Ice damage test method based on cooperation of high-speed submerging jet flow and mechanical shock

Abstract

The invention provides a high-speed submerging jet flow and mechanical shock synergistic ice damage test method. The method comprises the following test steps: S1, arranging a data acquisition system; s2, initializing working conditions; s3, preparing an ice body sample; s4, prefabricating ice body damage by high-pressure water jet; s5, a servo electric cylinder drives a mechanical structure to impact ice damage; s6, data acquisition; and S7, data processing. According to the invention, the force sensor, the laser displacement sensor and the high-speed camera synchronously collect the load, deformation and image information of ice damage caused by impact of a mechanical structure by means of the servo electric cylinder under the jet-assisted effect, so that accurate control and synchronous measurement of submerged jet and mechanical cooperative damage are realized; the impact of different mechanical structures at different speeds on the ice damage load is avoided.

Description

Technical Field

[0001] This application relates to the field of ice damage testing technology, and in particular to a method for testing ice damage by combining high-speed submerged jet and mechanical impact. Background Technology

[0002] The problem of ice damage to mechanical structures has strong nonlinear and complex characteristics, making it difficult to analyze accurately using theory. The accuracy of numerical simulation cannot be verified at present. Therefore, experiments have become a reliable and efficient analytical method for the problem of ice damage to mechanical structures.

[0003] Structural impact ice damage tests are commonly used to study the impact loads during the ice damage process. However, existing test methods cannot accurately simulate the motion characteristics of ice damage in mechanical structures, cannot study the influence of underwater submerged jets on ice damage loads, cannot conduct in-depth analysis of crack propagation and ice damage mechanisms, and cannot guarantee the repeatability and accuracy of the tests. Summary of the Invention

[0004] This application provides a combined high-speed submerged jet and mechanical impact ice damage testing method to conduct in-depth analysis of crack propagation and ice damage mechanisms, and to ensure the repeatability and accuracy of the test.

[0005] The ice damage testing method combining high-speed submerged jet and mechanical impact provided in this application adopts the following technical solution: A method for testing ice damage by a combination of high-speed submerged jet and mechanical impact includes: S1. Deploy the data acquisition system; S2. Initialize the test conditions; S3. Prepare ice samples; S4. Start the high-pressure water pump and start the timer simultaneously. Use a constant temperature water jet to impact the bottom surface of the ice material. After the preset jet impact time is reached, stop the timer and turn off the high-pressure water pump. Take a picture to record the pre-damage image of the jet impact melting the ice body. S5. Trigger mechanical impact damage to ice material by impacting the ice material with a servo electric cylinder in single output mode or reciprocating output mode. S6. Data acquisition: The impact load changes during mechanical impact are measured by a load force sensor; the deformation of the upper surface of the ice material in the vertical direction during impact is collected by a laser displacement sensor; and the crack evolution of the upper surface of the ice material during impact is collected by a high-speed camera. S7. Data processing.

[0006] Furthermore, in step S5, the servo electric cylinder includes a servo motor, a reducer, a lead screw transmission mechanism, and an encoder. The servo driver controls the speed and torque of the servo motor, and the lead screw transmission mechanism converts the rotational motion output by the servo motor into the moving speed and output force of the impact head.

[0007] Furthermore, in step S5, the single output mode is to input the speed after setting the upper limit of the servo motor torque. If the speed exceeds the preset torque during the impact process, the speed will drop to zero. The speed will remain at zero for 2 seconds and then automatically jump out of the pause, or pause at the upper limit position, which is used to simulate the single uniform speed impact process of the mechanical structure. The reciprocating output mode is such that if the preset torque is exceeded and the speed is zero during the impact process, and the target position is not reached, it will return to the initial point and re-trigger until the target position is reached. This is used to simulate the continuous impact ice damage process after a single impact failure.

[0008] Furthermore, in step S6, when mechanical structure impact damage to ice is triggered, the data acquisition system is simultaneously triggered to capture the load, surface vertical deformation, and ice material crack evolution images during the impact damage process of the impact head, while saving and recording the output speed, torque, and position variables of the servo driver of the servo electric cylinder.

