Propeller erosion experiment device and erosion experiment method

Abstract

The invention relates to a propeller erosion experiment device and an erosion experiment method, which are used for testing erosion corrosion characteristics of a propeller under a simulated polar region condition. The experimental device comprises a box body, a driving mechanism and a thrust measuring assembly, the box body is provided with a feeding port for feeding an experimental medium; the driving mechanism is connected with the propeller and drives the propeller to rotate; the thrust measuring assembly comprises a shaft body, a stress plate and a thrust sensor, the shaft body horizontally penetrates through the box body and can move in the horizontal direction, the stress plate is connected with one end of the shaft body and right faces the propeller, the thrust sensor is connected with the other end of the shaft body, and the thrust load generated by the propeller is transmitted to the thrust sensor through the stress plate and the shaft body. Compared with the prior art, the impact, cutting and blocking effects of the propeller and sea ice in the propelling process can be reproduced in the horizontal direction, and the goodness of fit between the test result and the actual icebreaking operation stress condition is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of testing equipment technology, and in particular to a propeller erosion test apparatus and erosion test method. Background Technology

[0002] Erosion is a phenomenon caused by the interaction between fluids and solids or between solids, resulting in damage to the surface of materials. As a core component of a ship's propulsion system, the propeller is fundamental to ensuring the operational capability and safety of heavy icebreakers. In polar waters, propellers experience blockages, cutting, and collisions with sea ice, subjected to loads hundreds of times greater than in open water. Therefore, studying the erosion corrosion characteristics of ship propellers under polar conditions is of great significance.

[0003] Current propeller experimental devices still have many shortcomings. For example, CN108267307A discloses an experimental device for simulating the erosion and wear of marine propellers, including a frame, a slurry tank, a propeller drive mechanism, and a spring force gauge. By preparing slurry containing sand in the slurry tank and using a variable frequency speed-regulating motor to drive the propeller to rotate, the thrust and wear generated by the propeller rotation are measured to analyze the propeller's resistance to mud and sand erosion. However, this device has a vertically positioned propeller, gravity interferes with the thrust measurement, and it can only rotate in place, making it unable to reproduce the dynamic erosion process during horizontal propulsion; moreover, it lacks low-temperature-ice-sand coupling conditions and multi-parameter synchronous measurement.

[0004] CN109870296A discloses a propeller performance testing system for ice-paddle flow in a circulating water tank. The system includes a model ice driving device, a model ice fixing device, a propeller overall thrust and torque measuring device, a propeller single-blade five-component measuring device, a high-speed camera, a light source, and a debris filter. These devices simulate the ice-paddle flow environment to measure the propeller's overall thrust, torque, and single-blade load. However, this system simulates ice-paddle action by moving a fixed ice model as a whole, which limits the ice block trajectory and cannot reproduce the intake-jamming-secondary cutting process. It also requires a large circulating water tank, resulting in high energy consumption and a single method for ice particle replenishment.

[0005] Furthermore, in simulating the ice load erosion environment in polar seas, most existing propeller experimental devices are vertical structures. When simulating the interaction between the propeller and the ice-water mixture, this structure cannot accurately reflect the stress situation of the propeller in actual icebreaking operations, and cannot accurately simulate the collision and cutting process of the propeller with sea ice during horizontal propulsion, resulting in a large deviation between the experimental results and the actual working conditions.

[0006] Therefore, there is an urgent need to develop a new type of propeller erosion test device that can simulate the collision and cutting process of propellers with sea ice during horizontal propulsion, and provide high-precision experimental support for the evaluation of the anti-icing performance of ship propellers and the research on material modification. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of existing technologies that cannot accurately simulate the collision and cutting process of a propeller with sea ice during horizontal propulsion, and to provide a propeller erosion experimental device and erosion experimental method.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] The present invention first provides a propeller erosion test device for testing the erosion and corrosion characteristics of a propeller under simulated polar conditions. The test device includes a housing, a drive mechanism and a thrust measurement component, with the propeller to be tested horizontally placed inside the housing.

[0010] The box is equipped with a dispensing port for dispensing experimental media into the box.

[0011] The drive mechanism is located outside the housing, and it is connected to the propeller and used to drive the propeller to rotate.

[0012] The thrust measurement assembly includes a shaft, a force plate, and a thrust sensor; the shaft runs horizontally through the housing and can move in the horizontal direction; the force plate is connected to one end of the shaft inside the housing and faces the propeller, and the thrust sensor is connected to one end of the shaft outside the housing and fixed outside the housing; the propulsion load generated by the propeller is transmitted to the thrust sensor through the force plate and the shaft.

[0013] Furthermore, the dispensing port is located at the top of the box.

[0014] Furthermore, the dispensing surface of the dispensing port has a sloping structure.

[0015] Furthermore, the angle between the launch surface and the axis of the propeller is 40°-50°.

[0016] Furthermore, the housing is also provided with an observation window, which is located on the side of the propeller.

[0017] Furthermore, the drive mechanism includes a drive motor and at least one coupling.

[0018] Furthermore, the output end of the drive motor is connected to the rotating shaft via a belt, a coupling is mounted on the rotating shaft, and a propeller is installed at the end of the rotating shaft.

