber 24. A fixing ring 25 is fixedly connected to the outer wall of the extended section. The fixing ring 25 divides the hollow chamber 24 into a stepped structure along the axial direction. The inner diameter of the chamber near the hot section area of ​​the bent copper pipe 15 is smaller than the inner diameter of the chamber near the cold section area of ​​the bent copper pipe 15. The edge of the fixing ring 25 as the stepped interface is chamfered to guide the cooling air to transition smoothly and reduce flow resistance.

[0031] It should be noted that the inner wall of branch pipe 1 22 is fixedly connected with several protruding corner blocks 2201. These protruding corner blocks 2201 are used to guide the cooling air to form turbulence and enhance the convective heat transfer of the hot section of the bent copper pipe 15. The protruding corner blocks 2201 are in the shape of isosceles triangles, and their tips are all facing the central axis of branch pipe 1 22. The inner wall of branch pipe 23 is fixedly connected with a spiral track 2301. The spiral track 2301 is used to extend the residence time of the cooling air in branch pipe 23. The heat dissipation auxiliary component 2 also includes an exhaust manifold 26. The exhaust manifold 26 is set on the compressor housing 1 and connected to the hollow chamber 24. It is used to discharge the cooling air flowing through branch pipe 1 22 and branch pipe 23 in a unified manner.

[0032] Specifically, in this embodiment, the centrifugal compressor bearing heat dissipation is based on the phase change heat transfer of the bent copper tube 15, combined with the targeted cooling air path formed by the intake main pipe 21, branch pipe one 22, branch pipe two 23, hollow chamber 24, fixed ring 25, and exhaust main pipe 26 of the heat dissipation auxiliary component 2. This complements the basic lubrication and heat dissipation of the lubricating oil, achieving efficient and targeted heat dissipation of the compressor bearing 14. Its working principle and process are described in stages as follows: Phase 1: Basic Lubrication and Heat Dissipation with Lubricating Oil. After the compressor starts, the main shaft 12 drives the impeller 13 to rotate at high speed. The compressor bearing 14, as a sliding support component, generates friction and heat continuously between itself and the rotor. Lubricating oil, pre-adjusted to a preset temperature (e.g., 46# lubricating oil adjusted to 43°C via an oil cooler), is introduced into the lubrication channel of the compressor bearing 14. This forms a stable lubricating film on the bearing friction surface, reducing mechanical friction loss, and also carries away some of the heat generated by the bearing through heat conduction, completing the basic lubrication and heat dissipation process. During this process, the lubricating oil, due to its fixed inlet temperature, can only be adapted to the compressor... At low loads, the heat generation rate of the compressor results in excess heat being continuously transferred to the outer wall of the compressor bearing 14. Since the bent copper tube 15 is tightly embedded in the groove 1401 on the outer wall of the bearing in a ring shape, and the inside of the copper tube is a near-vacuum environment filled with a phase change liquid working fluid, the heat from the outer wall of the bearing is quickly transferred to the hot section of the bent copper tube 15. After absorbing heat, the phase change liquid working fluid inside the tube begins to undergo a vaporization reaction. Through the physical characteristics of gas-liquid phase change, the bent copper tube 15 achieves rapid absorption and temporary heat storage of the bearing heat, preparing for the heat exchange of the subsequent cooling gas path. Its near-vacuum internal structure significantly reduces the heat threshold of the working fluid vaporization and improves the heat absorption efficiency.