[0009] Furthermore, in steps S4 and S5, when performing jet pre-damage, it is possible to choose whether to trigger synchronously with mechanical impact. If it is triggered synchronously, the impact action is performed at the same time as the jet damage pre-damage is performed. Otherwise, a delay needs to be set according to the jet time, and the impact action is performed again after the jet damage action is completed. During the impact action, the system selects whether to perform multiple impacts based on the impact mode settings. If it is a single-impact mode, the test ends after the impact action is performed. If it is a multiple-impact mode, the degree of damage is judged in combination with the programming logic control strategy. If the damage is not complete, the impact action is repeated until the ice material is completely damaged and the test ends.

[0010] Furthermore, in step S7, the obtained load force change time history curve, vertical deformation of the ice surface at typical locations, output force of the servo electric cylinder, displacement, and other data are matched with the images captured by the high-speed camera to obtain the motion characteristics of the mechanical structure impacting ice damage process and the structural response of the ice body when impacted, for analysis of the process law of mechanical structure impacting ice damage.

[0011] Furthermore, in step S7, the vertical deformation of the ice material surface is divided into deformation before the ice material is damaged and failed and vertical displacement after failure. The focus is on the flexural deformation of the ice material under the action of the central load before the ice material is damaged and failed, so as to obtain the ultimate flexural deformation before the ice material breaks at a typical location. Based on the boundary constraint conditions, the complete flexural function is then solved by undetermined coefficients to obtain the global flexural deformation and stress distribution. The displacement data of the servo electric cylinder, combined with the peak load of the time-history load force, is used to determine the degree and difficulty of ice damage. The crack evolution image of ice material is binarized to eliminate background noise and other interference factors and then normalized. After calibrating the size, the crack propagation length, rate, direction and splitting crack complexity are calculated, and the correlation between peak load and crack energy release path is analyzed.

[0012] Furthermore, the load force at which the ice material reaches complete damage is optimized to reduce the peak load of the time-history load, which can then be used as the mechanical impact load in practical applications. Furthermore, by adjusting the impact speed of the servo electric cylinder, replacing the impact head, adjusting the jet target distance, and adjusting the nozzle type, the above steps S1 to S7 were repeated to investigate the effects of different conditions on the motion characteristics of the mechanical structure and the structural damage of the ice material; and Repeat steps S1, S2, S3, S5, S6, and S7, and conduct experiments to compare the results with steps S1 to S7 to investigate the contribution of jet action to impact ice damage.

[0013] Furthermore, in step S2, initializing the test conditions includes cooling the ambient fluid and jet fluid of the test conditions to the required temperature; and installing and adjusting the impact head, jet impact target distance and jet nozzle. Different types of impact heads are installed under the ice material according to the test requirements, and different jet target distances and nozzles are arranged.

[0014] In summary, this application includes at least one of the following beneficial technical effects: 1. This application proposes a detailed method and specific process logic for the synergistic ice damage caused by submerged jet and mechanical impact, and proposes a method for initializing test conditions to ensure the consistency of test conditions; 2. A precise control method for motion devices is proposed. By precisely controlling the output torque of the servo driver, the motion and dynamic parameters of the mechanical structure can be controlled, enabling impact tests on different mechanical structures under all motion conditions. 3. A synchronous measurement method was proposed, which uses the synchronous acquisition of parameters such as structural impact load, surface vertical deformation, ice material crack evolution image, and real-time velocity, output force, and displacement of mechanical structure impact to quantitatively analyze the damage law of ice caused by mechanical structure impact. 4. A non-contact deformation measurement method was proposed, which used a laser displacement sensor to collect the vertical deformation of the surface, realizing non-contact deformation measurement and avoiding damage to the original strength of the ice material by the strain gauge. This provides a new path for high-precision deformation measurement in ice damage tests. 5. A jet-assisted ice damage test method was proposed, which integrates jet-assisted ice damage techniques to study the influence of jet on ice damage load, thereby studying the synergistic effect of jet-assisted ice damage. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a flowchart of the test method according to an embodiment of this application; Figure 2 This is a schematic diagram of the overall structure of the test platform according to an embodiment of this application; Figure 3 This is a front view of the test platform according to an embodiment of this application; Figure 4 This is a top view of the test platform according to an embodiment of this application; Figure 5 This is a schematic diagram of the preset jet time reference method according to an embodiment of this application; Figure 6 This is a flowchart illustrating the test mode discrimination logic of an embodiment of this application; Figure 7 This is a schematic diagram of the digital data analysis principle of an embodiment of this application; a is a schematic diagram of the deformation of ice material at different times, b is a coordinate graph showing the relationship between the amount of flexural deformation and the impact time, c is a coordinate graph showing the relationship between the displacement of the impact head and the impact time, and d is a coordinate graph showing the relationship between the load on the impact head and the impact time. Figure 8 This is a schematic diagram of the image data analysis principle in an embodiment of this application; a is the mechanical impact mode without jet pre-damage, and b is the mechanical impact mode with jet pre-damage.