[0019] Furthermore, a torque sensor and / or a speed sensor are also provided between the coupling and the propeller.

[0020] Furthermore, the coupling is connected to the housing via a first sealing assembly to achieve a rotary seal.

[0021] Furthermore, the first sealing assembly includes a first bushing and a first sealing ring arranged coaxially.

[0022] Furthermore, the shaft and the housing are connected by a second sealing assembly to achieve a sliding seal.

[0023] Furthermore, the second sealing assembly includes a second bushing and a second sealing ring arranged coaxially.

[0024] Furthermore, the force-bearing plate is circular, and the diameter of the force-bearing plate is not less than the diameter of the propeller.

[0025] Furthermore, the diameter of the force-bearing plate is between 1.5 and 2.5 times the diameter of the propeller.

[0026] Furthermore, the distance between the force-bearing plate and the propeller is 1-3 times the diameter of the propeller.

[0027] Furthermore, the experimental apparatus also includes a temperature control component.

[0028] Furthermore, the temperature control assembly includes a temperature controller located inside the housing and a refrigeration compressor connected to the temperature controller.

[0029] The present invention also provides a propeller erosion test method, which uses the above-mentioned propeller erosion test apparatus, and the test method specifically includes the following steps:

[0030] S1: Place the propeller to be tested into the housing and connect it to the drive mechanism;

[0031] S2: The experimental medium simulating extreme environmental conditions is introduced into the chamber through the injection port;

[0032] S3: Adjust the temperature inside the chamber to the test temperature;

[0033] S4: Set up the high-speed camera and align it with the propeller, simultaneously start the high-speed camera and thrust sensor, and activate the drive mechanism to drive the propeller to rotate.

[0034] S5: Obtain the transient erosion morphology and thrust value of the propeller;

[0035] S6: Periodically replenish the experimental medium and obtain test results under different conditions.

[0036] Furthermore, in step S1, the experimental medium includes any one or a combination of water, ice, and gravel.

[0037] Furthermore, in step S3, the temperature is controlled between -60℃ and 0℃.

[0038] Furthermore, in step S4, torque and / or speed information can also be obtained through a torque sensor and / or a speed sensor.

[0039] Furthermore, when the shaft of the thrust measuring assembly is connected to the housing via a second sealing assembly, sealing friction compensation is required. The specific method is as follows:

[0040] With the propeller stationary, an axial calibrated tension is applied to the shaft and the thrust sensor readings are collected to calculate the sealing friction force.

[0041] Establish the calibration tension-friction compensation curve;

[0042] When formally measuring the propeller thrust, the corresponding friction compensation value is included based on the raw reading of the thrust sensor.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] (1) The propeller erosion test apparatus of the present invention places the propeller horizontally inside the box, and with the experimental medium released from the release port and the drive mechanism driving the propeller to rotate stably, it can reproduce the collision, cutting and blocking effects of the propeller with sea ice during propulsion in the horizontal direction, which significantly improves the consistency between the test results and the actual icebreaking operation stress conditions. In addition, the present invention uses a horizontally movable shaft in the thrust measurement component to transmit the propulsion load generated by the propeller to the thrust sensor outside the box via the force plate, which can capture thrust changes in real time and avoid the data deviation caused by the interference of gravity component in the traditional vertical structure.

[0045] (2) This invention uses horizontally installed propellers and periodically releases experimental media such as ice and gravel, combined with temperature control, to realistically reproduce the collision and cutting process between propellers and sea ice in polar seas, breaking through the limitations of traditional simulations; it can also be equipped with thrust, torque, and speed sensors to achieve multi-dimensional power parameter acquisition; the side observation window and high-speed camera work together to monitor the propeller surface and fluid dynamics in real time, providing a visual basis for the study of erosion mechanism, and constructing a highly controllable and comprehensive experimental platform, providing high-precision experimental support for the evaluation of the anti-icing performance of ship propellers and the study of material modification.

[0046] (3) The propeller erosion test device of the present invention can flexibly reproduce complex ice sand trajectories by horizontal propulsion and continuous slope delivery. The device is compact, the working conditions can be switched quickly, and the cost is significantly reduced.

[0047] (4) The propeller erosion test method of the present invention provides a high-fidelity simulation of the real polar marine environment. The water / ice / gravel multiphase medium reproduces the extreme ice load erosion conditions under controllable temperature, accurately simulates the blocking, cutting and collision process of the propeller with polar sea ice during horizontal propulsion, and truly reflects the stress situation of the propeller in actual icebreaking operations.

[0048] (5) The propeller erosion test method of the present invention can also provide full-parameter dynamic correlation analysis, such as high-speed camera and multi-level sensor synchronous triggering to construct the real-time mapping relationship between the transient erosion morphology of the propeller and thrust / torque / speed, providing high-precision experimental support for subsequent research on the anti-icing performance evaluation and material modification of ship propellers. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the overall structure of the propeller erosion experimental device of the present invention.

[0050] Figure 2 This is a schematic diagram of the internal structure of the propeller erosion experimental device of the present invention.

[0051] Figure 3 This is a schematic diagram of the drive mechanism in Embodiment 3 of the present invention.

[0052] Figure 4 This is a schematic diagram of the thrust measurement component of the present invention.