[0033] The second stage: Cooling gas diversion and delivery, specifically targeting the hot and cold sections of the bent copper tube 15. As heat continues to accumulate in the compressor bearing 14, a large amount of working fluid in the hot section of the bent copper tube 15 vaporizes and moves towards the cold section. Simultaneously, the cooling gas path of the heat dissipation auxiliary component 2 is activated. The high-pressure gas in the compressor exhaust pipe 11, after being cooled by the cooler, enters the intake manifold 21 connected to the exhaust pipe. The intake manifold 21 serves as a unified delivery channel for cooling gas, achieving centralized distribution of cooling gas and avoiding leakage and flow resistance problems caused by multiple pipe connections. After the cooling gas is stabilized in the intake manifold 21, it is diverted at the end into branch pipe one 22 and branch pipe two 23. The outlet of branch pipe one 22 faces the hot section of the bent copper tube 15, and the outlet of branch pipe two 23 faces the cold section of the bent copper tube 15. This achieves differentiated and targeted delivery of cooling gas to different heat exchange areas of the copper tube, improving the problems of inaccurate and inefficient heat exchange in traditional single-path systems. During this process, if... Figure 5 and Figure 6 As shown, branch pipe 22 needs to extend into the hot section area of ​​the bearing, so its length is designed to be greater than that of branch pipe 23. The extended section is embedded in the hollow chamber 24 opened at the bearing position of the compressor housing 1. The hollow chamber 24 provides a stable installation and protection space for branch pipe 22, avoiding loosening and damage of the branch pipe caused by compressor operation vibration, and improving the stability of the gas circuit structure.

[0034] Phase Three: As Figure 6 and Figure 7As shown, the hot section undergoes forced turbulent heat transfer, while the cold section features extended contact heat transfer, achieving efficient heat release from the copper tube. After the cooling gas enters branch pipe 1 (22), it collides with several isosceles triangular convex blocks 2201 fixedly connected to the inner wall of the pipe during its forward flow. Since the tips of the convex blocks 2201 all face the central axis of branch pipe 1 (22), the original laminar flow state of the cooling gas is broken by the obstruction and guidance of the convex blocks 2201, forming a violent turbulent flow field. This turbulent flow field significantly increases the contact area between the cooling gas and the hot section of the bent copper tube 15, achieving forced convection heat transfer in the hot section area. This not only quickly removes the surface heat of the hot section of the bent copper tube 15 but also accelerates the vaporization rate of the working fluid inside the tube, enhancing the heat absorption capacity of the copper tube. Simultaneously, after the cooling gas enters branch pipe 2 (23), it flows forward in a spiral shape along the fixed spiral track 2301 on the inner wall of the pipe. 2301 significantly extends the flow path and residence time of the cooling gas in branch pipe 23, allowing the cooling gas to fully exchange heat with the cold section of the bent copper pipe 15. At this time, the gaseous substance in the cold section of the bent copper pipe 15 undergoes a rapid liquefaction reaction and releases a large amount of latent heat under the continuous low temperature of the cooling gas. The latent heat is absorbed by the cooling gas in time, completing the efficient release of heat from the bent copper pipe 15. The liquefied liquid working fluid flows back to the hot section under the combined action of gravity and capillary force in the pipe to absorb heat from the compressor bearing 14 again, forming a phase change heat cycle inside the bent copper pipe 15. During this process, the bottoms of branch pipe 12 and branch pipe 23 are connected to each other near the bent copper pipe 15, realizing the interconnection of the flow fields of the two cooling gas paths. This avoids heat exchange imbalance caused by excessively high or low pressure in a single gas path, ensuring the synchronicity and stability of heat exchange between the hot and cold sections.

[0035] The fourth stage: The cooling air is guided in a stepped manner, and then uniformly collected and discharged to complete the overall heat dissipation cycle. After heat exchange between branch pipe 1 22 and branch pipe 2 23, the cooling air is located inside the hollow chamber 24. Since the outer wall of the extended section of branch pipe 1 22 is fixedly connected to a fixed ring 25, and the fixed ring 25 divides the hollow chamber 24 into a stepped structure along the axial direction, the inner diameter of the chamber near the hot section of the bent copper pipe 15 is smaller than that of the cold section. Therefore, when the cooling air flows towards the exhaust manifold 26, the flow channel space gradually expands, the flow velocity is reasonably buffered, and the airflow turbulence caused by sudden changes in flow resistance is avoided. At the same time, the fixed ring 25, as one side edge of the stepped interface, is chamfered, which forms a smooth guiding effect on the cooling air, further reducing the flow resistance of the cooling air in the hollow chamber 24, reducing the energy loss of cooling air transportation, and allowing the cooling air to be collected smoothly.