[0017] Figure label: 1. Load force sensor; 2. Laser displacement sensor; 3. High-speed camera; 4. Impact head; 5. Jet generator; 6. Jet target distance lifting plate; 7. High-pressure water pump; 8. Submerged chamber; 9. Water tank; 10. Ice material clamping device; 11. Servo electric cylinder. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0019] Reference Figures 1 to 8 This application discloses a method for testing ice damage caused by a combination of high-speed submerged jet and mechanical impact, which includes the following steps: S1. Data Acquisition System Setup: First, install the load force sensor 1 at the lower part of the impact head 4. According to Newton's third law, the impact load on the ice material is equal to the load applied to the impact head 4. After installation, zero the load force sensor 1. Then, install an array of multiple laser displacement sensors 2 above the surface of the ice material. Use a plumb bob to calibrate the vertical drop point during installation of the laser displacement sensors 2. This is used to collect the deformation of typical positions on the upper surface of the ice material in the vertical direction during impact, serving as one of the quantitative indicators for verifying the numerical simulation. Next, install the high-speed camera 3 above the surface of the ice material. Adjust the height, depth of field, and aperture of the high-speed camera 3 to capture a complete image of the ice surface and clearly identify the crack evolution on the upper surface of the ice material during impact. Finally, synchronously trigger and connect the load force sensor 1, laser displacement sensor 2, and high-speed camera 3.

[0020] S2. Initialize test conditions: First, install the impact head 4 required for the test on the load sensor 1 to ensure vertical stability and avoid eccentric damage. Install the jet nozzle of the required specification at the required position on the jet generator 5. Adjust the jet target distance lifting plate 6 to the required target distance. Connect the power pipeline between the jet generator 5 and the high-pressure water pump 7. Then fill the submerged chamber 8 and water tank 9 with water and cool them to the ambient fluid temperature and jet fluid temperature required for the predetermined working conditions to ensure that the external conditions of the test are uniform.

[0021] S3. Prepare ice samples: Prepare a batch of ice materials in advance, grind the surface of the same batch of ice materials to make it smooth, measure the thickness of the specimen, strictly control the surface smoothness of the same batch of ice material samples, transfer ice materials of uniform specifications to a 0 degree Celsius environment for slow temperature for 24 hours, and then transport and install them on the impact test bench in sequence. Use ice material clamping device 10 to clamp and pre-tighten the ice materials to simulate the continuous ice material structure.

[0022] S4. Start the high-pressure water pump: Before starting the high-pressure water pump 7, record the current temperature of the submerged chamber 8 and the water tank 9, calculate the pumping flow rate matched with the nozzle, and start the high-pressure water pump 7 and start the timer. Water at a constant temperature is pressurized by the high-pressure water pump and sprayed out from the nozzle at a certain position under the ice, continuously impacting, striking and dissolving the bottom surface of the ice material; after the preset jet impact time is reached, close the outlet valve of the high-pressure water pump 7, stop the timer, and the high-speed camera 3 takes pictures to record the pre-damage image of the jet impact melting the ice body.

[0023] Regarding the preset jet impact time in step S4, it is difficult to directly or indirectly assess the degree of jet damage to the ice material at a certain moment during the experiment. Therefore, it is necessary to conduct a small-scale jet damage to ice material pre-experiment before the actual experiment to obtain the variation law of jet damage to ice material dimensions over time. Figure 5 As shown, it is necessary to obtain in advance the typical damage level corresponding to the jet time variation under the required test jet target distance and nozzle type. Figure 5 The vertical axis H represents the jet damage depth, the horizontal axis D represents the jet damage range, and the horizontal axis t represents the jet impact time; for example, t 10 At time t, the jet damage depth corresponds to 10% of the ice material thickness, and so on. 25 , t 50 , t 100 The corresponding jet damage depths are 25%, 50%, and 100% of the ice material thickness, respectively. During the test, the jet damage depth is controlled by adjusting the preset jet impact time.