[0053] Figure 5 This is a photograph of the propeller taken in Embodiment 9 of the present invention.

[0054] Figure 6 This is the tension-friction compensation curve in Embodiment 9 of the present invention.

[0055] Figure 7 This is the time-temperature curve in Embodiment 9 of the present invention.

[0056] Figure 8 This is the time-thrust curve in Embodiment 9 of the present invention.

[0057] Figure 9 This is the time-torque curve in Embodiment 9 of the present invention.

[0058] Explanation of markings in the diagram:

[0059] 1-Propeller;

[0060] 2-Box body, 21-Dispensing port, 22-Observation window, 23-Open / close door;

[0061] 3-Drive mechanism, 31-Drive motor, 32-Coupling, 33-Belt, 34-Shaft, 35-Bearing housing;

[0062] 4-Thrust measurement assembly, 41-Shaft, 42-Force plate, 43-Thrust sensor, 44-Fixed component;

[0063] 5-First sealing assembly, 51-First bushing, 52-First sealing ring;

[0064] 6-Second sealing assembly, 61-Second bushing, 62-Second sealing ring;

[0065] 7-Temperature control component, 71-Temperature controller, 72-Refrigeration compressor;

[0066] 8-Supporting platform. Detailed Implementation

[0067] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0068] In this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, or integral connections; they can be mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; they can be internal connections between two elements. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0069] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0070] To test the erosion corrosion characteristics of propellers under simulated polar conditions, the first aspect of this invention provides a propeller erosion experimental apparatus. The apparatus includes a housing, a drive mechanism, and a thrust measurement component. The propeller to be tested is horizontally positioned within the housing. The housing has an inlet for introducing experimental media into the housing. The drive mechanism is located outside the housing, connected to the propeller, and used to drive the propeller to rotate. The thrust measurement component includes a shaft, a force plate, and a thrust sensor. The shaft horizontally penetrates the housing and is movable in a horizontal direction. The force plate is connected to one end of the shaft inside the housing and faces the propeller. The thrust sensor is connected to one end of the shaft outside the housing and fixed outside the housing. The propulsive load generated by the propeller is transmitted to the thrust sensor via the force plate and the shaft.

[0071] In some specific implementations, the dispensing port is located at the top of the box.

[0072] In some specific embodiments, the dispensing surface of the dispensing port has a sloping structure.

[0073] In some more specific embodiments, the angle between the launch surface and the axis of the propeller is 40°-50°.

[0074] In some specific embodiments, the housing is also provided with an observation window, which is located on the side of the propeller.

[0075] In some specific embodiments, the drive mechanism includes a drive motor and at least one coupling.

[0076] In some more specific embodiments, the output end of the drive motor is connected to the shaft via a belt, a coupling is disposed on the shaft, and a propeller is mounted on the end of the shaft.

[0077] In some more specific embodiments, a torque sensor and / or a speed sensor are also provided between the coupling and the propeller.

[0078] In some specific embodiments, the coupling is connected to the housing via a first sealing assembly to achieve a rotary seal.

[0079] In some more specific embodiments, the first sealing assembly includes a first bushing and a first sealing ring arranged coaxially.

[0080] In some specific embodiments, the shaft and the housing are connected by a second sealing assembly to achieve a sliding seal.

[0081] In some more specific embodiments, the second sealing assembly includes a second bushing and a second sealing ring arranged coaxially.

[0082] In some specific embodiments, the force-bearing plate is circular, and the diameter of the force-bearing plate is not less than the diameter of the propeller.

[0083] In some more specific embodiments, the diameter of the force-bearing plate is between 1.5 and 2.5 times the diameter of the propeller.

[0084] In some specific embodiments, the distance between the force-bearing plate and the propeller is 1-3 times the diameter of the propeller.

[0085] In some specific embodiments, the experimental apparatus also includes a temperature control component.

[0086] In some more specific embodiments, the temperature control assembly includes a temperature controller located inside the housing and a refrigeration compressor connected to the temperature controller.

[0087] A second aspect of the present invention provides a method for testing propeller erosion, using the aforementioned propeller erosion testing apparatus, the method specifically comprising the following steps:

[0088] S1: Place the propeller to be tested into the housing and connect it to the drive mechanism;

[0089] S2: The experimental medium simulating extreme environmental conditions is introduced into the chamber through the injection port;

[0090] S3: Adjust the temperature inside the chamber to the test temperature;

[0091] S4: Set up the high-speed camera and align it with the propeller, simultaneously start the high-speed camera and thrust sensor, and activate the drive mechanism to drive the propeller to rotate.

[0092] S5: Obtain the transient erosion morphology and thrust value of the propeller;

[0093] S6: Periodically replenish the experimental medium and obtain test results under different conditions.

[0094] In some specific implementations, in step S1, the experimental medium includes any one or more combinations of water, ice, and gravel.

[0095] In some specific implementations, in step S3, the temperature is controlled between -60°C and 0°C.

[0096] In some specific implementations, in step S4, torque and / or speed information can also be obtained through a torque sensor and / or a speed sensor.