[0036] Finally, the cooling air carrying heat in the hollow chamber 24 all enters the exhaust manifold 26 connected to the hollow chamber 24. The exhaust manifold 26 serves as a unified discharge channel for the cooling air, quickly expelling the heat-exchanged hot airflow outside the compressor housing 1. This prevents the hot airflow from accumulating inside the housing and causing secondary heating, ensuring the continuous and efficient operation of the heat dissipation system. Thus, the entire process of cooling air being diverted from the intake manifold 21 → targeted heat exchange in branch pipe 1 22 and branch pipe 2 23 → stepped flow guidance in the hollow chamber 24 → unified discharge in the exhaust manifold 26 is completed. This process is linked with the phase change heat cycle of the bent copper pipe 15 and the basic heat dissipation of the lubricating oil, achieving efficient heat dissipation of the compressor bearing 14 throughout the entire process and in multiple dimensions. Even under special operating conditions with increased compressor load, it can quickly remove excess heat from the bearing and avoid the risk of bearing burnout.

[0037] It should be added that the structure involved in this embodiment is specifically designed for the special working scenario of the compressor bearing 14, which is small and subject to high vibration. It focuses on solving the technical problem that it is impossible to perform differentiated and asymmetrical cooling on different sections of the annular heat pipe under limited installation space and strong vibration conditions. By using the intake manifold 21 to divert the air and the branch pipe 1 22 and branch pipe 2 23 to supply air to the hot and cold sections respectively, targeted enhanced heat dissipation is achieved for different areas of the bent copper pipe 15.

[0038] Example 2: Based on Example 1, please refer to... Figure 8 - Figure 10 As shown, the adjusting stop 27 includes a receiving shaft 2701, which is located between the compressor housing 1 and the hot section area of ​​the bent copper tube 15. The receiving shaft 2701 is made of a temperature-sensitive elastic material.

[0039] It should be noted that an arc-shaped baffle 2702 is fixedly connected to the end of the receiving shaft 2701 away from the compressor housing 1. The arc surface size of the arc-shaped baffle 2702 is adapted to the arc surface size of the fixed ring 25. In the initial state, the arc-shaped baffle 2702 fits against the inner wall of the fixed ring 25 to seal and block the airflow passage of the branch pipe 22.

[0040] It should be noted that this embodiment focuses on the temperature control of the centrifugal compressor bearing 14. Since the operating temperature of the compressor bearing 14 is not necessarily better the lower it is, there is an optimal operating range. Furthermore, continuous strong cooling in winter can easily lead to lubrication failure and thermal stress damage.

[0041] According to the centrifugal compressor industry specifications and the GB / T755-2019 standard, the temperature of the compressor bearing 14 and the lubricating oil must be controlled within a reasonable range: the optimal operating temperature of the sliding bearing is 45~50℃, the optimal operating temperature of the rolling bearing should not exceed 70℃, and the temperature rise should not exceed 40℃; within this range, the bearing lubricating film can remain stable, the friction loss is at a low level, and the bearing can be guaranteed to operate reliably for a long time.