[0024] S5. Triggering Mechanical Structure Impact Ice Damage: During the mechanical structure impact ice damage process, the impact head 4 is driven by the servo electric cylinder 11 to perform a vertical impact action. The servo electric cylinder 11 consists of a servo motor, a reducer, a lead screw transmission mechanism, and an encoder. The speed and torque of the servo motor can be controlled by the servo driver, and converted into the moving speed and output force of the mechanical structure through the transmission mechanism, thereby realizing the impact action control of the impact head 4. That is, it can realize the mechanical structure impact action under all working conditions, such as uniform speed, acceleration and deceleration. The impact speed of the impact head 4 is set, and the servo driver is controlled by the PLC. The servo driver controls the speed and torque of the servo motor. Before triggering the impact head 4 to perform the ice damage action, the impact head 4 is first returned to the set origin position. After triggering, the real-time speed, torque, and position of the servo motor are recorded.

[0025] The execution speed, output force, and impact displacement of the impact head 4 can be calculated, as follows.

[0026] The execution speed can be determined based on the motor speed, lead screw lead, and reduction ratio. The specific calculation formula is as follows:

[0027] In the formula, V: execution speed, in mm / s; V m Motor speed, in rpm; L: Lead of the lead screw, in mm; R: Reduction ratio.

[0028] Furthermore, the output force can be calculated from the feedback torque of the servo motor.

[0029] In the formula, F: output force of servo electric cylinder 11, in kN; T: Servo motor output torque, in N·m; N: Output efficiency after removing system losses.

[0030] Furthermore, the impact displacement is determined by feeding back the initial and changing positions of the servo motor from the absolute encoder.

[0031] In the formula, Δx: impact displacement of the impact head 4, in mm; n: absolute position of the encoder, n i n0 is the current absolute position of the encoder, and n0 is the initial absolute position of the encoder. p: Number of pulses sent per revolution of the motor.

[0032] In addition, the PLC's built-in program control includes: return to origin and limit protection, single output mode, and reciprocating output mode. The return to origin and limit protection function ensures that the initial position of the impact head 4 remains consistent, and the limit protection prevents the impact head 4 from exceeding its range. The single output mode refers to setting a torque upper limit and inputting a speed. During the impact process, if the preset torque is exceeded, the speed decreases to zero, remains at zero speed for 2 seconds, and then automatically pauses, or pauses at the upper limit position, simulating a single uniform speed impact process of a mechanical structure. The reciprocating output mode refers to returning to the initial point and re-triggering if the target position is not reached when the preset torque is exceeded and the speed is zero during the impact process, until the target position is reached, simulating the continuous impact ice damage process after a single failed impact.

[0033] S6. Data Acquisition: Data acquisition uses a variable synchronous trigger mode. Before the ice damage action is triggered, data throughput is maintained, and the trigger conditions of load force sensor 1 and laser displacement sensor 2 are set. When the acquired data exceeds the set threshold, the principle of trigger lag is considered, and the test data starting from 1 second before the trigger is recorded and saved. This process also synchronously triggers high-speed camera 3 to realize synchronous capture of the load, surface vertical deformation, and ice material crack evolution images during the impact ice damage process of mechanical structure 4. In addition, this process also continuously records and saves the servo drive output speed, torque, and position variables of servo electric cylinder 11.

[0034] In some embodiments, steps S2 to S6 can be combined Figure 6 The specific process logic is as follows: After preparing the ice damage test prerequisites and setting parameters such as mechanical impact mode, impact velocity, and output force, first consider whether jet action coordination is required. If not, directly execute the impact action. If the test requires jet action coordination for ice damage, then the jet target distance, jet duration, and jet flow rate parameters need to be determined. When performing jet pre-damage, it is possible to choose whether to trigger synchronously with mechanical impact. If synchronous triggering is selected, the impact action is executed simultaneously with the jet damage pre-damage; otherwise, a delay needs to be set according to the jet time, and the impact action is executed again after the jet damage action is completed.

[0035] During the impact action, the system selects whether to perform multiple impacts based on the impact mode settings. If it is a single-impact mode, the test ends after the impact action is performed. If it is a multiple-impact mode, the degree of damage is judged in combination with the programming logic control strategy. If the damage is not complete, the impact action is repeated until the ice material is completely damaged and the test ends.