[0097] In some specific embodiments, when the shaft of the thrust measuring component is connected to the housing via a second sealing component, sealing friction compensation is required. The specific method is as follows:

[0098] With the propeller stationary, apply an axial calibration tension to the shaft and collect thrust sensor readings to calculate the sealing friction force; establish a calibration tension-friction force compensation curve; when formally measuring the propeller thrust, incorporate the corresponding friction force compensation value based on the original thrust sensor readings.

[0099] Each of the above embodiments can be implemented individually, or in any combination of two or more. The following detailed description of specific examples will further illustrate these embodiments.

[0100] Example 1:

[0101] This embodiment provides a propeller erosion experimental apparatus for testing the erosion corrosion characteristics of propeller 1 under simulated polar conditions. Figure 1-2 As shown, the experimental apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4. The propeller 1 to be tested is horizontally arranged inside the housing 2.

[0102] In this embodiment, the housing 2 is provided with a dispensing port 21 for dispensing experimental media into the housing 2, thereby simulating extreme environmental conditions by dispensing experimental media.

[0103] The drive mechanism 3 of this embodiment is located outside the housing 2 of this embodiment. It is connected to the propeller 1 and is used to drive the propeller 1 to rotate.

[0104] The thrust measurement assembly 4 in this embodiment includes a shaft 41, a force plate 42, and a thrust sensor 43. The shaft 41 horizontally penetrates the housing 2 and can move horizontally. The force plate 42 is connected to the end of the shaft 41 located inside the housing 2 and faces the propeller 1. The thrust sensor 43 is connected to the end of the shaft 41 located outside the housing 2 and is fixed to the outside of the housing 2. In this embodiment, the propulsive load generated by the propeller 1 is transmitted to the thrust sensor 43 through the force plate 42 and the shaft 41.

[0105] In this embodiment, the propeller 1 is horizontally positioned inside the housing 2. Combined with the experimental medium dispensed through the inlet 21 and the stable rotation of the propeller 1 by the drive mechanism 3, the collision, cutting, and blocking effects of the propeller 1 against sea ice during propulsion can be reproduced in the horizontal direction, significantly improving the consistency between the experimental results and the actual stress conditions during icebreaking operations. Through the horizontally movable shaft 41 in the thrust measurement assembly 4, the propulsive load generated by the propeller 1 is transmitted via the force plate 42 to the thrust sensor 43 outside the housing 2. This allows for real-time capture of thrust changes and avoids data deviations caused by gravitational interference in traditional vertical structures.

[0106] Example 2:

[0107] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0108] The difference from Example 1 is that the injection port 21 in this example is located at the top of the housing 2. In order to better disperse the experimental medium and reduce the direct impact on the propeller 1, the injection surface of the injection port 21 has a sloping structure, and the angle formed between the injection surface and the axis of the propeller 1 is 40°-50°.

[0109] To facilitate observation of the erosion morphology of the propeller 1 in the experimental medium, the housing 2 of this embodiment is also provided with an observation window 22. The observation window 22 is located on the side of the propeller 1 in this embodiment, which is convenient for observation with the naked eye or image acquisition by a camera or other device. The observation window 22 can be made of transparent glass and forms a seal with the housing 2.

[0110] Example 3:

[0111] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0112] The difference from Embodiment 1 is that the drive mechanism 3 in this embodiment includes a drive motor 31 and at least one coupling 32. For example... Figure 3 As shown, in this embodiment, the output end of the drive motor 31 can be directly connected to the coupling 32, which is connected to the propeller 1 under test; or, depending on the device layout requirements, the output end of the drive motor 31 can be connected to the rotating shaft 34 via a belt 33, with the coupling 32 mounted on the rotating shaft 34, the propeller 1 mounted on the end of the rotating shaft 34, and the rotating shaft 34 supported and fixed by at least one bearing seat 35. Regardless of whether a direct or indirect transmission method is adopted, those skilled in the art can realize the drive mechanism 3 driving the propeller 1.

[0113] In order to further obtain the torque and / or speed of propeller 1 during the test, a torque sensor and / or speed sensor are also provided between the coupling 32 and propeller 1 in this embodiment. Combined with the thrust sensor 43, the mapping relationship between the transient erosion morphology of propeller 1 and the above physical data information can be constructed through the thrust / torque / speed data collected by the multi-level sensors.

[0114] Example 4:

[0115] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0116] The difference from Example 3 is that, as Figure 4 As shown, in this embodiment, the coupling 32 and the housing 2 are connected by a first sealing assembly 5 to achieve a rotary seal. Specifically, the first sealing assembly 5 includes a first bushing 51 and a first sealing ring 52 arranged coaxially, both mounted at the end of the coupling 32. The first sealing ring 51 is embedded within the wall thickness of the housing 2, and the first bushing 51 passes through the thickness direction of the housing 2 and connects with the first sealing ring 51.

[0117] Example 5:

[0118] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0119] The difference from Example 3 is that, as Figure 4 As shown, in this embodiment, the shaft 41 and the housing 2 are connected by a second sealing assembly 6 to achieve a sliding seal. The second sealing assembly 6 in this embodiment includes a second bushing 61 and a second sealing ring 62 arranged coaxially. The second sealing ring 61 is embedded in the wall thickness of the housing 2, and the second bushing 61 passes through the thickness direction of the housing 2 and connects with the second sealing ring 61.