[0042] However, when the bearing and lubricating oil temperatures are too low, multiple hazards will occur: First, the viscosity of the lubricating oil will increase sharply, resulting in poor fluidity. During cold starts, dry friction is likely to occur. Data shows that when the oil temperature is below 25°C, the viscosity of the lubricating oil can soar to 3-5 times the design value, and the wear during low-temperature starts can be more than 10 times that of high-temperature wear, making bearing wear very easy to occur. Second, an excessively thick oil film will cause unit vibration and damage the rotor's operational stability. Third, the thermal expansion and contraction effect of metals will cause abnormal bearing clearance, further aggravating friction and impact between components. Especially in low-temperature environments in winter, if the cooling air is continuously blown directly onto the compressor bearing 14, its operating temperature is likely to be below 30°C, forming an "overcooled" condition. At this time, the fluidity of the lubricating oil will decrease significantly, and it will be unable to effectively form a uniform lubricating film. Long-term operation will cause the Babbitt alloy of the bearing to fall off, causing thermal stress damage and lubrication failure, seriously affecting the service life of the compressor bearing 14 and the entire machine.

[0043] It should be added that the bearing 2701 uses a temperature-sensitive elastic material that expands under heat and returns to its original position at room temperature. This material is preferably a bimetallic composite material or a shape memory alloy such as a Ti-Ni based shape memory alloy. Both types of materials are suitable for the operating temperature range of the compressor bearing 14 and meet the requirements for elastic deformation and return to its original position. Among them, the bimetallic composite material is made of two layers of metals with significantly different thermal expansion coefficients, such as high manganese steel and Invar steel, rolled together. When the temperature of the compressor bearing 14 rises to the preset threshold of 45°C, the two layers of metal undergo bending deformation due to the difference in thermal expansion, which drives the arc-shaped baffle 2702 to move. When the temperature drops back to the normal / low temperature range, the metal returns to its original shape, and the receiving shaft 2701 drives the arc-shaped baffle 2702 to reset and seal. The material has low cost, is suitable for industrial-grade high / low temperature working conditions, and the deformation response temperature can be accurately controlled by the metal ratio.

[0044] Ti-Ni based shape memory alloy: It has excellent shape memory effect and elasticity. It maintains a preset shrinkage shape at low temperature so that the arc baffle 2702 fits and fixes the ring 25. When the temperature rises to the optimal operating temperature of the compressor bearing 14, which is 45~50℃, the alloy automatically returns to the expansion shape, pushing the arc baffle 2702 to open. It has high deformation accuracy and strong fatigue resistance, and can adapt to the long-term repeated temperature changes of the compressor, resulting in a long service life.

[0045] Specifically, in Embodiment 2, based on the phase change heat transfer of the bent copper tube 15 and the targeted cooling air path in Embodiment 1, an adjustment baffle 27 is added. By utilizing the deformation characteristics of the temperature-sensitive elastic material, the temperature adaptive on / off / opening degree adjustment of the cooling air path is achieved, solving the "overcooling" problem of the compressor bearing 14 in winter / low temperature environments and ensuring that the compressor bearing 14 is always in the optimal operating temperature range.

[0046] In low-temperature winter environments, before compressor startup / under low load operation, the initial temperature of compressor bearing 14 is below 35℃, placing it in the "overcooling" risk zone. At this time, the receiving shaft 2701, due to the low-temperature environment, maintains its original contracted / reset shape. The end away from the compressor housing 1 drives the arc-shaped baffle 2702 to fit tightly against the inner wall of the fixed ring 25. Since the arc size of the arc-shaped baffle 2702 matches the arc size of the fixed ring 25, their fit together achieves complete sealing of the airflow channel of branch pipe 22. The core function of this structural design is to cut off the hot section area of ​​the bent copper pipe 15. The forced cooling air path prevents the cooling air from blowing directly onto the hot section area, which would cause the bearing temperature to drop further. At the same time, the fixed ring 25 provides a stable contact support surface for the arc-shaped baffle 2702, ensuring the sealing performance and preventing the cooling air leakage from causing ineffective heat exchange. In this stage, only a small amount of cooling air flows through the branch pipe 23 to the cold section area of ​​the bent copper pipe 15 in the first embodiment, and there is no forced heat exchange in the hot section. The phase change heat transfer rate of the bent copper pipe 15 slows down, and the compressor bearing 14 gradually heats up by generating heat through rotor friction. The viscosity of the lubricating oil gradually decreases as the temperature rises, and its fluidity is restored, avoiding the problem of dry friction during cold start.