[0036] S7. Data Processing: By matching the obtained load force change time history curve, vertical deformation of the ice surface at typical locations, output force of servo electric cylinder 11, impact displacement, and other data with the images captured by high-speed camera 3, the motion characteristics of mechanical structure 4 during the impact on ice damage process and the structural response of ice body under impact can be obtained. This data can be used for process law analysis of mechanical structure 4 impact on ice damage. Quantitative data can be used to fit the motion characteristics of mechanical structure 4 and the structural failure law of ice material. In addition, it can also be used as experimental verification data for numerical simulation.

[0037] The typical location involves the vertical deformation of the ice surface, the displacement data processing of the servo electric cylinder 11, and its application. Figure 7 Detailed explanation. Surface vertical deformation is divided into deformation before ice material damage and failure, and vertical displacement after failure. Of particular focus is the deformation before the ice material fractures and breaks through the damage failure zone. Figure 7In the values ​​of a and b, at times t0 to t1, the ice material undergoes flexural deformation under the central load during these times. Based on this, the ultimate flexural deformation d before fracture at a typical location of the ice material can be obtained. i By combining the circular plate and its boundary constraints, the complete deflection function is solved by undetermined coefficients to obtain the global deflection deformation and stress distribution. The ultimate deflection deformation d0-d1 at time t1 is taken as one of the quantitative indicators of the strength of ice materials.

[0038] The displacement data of the servo electric cylinder 11 is determined by the initial position x0 and current position x1 of the impact head 4 on the servo motor, fed back by an absolute encoder. See [link / reference]. Figure 7 In this context, a, c, and Δx are important criteria for determining whether ice damage is successful. Δx = x i -x0 = 0, the ice material was not damaged; 0 < Δx = x i -x0≤ material thickness×50%, the ice material suffers minor damage; Material thickness × 50% < Δx = x i -x0≤ material thickness×100%, the ice material is severely damaged; Δx = x i -x0 > Material thickness × 100%, the ice material is completely damaged.

[0039] In general, ice materials can reach complete damage, therefore it is necessary to optimize the load force for complete damage. See [reference needed]. Figure 7 In the context of d, the preferred principle is to reduce the peak load F of the time-history load force. peak And a single peak load F peak It usually occurs simultaneously with ultimate flexural deformation, i.e., between time t1 and t2, and corresponds to the crack evolution stage of ice materials. This can be combined with... Figure 8 The crack evolution images captured by the medium-to-high-speed camera 3 at different times are further explained in detail. First, the crack evolution images of the ice material are binarized to eliminate background noise and other interference factors, and then normalized. After calibration, the crack propagation length l is calculated. i speed v i The direction and complexity of the splitting cracks.

[0040] right Figure 8 The a-type jetless pre-damage mechanical impact mode and Figure 8 A comparison was made between the b-jet pre-induced damage and the mechanical impact mode, where the crack propagation rate v was... i =(l i - l i-1The complexity of the splitting crack is determined by visual inspection and used to analyze the correlation between the peak load and the crack energy release path.

[0041] Furthermore, by adjusting the impact velocity of the impact head 4, replacing the impact head 4, adjusting the jet target distance, and adjusting the nozzle type, and repeating steps S1 to S7, the effects of different conditions on the motion characteristics of the mechanical structure 4 and the structural damage of the ice material can be investigated. Additionally, steps S1, S2, S3, S5, S6, and S7 can be repeated and compared with steps S1 to S7 to investigate the contribution of the jet effect to impact ice damage.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing ice damage by a combination of high-speed submerged jet and mechanical impact, characterized in that, include: S1. Deploy the data acquisition system; S2. Initialize the test conditions; S3. Prepare ice samples; S4. Start the high-pressure water pump and start the timer simultaneously. Use a constant temperature water jet to impact the bottom surface of the ice material. After the preset jet impact time is reached, stop the timer and turn off the high-pressure water pump. Take a picture to record the pre-damage image of the jet impact melting the ice body. S5. Trigger mechanical impact damage to ice material by impacting the ice material with a servo electric cylinder in single output mode or reciprocating output mode. S6. Data acquisition: The impact load changes during mechanical impact are measured by a load force sensor; the deformation of the upper surface of the ice material in the vertical direction during impact is collected by a laser displacement sensor; and the crack evolution of the upper surface of the ice material during impact is collected by a high-speed camera. S7. Data processing.

2. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 1, characterized in that, In step S5, the servo electric cylinder includes a servo motor, a reducer, a lead screw transmission mechanism, and an encoder. The servo driver controls the speed and torque of the servo motor, and the lead screw transmission mechanism converts the rotational motion output by the servo motor into the moving speed and output force of the impact head.

3. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 2, characterized in that, In step S5, the single output mode is to input the speed after setting the upper limit of the servo motor torque. If the speed exceeds the preset torque during the impact process, the speed will drop to zero. The speed will remain at zero for 2 seconds and then automatically jump out of the pause, or pause at the upper limit position, which is used to simulate the single uniform speed impact process of the mechanical structure. The reciprocating output mode is such that if the preset torque is exceeded and the speed is zero during the impact process, and the target position is not reached, it will return to the initial point and re-trigger until the target position is reached. This is used to simulate the continuous impact ice damage process after a single impact failure.

4. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 2, characterized in that, In step S6, when mechanical structure impact damage to ice is triggered, the data acquisition system is simultaneously triggered to capture the load, surface vertical deformation, and ice material crack evolution images during the impact damage process of the impact head, while saving and recording the output speed, torque, and position variables of the servo driver of the servo electric cylinder.

5. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 1, characterized in that, In steps S4 and S5, when performing jet pre-damage, it is possible to choose whether to trigger synchronously with mechanical impact. If it is triggered synchronously, the impact action is performed at the same time as the jet damage pre-damage is performed. Otherwise, a delay needs to be set according to the jet time, and the impact action is performed again after the jet damage action is completed. During the impact action, the system selects whether to perform multiple impacts based on the impact mode setting. If it is a single-execution mode, the test ends after the impact action is performed. If it is a multiple-execution mode, the degree of damage is judged by combining the programming logic control strategy; if it is not completely damaged, the impact action is repeated until the ice material is completely damaged and the test ends.

6. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 1, characterized in that, In step S7, the obtained load force change time history curve, vertical deformation of the ice surface at typical locations, output of the servo electric cylinder, displacement, and other data are matched with the images captured by the high-speed camera to obtain the motion characteristics of the mechanical structure impacting ice damage process and the structural response of the ice body when impacted, which is used for the process law analysis of mechanical structure impacting ice damage.

7. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 6, characterized in that, In step S7, the vertical deformation of the ice material surface is divided into deformation before the ice material is damaged and failed and vertical displacement after failure. The focus is on the flexural deformation of the ice material under the action of the central load before the ice material is damaged and failed, so as to obtain the ultimate flexural deformation before the ice material breaks at a typical location. Based on the boundary constraint conditions, the complete flexural function is then solved by undetermined coefficients to obtain the global flexural deformation and stress distribution. The displacement data of the servo electric cylinder, combined with the peak load of the time-history load force, is used to determine the degree and difficulty of ice damage. The crack evolution image of ice material is binarized to eliminate background noise and other interference factors and then normalized. After calibrating the size, the crack propagation length, rate, direction and splitting crack complexity are calculated, and the correlation between peak load and crack energy release path is analyzed.

8. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 7, characterized in that, The load force at which ice material reaches complete damage is optimized to reduce the peak load of the time-history load force, which can be used as the mechanical impact load in practical applications.

9. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 1, characterized in that, By adjusting the impact speed of the servo electric cylinder, replacing the impact head, adjusting the jet target distance, and adjusting the nozzle type, the above steps S1 to S7 were repeated to investigate the effects of different conditions on the motion characteristics of the mechanical structure and the structural damage of the ice material; and Repeat steps S1, S2, S3, S5, S6, and S7, and conduct experiments to compare the results with steps S1 to S7 to investigate the contribution of jet action to impact ice damage.

10. The method for testing ice damage by a combination of high-speed submerged jet and mechanical impact according to claim 1, characterized in that, In step S2, initializing the test conditions includes cooling the ambient fluid and jet fluid of the test conditions to the required temperature; and installing and adjusting the impact head, jet impact target distance and jet nozzle. Different types of impact heads are installed under the ice material according to the test requirements, and different jet target distances and nozzles are arranged.

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