[0120] Example 6:

[0121] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0122] The difference from Embodiment 3 is that the force plate 42 in this embodiment is circular, and the diameter of the force plate 42 is not less than the diameter of the propeller 1. The diameter of the force plate 42 is preferably between 1.5 and 2.5 times the diameter of the propeller 1. This reasonable range can ensure that the water flow will not flow around the edge of the force plate 42, and will not increase the fluid resistance due to the excessive size of the propeller 1.

[0123] In this embodiment, the distance between the force plate 42 and the propeller 1 is 1-3 times the diameter of the propeller 1. Maintaining a suitable distance range can make the fluid tend to be stable and will not lead to unstable force measurement.

[0124] Example 7:

[0125] This embodiment provides a propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, and a thrust measurement component 4, with the propeller 1 to be tested horizontally positioned inside the housing 2.

[0126] The difference from Embodiment 3 is that, in order to control the temperature inside chamber 2 to reach the simulated temperature under polar conditions, the experimental apparatus in this embodiment also includes a temperature control component 7. The temperature control component 7 specifically includes a temperature controller 71 located inside chamber 2, and a refrigeration compressor 72 connected to the temperature controller 71. The refrigeration compressor 72 is located outside chamber 2 and is used to provide cooling.

[0127] Example 8:

[0128] This embodiment provides a propeller erosion test apparatus and an erosion test method using the apparatus, for testing the erosion corrosion characteristics of a propeller 1 under simulated polar conditions. The test apparatus of this embodiment includes a housing 2, a drive mechanism 3, a thrust measurement component 4, a first sealing component 5, a second sealing component 6, and a temperature control component 7. The propeller 1 to be tested is horizontally arranged inside the housing 2.

[0129] In this embodiment, the top of the housing 2 is provided with a dispensing port 21 for dispensing experimental media into the housing 2 to simulate extreme environmental conditions. The dispensing surface of the dispensing port 21 has a sloping structure, and the angle formed between the dispensing surface and the axis of the propeller 1 is 40°-50°, so as to better disperse the experimental media and reduce the direct impact of the experimental media on the propeller 1. The housing 2 in this embodiment is also provided with an observation window 22, which is located on the side of the propeller 1 in this embodiment, so as to facilitate visual observation or observation of the erosion morphology of the propeller 1 in the experimental media through a camera.

[0130] The drive mechanism 3 of this embodiment is disposed outside the housing 2 of this embodiment. It is connected to the propeller 1 and is used to drive the propeller 1 to rotate. The drive mechanism 3 includes a drive motor 31 and at least one coupling 32. The output end of the drive motor 31 in this embodiment can be directly connected to the coupling 32, and the coupling 32 is connected to the propeller 1 to be tested; or, according to the needs of the device layout, the output end of the drive motor 31 is connected to the rotating shaft 34 through a belt 33, the coupling 32 is disposed on the rotating shaft 34, and the propeller 1 is mounted on the end of the rotating shaft 34. Regardless of whether a direct or indirect transmission method is adopted, those skilled in the art can realize the drive mechanism 3 to drive the propeller 1.

[0131] In this embodiment, the coupling 32, propeller 1, and thrust measurement component 4 are coaxially arranged to ensure that the propulsion load generated by the propeller 1 can be directly transmitted to the thrust measurement component 4.

[0132] In this embodiment, a torque sensor and / or a speed sensor are also provided between the coupling 32 and the propeller 1. These sensors can be combined with the thrust sensor 43 to construct a multi-level sensor system to collect thrust / torque / speed data during the test process.

[0133] In this embodiment, the coupling 32 is connected to the housing 2 via a first sealing assembly 5 to achieve a rotary seal. Specifically, the first sealing assembly 5 includes a first bushing 51 and a first sealing ring 52 arranged coaxially. The first sealing ring 51 is embedded within the wall thickness of the housing 2, and the first bushing 51 passes through the thickness direction of the housing 2 and connects with the first sealing ring 51.

[0134] The thrust measurement assembly 4 in this embodiment includes a shaft 41, a force plate 42, and a thrust sensor 43. The shaft 41 horizontally penetrates the housing 2 and can move horizontally. The force plate 42 is connected to one end of the shaft 41 inside the housing 2 and faces the propeller 1. The thrust sensor 43 is connected to the other end of the shaft 41 outside the housing 2 and is fixed to the outside of the housing 2. In this embodiment, the propulsive load generated by the propeller 1 is transmitted to the thrust sensor 43 via the force plate 42 and the shaft 41. The force plate 42 in this embodiment is circular, and its diameter is not less than the diameter of the propeller 1. Preferably, the diameter of the force plate 42 is between 1.5 and 2.5 times the diameter of the propeller 1. The distance between the force plate 42 and the propeller 1 is 1 to 3 times the diameter of the propeller 1. Maintaining a suitable distance range can stabilize the fluid and prevent unstable force measurement.

[0135] In this embodiment, the shaft 41 and the housing 2 are connected by a second sealing assembly 6 to achieve a sliding seal. The second sealing assembly 6 in this embodiment includes a second bushing 61 and a second sealing ring 62 arranged coaxially. The second sealing ring 61 is embedded in the wall thickness of the housing 2, and the second bushing 61 passes through the thickness direction of the housing 2 and connects with the second sealing ring 61.