[0047] When the compressor bearing 14 heats up to the lower limit of its optimal operating temperature through frictional heat generation, the heat generated by the compressor bearing 14 is transferred through the hot section area of ​​the bent copper tube 15 to the receiving shaft 2701 between the compressor housing 1 and the hot section. Because the receiving shaft 2701 is made of bimetallic composite material / Ti-Ni based shape memory alloy, it undergoes thermal expansion / shape recovery deformation triggered by temperature rise, generating an outward stretching force in its axial direction. This pushes the arc-shaped baffle 2702 fixed at the end to move along the inner wall of the fixed ring 25 away from the air inlet of the branch pipe 22. During this process, the receiving shaft 2701, as the core component for temperature sensing and power transmission, directly converts the temperature signal into mechanical deformation. The system operates without external drive equipment, enabling power-free adaptive adjustment of the cooling system. The gradual movement of the arc-shaped baffle 2702 ensures that the airflow channel of branch pipe 1 22 opens gradually rather than opening completely at once. This prevents a sudden surge of cooling air that could cause a rapid drop in the temperature of the compressor bearing 14, achieving a smooth transition of ambient temperature and ensuring the gradual formation and stability of the lubricating oil film. As the arc-shaped baffle 2702 moves, the cross-sectional area of ​​the cooling airflow in branch pipe 1 22 gradually increases, and a small amount of cooling air begins to flow in and perform light heat exchange on the hot section of the bent copper pipe 15. Combined with the heat exchange in the cold section of branch pipe 2 23, this keeps the bearing temperature within the initial optimal range of around 45°C.

[0048] When the compressor enters normal / high load operation, the rotor friction heat generation rate increases, and the temperature of the compressor bearing 14 rises to the optimal operating range of 45~50℃, and continues to approach the upper limit of 50℃. At this time, the receiving shaft 2701 is affected by the continuous temperature rise and completes the maximum thermal deformation, causing the arc baffle 2702 to completely break away from the sealed contact with the inner wall of the fixed ring 25. The airflow channel of the branch pipe 22 is fully opened, and the cross-sectional area of ​​the cooling airflow reaches the maximum value. The core function of the adjusting baffle 27 at this stage is to release the cooling air path restriction, ensuring that the cooling air from the compressor exhaust pipe 11 flows through the branch pipe 22 to the hot section area of ​​the bent copper pipe 15 after being stabilized and diverted by the intake main pipe 21. This ensures that the compressor bearing 14 does not overheat under high load and avoids the bearing bush burning out.