[0136] The temperature control component 7 in this embodiment specifically includes a temperature controller 71 disposed inside the housing 2, and a refrigeration compressor 72 connected to the temperature controller 71. The refrigeration compressor 72 is disposed outside the housing 2 and is used to provide cooling capacity to control the temperature inside the housing 2 to reach the simulated temperature under polar conditions.

[0137] This embodiment uses the aforementioned propeller erosion test apparatus to conduct an erosion test on the propeller 1 to be tested. The erosion test method specifically includes the following steps:

[0138] S1: Place the propeller 1 to be tested into the housing 2 and connect it to the drive mechanism 3;

[0139] S2: The experimental medium simulating extreme environmental conditions is introduced into the chamber 2 through the injection port 21;

[0140] S3: Adjust the temperature inside chamber 2 to the test temperature;

[0141] S4: Set up the high-speed camera and aim it at the propeller 1, simultaneously start the high-speed camera and thrust sensor 43, and turn on the drive mechanism 3 to drive the propeller 1 to rotate.

[0142] S5: Obtain the transient erosion morphology and thrust value of the propeller;

[0143] S6: Periodically replenish the experimental medium and obtain test results under different conditions.

[0144] In step S1, the experimental medium includes any one or a combination of water, ice, and gravel.

[0145] In step S3, the temperature is controlled between -60℃ and 0℃ to simulate the polar environment.

[0146] In step S4, torque and / or speed information is acquired through a torque sensor and / or a speed sensor.

[0147] In this embodiment, since sealing friction compensation is required when the shaft 41 of the thrust measurement component 4 is connected to the housing 2 through the second sealing component 6, the specific method is as follows: When the propeller 1 is stationary, an axial calibration tension is applied to the shaft 41 and the reading of the thrust sensor 43 is collected to calculate the sealing friction force; a calibration tension-friction force compensation curve is established; when the thrust of the propeller 1 is formally measured, the corresponding friction force compensation value is included according to the original reading of the thrust sensor 43.

[0148] Example 9:

[0149] like Figure 1-4 As shown, this embodiment provides a propeller erosion test device, including a propeller 1, a housing 2, a drive mechanism 3, a thrust measurement component 4, and a support platform 8.

[0150] In this embodiment, the housing 2 is provided with a dispensing port 21 for dispensing experimental media into the housing 2. The propeller 1 is horizontally positioned inside the housing 2. The drive mechanism 3 is located outside the housing 2 and connected to the propeller 1 to drive the propeller 1 to rotate. The thrust measurement assembly 4 includes a shaft 41, a force plate 42, and a thrust sensor 43. The shaft 41 passes through the housing 2, with its first end located inside the housing 2 and its second end located outside the housing 2. The shaft 41 is capable of moving horizontally. The force plate 42 is connected to the first end and faces the propeller 1. The thrust sensor 43 is fixed to the outside of the housing 2 and contacts the second end.

[0151] In this embodiment, the housing 2 is also provided with a switch door 23 on the side where the thrust measuring component 4 is located, and the thrust measuring component 4 is located on the switch door 23. When it is necessary to install the propeller 1, the switch door 23 is opened; when it is necessary to inject experimental medium into the housing 2, the switch door 23 is closed; when it is necessary to discharge the experimental medium and remove the propeller 1, the switch door 23 is opened again.

[0152] By horizontally positioning the propeller 1 within the housing 2, and using the experimental medium dispensed through the inlet 21, the collision, cutting, and blocking effects of the propeller 1 against sea ice during propulsion can be reproduced horizontally, significantly improving the consistency between the experimental results and the actual stress conditions during icebreaking operations. Through the horizontally movable shaft 41 in the thrust measurement assembly 4, the propulsive load generated by the propeller 1 is transmitted via the force plate 42 to the thrust sensor 43 outside the housing 2, enabling real-time capture of thrust variation curves and avoiding data deviations caused by gravitational interference in traditional vertical structures. The housing 2, used in conjunction with the inlet 21, allows for the batch dispensing and recycling of the experimental medium. The drive mechanism 3 stably drives the propeller 1 to rotate at a constant or variable speed, ensuring accurate reproduction of the operating parameters (medium concentration, flow rate, rotational speed, and load) for each experiment, guaranteeing the consistency and comparability of the experimental results.

[0153] The propeller erosion experimental apparatus of this embodiment also includes a temperature controller 71, which is disposed inside the chamber 2 and used to control the temperature inside the chamber 2. The temperature controller 71 is connected to the refrigeration compressor 72.

[0154] In this embodiment, the injection port 21 has a sloping surface, with the angle between the injection surface and the axis of the propeller 1 being 40°-50°, specifically 45° in this embodiment. The sloping structure allows the injected experimental medium to acquire a lateral velocity component upon contact with the water surface inside the tank 2, achieving spatial pre-dispersion of the experimental medium. Compared to vertical injection, this design also avoids direct impact of experimental medium clumps on the propeller 1, preventing distortion in thrust measurement.

[0155] The drive mechanism 3 in this embodiment includes a drive motor 31 and a coupling 32. The coupling 32 passes through the housing 2, and the drive motor 31 is connected to the propeller 1 through the coupling 32. The propeller erosion experimental device in this embodiment also includes a torque sensor and a speed sensor, both of which are disposed between the coupling 32 and the propeller 1.

[0156] In this embodiment, the housing 2 is provided with an observation window 22, which is located on the side of the propeller 1.

[0157] In this embodiment, considering the reasonable layout of each component, a support platform 8 is also provided. The housing 2 is located on the support platform 8, and the refrigeration compressor 72 and the drive motor 31 are located at the bottom of the support platform 8.

[0158] The propeller erosion test apparatus of this embodiment also includes a first sealing assembly 5. The coupling 32 is connected to the housing 2 through the first sealing assembly 5 to achieve rotational sealing. The first sealing assembly 5 includes a first bushing 51 and a first sealing ring 52, which are installed at the end of the coupling 32.

[0159] The propeller erosion experimental apparatus of this embodiment also includes a second sealing assembly 6, through which the shaft 41 is connected to the housing 2. The second sealing assembly 6 includes a second bushing 61 and a second sealing ring 62, which are mounted on the shaft 41 to achieve a sliding seal. The second bushing 61 provides radial support to the shaft 41, ensuring that the thrust transmission path strictly coincides with the axis of the thrust sensor 43, reducing measurement deviations caused by lateral forces. The second sealing ring 62 undergoes uniform radial deformation under the constraint of the bushing, resulting in a better sealing effect.

[0160] In this embodiment, the force-bearing plate 42 is circular, and its diameter is larger than that of the propeller 1, which can accurately reflect the thrust of the propeller 1. Preferably, the diameter of the force-bearing plate 42 is between 1.5 and 2.5 times the diameter of the propeller 1, which can ensure that the water flow does not flow around the edge of the force-bearing plate 42 and that the size of the propeller 1 is not too large, thus increasing fluid resistance.

[0161] In this embodiment, the distance between the force-bearing plate 42 and the propeller 1 is between 1 and 3 times the diameter of the propeller 1, preferably 1.5 times. With a moderate distance between the force-bearing plate 42 and the propeller 1, the fluid tends to be stable and the kinetic energy loss of the fluid will not be too large, resulting in unstable force measurement or too small force measurement.

[0162] Since the shaft 41 needs to be sealed with a second sealing assembly 6, there will be sealing friction, which will cause a deviation in the actual measured thrust. Therefore, this embodiment also provides a sealing friction compensation method for measuring the thrust of the propeller 1, including:

[0163] (a) With the propeller 1 stationary, apply an axial calibration tension to the shaft 41 and collect the readings of the thrust sensor 43 to calculate the sealing friction force.

[0164] (b) Establish the calibration tension-friction compensation curve.

[0165] (c) When measuring the thrust of propeller 1, the corresponding friction compensation value is included based on the original reading of thrust sensor 43.

[0166] This embodiment also provides a method for conducting propeller erosion experiments using the above-described propeller erosion experimental apparatus. The experimental method includes:

[0167] (1) Add experimental media into the box 2 through the inlet 21. The experimental media include water, ice and gravel.

[0168] (2) Adjust the temperature inside the chamber 2 to 0℃.

[0169] (3) Set a high-speed camera outside the observation window 22 to aim at the propeller 1, and simultaneously start the high-speed camera, thrust sensor 43, torque sensor and speed sensor.

[0170] (4) Start the drive mechanism 3 to drive the propeller 1 to rotate. The speed of the propeller 1 is 200 revolutions per minute.

[0171] (5) Periodically replenish the experimental medium into the box 2 through the inlet 21.

[0172] The propeller erosion test method in this embodiment provides a high-fidelity simulation of the real polar marine environment. The water / ice / gravel multiphase medium reproduces the extreme ice load erosion conditions under controllable temperature, accurately simulates the blocking, cutting and collision process of propeller 1 with polar sea ice during horizontal propulsion, and truly reflects the stress situation of propeller 1 in actual icebreaking operations.

[0173] Based on real-world testing, the propeller photos captured by the camera in this embodiment are as follows: Figure 5 As shown, the propeller diameter used in this embodiment is 15 inches (≈0.381m).

[0174] Figure 6 The intercept of the tension-friction compensation curve during the test is the friction compensation value of shaft 41, which is 4.77N in this embodiment.

[0175] Figure 7 The graph shows the time-temperature curve during the test. As can be seen from the graph, the temperature remained relatively stable during the experiment, fluctuating within ±2℃ of the set temperature (0℃).

[0176] Figure 8 The time-thrust curve after taking into account the friction compensation value shows an average thrust of 21.27 N. The thrust calculated according to the following empirical formula for propeller thrust is 23.41 N. The measured thrust in this embodiment has a small error compared with the theoretically calculated thrust, which meets the experimental requirements and the experimental results are relatively reliable.

[0177] T=K T ρn 2 D 4 ;

[0178] Where: T is the propeller thrust (N), K T The thrust coefficient is 0.1 in this embodiment, and ρ is the fluid density, which is 1000 kg / m³ in this embodiment. 3n is the rotational speed (revolutions per second), and D is the propeller diameter (m).

[0179] Figure 9 The time-torque curve during the test shows an average torque of 4.7 N·m. The torque calculated using the following propeller torque formula is 4.5 N·m. The measured torque in this embodiment has a small error compared to the theoretically calculated torque, which meets the experimental requirements and the experimental results are relatively reliable.