[0049] Before the compressor load decreases or the compressor stops, the rotor friction heat generation decreases, and the temperature of the compressor bearing 14 gradually drops from the optimal operating range. When the temperature is below 45°C, the receiving shaft 2701 gradually returns to its original contraction / reset state due to the decrease in ambient temperature, generating an inward contraction force in the axial direction. This causes the arc-shaped baffle 2702 to move along the inner wall of the fixed ring 25 towards the air inlet of the branch pipe 22. The cooling airflow cross-sectional area of ​​the branch pipe 22 gradually decreases as the baffle moves. When the compressor stops completely and the temperature of the compressor bearing 14 drops back to the normal temperature / winter low temperature range, the receiving shaft 2701 completes its full reset. The arc-shaped baffle 2702 then tightly adheres to the inner wall of the fixed ring 25 again, sealing the branch pipe 22 and preparing for the next low-temperature start-up, thus preventing the cooling air from continuously and strongly cooling the bearing.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A centrifugal compressor with high-efficiency bearing heat dissipation capability, comprising a compressor housing (1), a main shaft (12), an impeller (13), and a compressor bearing (14), wherein a groove (1401) is formed on the outer wall of the compressor bearing (14), and a bent copper tube (15) is embedded in the groove (1401), characterized in that: The bent copper tube (15) is divided into a hot section area and a cold section area, and a heat dissipation auxiliary component (2) is provided between the compressor housing (1) and the compressor bearing (14). The heat dissipation auxiliary component (2) includes an intake manifold (21) connected to the compressor exhaust pipe (11). The end of the intake manifold (21) is divided into a branch pipe one (22) and a branch pipe two (23) for targeted cooling and heat dissipation of different areas of the bent copper pipe (15). The heat dissipation auxiliary component (2) also includes an adjustment baffle (27), which can change position according to the actual operating temperature of the compressor housing (1) to adjust the flow cross-sectional area of ​​the cooling gas in the first branch pipe (22) and the second branch pipe (23); The length of the first branch pipe (22) is greater than the length of the second branch pipe (23). A hollow chamber (24) is provided inside the compressor housing (1) at the position corresponding to the compressor bearing (14). The section of the first branch pipe (22) that is longer than the second branch pipe (23) is located inside the hollow chamber (24). A fixed ring (25) is fixedly connected to the outer wall of the extended section. The adjusting stop (27) includes a receiving shaft (2701) located between the compressor housing (1) and the hot section area of ​​the bent copper tube (15), and the receiving shaft (2701) is made of a temperature-sensitive elastic material; An arc-shaped baffle (2702) is fixedly connected to one end of the receiving shaft (2701) away from the compressor housing (1). The arc surface size of the arc-shaped baffle (2702) is adapted to the arc surface size of the fixed ring (25). In the initial state, the arc-shaped baffle (2702) fits against the inner wall of the fixed ring (25) to seal and block the airflow channel of the branch pipe (22).

2. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The bent copper tube (15) is annularly sleeved on the outer wall of the compressor bearing (14), and the inner wall of the bent copper tube (15) is tightly fitted with the inner wall of the groove (1401). The interior of the bent copper tube (15) is a near-vacuum environment and is filled with a phase change liquid working fluid. The part of the bent copper tube (15) embedded in the groove (1401) is the hot section area for absorbing heat from the compressor bearing (14), and the part extending out of the compressor bearing (14) is the cold section area for releasing heat.

3. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The outlet of the first branch pipe (22) is aligned with the hot section of the bent copper pipe (15), and the outlet of the second branch pipe (23) is aligned with the cold section of the bent copper pipe (15). The bottoms of the first branch pipe (22) and the second branch pipe (23) are connected to each other near the bent copper pipe (15).

4. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The fixed ring (25) divides the hollow chamber (24) into a stepped structure along the axial direction. The inner diameter of the chamber near the hot section of the bent copper tube (15) is smaller than the inner diameter of the chamber near the cold section of the bent copper tube (15). The fixed ring (25) is chamfered on one side of the stepped interface to guide the cooling gas to transition smoothly and reduce flow resistance.

5. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The inner wall of the branch pipe (22) is fixedly connected with several protruding corner blocks (2201). The protruding corner blocks (2201) are used to guide the cooling gas to form turbulence and enhance the convective heat transfer of the hot section of the bent copper pipe (15). The protruding corner blocks (2201) are in the shape of isosceles triangles, and their tips are all facing the central axis of the branch pipe (22).

6. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The inner wall of the second branch pipe (23) is fixedly connected with a spiral track (2301), which is used to extend the residence time of the cooling gas in the second branch pipe (23).

7. A centrifugal compressor with high-efficiency bearing heat dissipation capability according to claim 1, characterized in that: The heat dissipation auxiliary component (2) also includes an exhaust manifold (26), which is disposed on the compressor housing (1) and connected to the hollow chamber (24) to discharge the cooling gas flowing through the branch pipe one (22) and the branch pipe two (23) in a unified manner.

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