[0180] Q = K Q ρn 2 D 5 ;

[0181] Where: Q is the propeller torque (N·m), K Q The torque coefficient is 0.05 in this embodiment, and ρ is the fluid density, which is 1000 kg / m³ in this embodiment. 3 n is the rotational speed (revolutions per second), and D is the propeller diameter (m).

[0182] As can be seen from the above test results, the propeller erosion test method in this embodiment can also provide full-parameter dynamic correlation analysis, such as synchronous triggering of high-speed camera and multi-level sensors to construct the real-time mapping relationship between the transient erosion morphology of the propeller and thrust / torque / speed, providing high-precision experimental support for subsequent research on the anti-icing performance evaluation and material modification of ship propellers.

[0183] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A propeller erosion test apparatus for testing the erosion corrosion characteristics of a propeller (1) under simulated polar conditions, characterized in that, The experimental device includes a housing (2), a drive mechanism (3) and a thrust measurement component (4), with the propeller (1) to be tested horizontally placed inside the housing (2); The box (2) is provided with a dispensing port (21) for dispensing experimental media into the box (2); The drive mechanism (3) is located outside the housing (2), and is connected to the propeller (1) and used to drive the propeller (1) to rotate; The thrust measurement assembly (4) includes a shaft (41), a force plate (42), and a thrust sensor (43); the shaft (41) passes horizontally through the housing (2) and can move in the horizontal direction; the force plate (42) is connected to one end of the shaft (41) inside the housing (2) and faces the propeller (1); the thrust sensor (43) is connected to one end of the shaft (41) outside the housing (2) and is fixed outside the housing (2); the propulsion load generated by the propeller (1) is transmitted to the thrust sensor (43) through the force plate (42) and the shaft (41).

2. The propeller erosion experimental apparatus according to claim 1, characterized in that, The dispensing port (21) is located on the top of the box (2); The launching surface of the launching port (21) is a sloping structure, and the angle between the launching surface and the axis of the propeller (1) is 40°-50°. The housing (2) is also provided with an observation window (22), which is located on the side of the propeller (1).

3. The propeller erosion experimental apparatus according to claim 1, characterized in that, The drive mechanism (3) includes a drive motor (31) and at least one coupling (32); The output end of the drive motor (31) is connected to the rotating shaft (34) via a belt (33), the coupling (32) is located on the rotating shaft (34), and the propeller (1) is installed at the end of the rotating shaft (34); A torque sensor and / or speed sensor are also provided between the coupling (32) and the propeller (1).

4. The propeller erosion experimental apparatus according to claim 4, characterized in that, The coupling (32) is connected to the housing (2) by a first sealing assembly (5) to achieve a rotary seal; The first sealing assembly (5) includes a first bushing (51) and a first sealing ring (52) arranged coaxially.

5. The propeller erosion experimental apparatus according to claim 1, characterized in that, The shaft (41) and the housing (2) are connected by a second sealing assembly (6) to achieve a sliding seal; The second sealing assembly (6) includes a second bushing (61) and a second sealing ring (62) arranged coaxially.

6. The propeller erosion experimental apparatus according to claim 1, characterized in that, The force plate (42) is circular, and the diameter of the force plate (42) is not less than the diameter of the propeller (1); The distance between the force plate (42) and the propeller (1) is 1-3 times the diameter of the propeller (1).

7. The propeller erosion experimental apparatus according to claim 1, characterized in that, The experimental apparatus also includes a temperature control component (7); The temperature control component (7) includes a temperature controller (71) located inside the housing (2) and a refrigeration compressor (72) connected to the temperature controller (71).

8. A method for testing propeller erosion, characterized in that, The propeller erosion test apparatus according to any one of claims 1-7 is used, and the test method specifically includes the following steps: S1: Place the propeller (1) to be tested inside the housing (2) and connect it to the drive mechanism (3); S2: Experimental media simulating extreme environmental conditions are introduced into the box (2) through the injection port (21); S3: Adjust the temperature inside the chamber (2) to the test temperature; S4: Set up a high-speed camera and aim it at the propeller (1), start the high-speed camera and thrust sensor (43) simultaneously, and turn on the drive mechanism (3) to drive the propeller (1) to rotate. S5: Obtain the transient erosion morphology and thrust value of the propeller; S6: Periodically replenish the experimental medium and obtain test results under different conditions.

9. The propeller erosion test method according to claim 8, characterized in that, In step S1, the experimental medium includes any one or more combinations of water, ice, and gravel; In step S3, the temperature is controlled between -60℃ and 0℃; In step S4, torque and / or speed information can also be obtained through a torque sensor and / or a speed sensor.

10. The propeller erosion test method according to claim 8, characterized in that, When the shaft (41) of the thrust measuring component (4) is connected to the housing (2) through the second sealing component (6), sealing friction compensation is required. The specific method is as follows: With the propeller (1) stationary, an axial calibration tension is applied to the shaft (41) and the reading of the thrust sensor (43) is collected to calculate the sealing friction force; Establish the calibration tension-friction compensation curve; When formally measuring the thrust of the propeller (1), the corresponding friction compensation value is calculated based on the original reading of the thrust sensor (43).

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