Marine main engine fuel injector working performance evaluation method considering different vibration conditions

Abstract

The invention provides a marine main engine fuel injector working performance evaluation method considering different vibration conditions, and a matched evaluation experiment table is built. The evaluation process of the method comprises the steps that a to-be-detected oil injector is fixed to a bracket of an experiment table, vibration of different frequencies and amplitudes is generated through a vibration generator, meanwhile, the oil injector is connected through a high-pressure hose, and fuel oil is supplied; parameters such as valve opening pressure, fuel injection quantity and fuel trace area of the fuel injector under various vibration conditions are measured, then a performance aging judgment factor of the fuel injector is calculated, and according to the value range of the judgment factor, the performance aging degree of the fuel injector and whether further maintenance or replacement is needed or not are judged. Experiment conditions established by the method are closer to actual working conditions of mounting the fuel injector in the main engine, and important support is provided for reliability and safety of the marine main engine.

Description

Technical Field

[0001] The invention belongs to the technical field of ship equipment evaluation and maintenance, and in particular relates to a method for evaluating the working performance of a ship main engine injector taking into account different vibration conditions. Background Art

[0002] As the core of the ship's power system, the ship's main engine not only carries the task of propulsion, but is also directly related to the safe operation and efficient operation of the ship. As a key component of the main engine's fuel supply system, the injector's main function is to atomize the fuel and accurately spray it into the combustion chamber at the appropriate pressure and injection angle to achieve efficient combustion. Therefore, the working performance of the injector has an important impact on the stability, fuel efficiency and emission characteristics of the main engine.

[0003] In the process of testing and evaluating the working performance of the injector, traditional testing equipment often fails to fully consider the impact of vibration factors. During the operation of the ship, especially in low-frequency and high-frequency vibration environments, the structure of the injector will be subject to significant dynamic loads, and these loads may cause relative movement or wear of the internal components of the injector, thereby affecting its injection accuracy and atomization effect. However, many existing evaluation methods are mainly based on static testing, ignoring the vibration stress that the injector is subjected to under real working conditions, resulting in a gap between the performance evaluation results and the actual working status, which brings certain challenges to the evaluation of the health status of the injector.

[0004] During operation, the injector is subject to various vibrations from the host itself and the surrounding environment, including mechanical vibration, fluid vibration, etc. These vibration factors may cause fatigue damage to the internal components of the injector, which in turn causes the injector to fail or degrade in performance. For example, the injector seal may gradually age under repeated vibration shocks, resulting in seal failure, affecting the injection effect and combustion efficiency of the fuel. Therefore, it is particularly important to develop an evaluation method that can comprehensively consider the impact of vibration factors on the working performance of the injector.

[0005] By introducing the evaluation method of vibration analysis, we can more comprehensively understand the performance of the injector under actual working conditions, thus providing a more scientific basis for the maintenance and optimization of the injector. This not only helps to reduce the risk of failure caused by injector performance degradation, but also significantly improves the overall operating efficiency and reliability of the ship's main engine, ensuring safe and efficient navigation of the ship. Summary of the invention

[0006] The object of the present invention is to provide a method for evaluating the working performance of a fuel injector of a ship main engine taking into account different vibration conditions.

[0007] The technical solution adopted by the present invention is:

[0008] A test bench for evaluating the working performance of a fuel injector of a ship main engine taking into account different vibration conditions, the test bench comprising: a vibration controller, a camera, filter paper, a test box, a fuel injector to be evaluated, an electromagnetic vibrator in the right X-axis direction, a fuel injector mounting bracket, an electromagnetic vibrator in the upper Z-axis direction, a ventilation pipe, an explosion-proof ventilator, a high-pressure hose, an adjustable quantitative fuel injection pump, an oil suction pipe, a fuel tank, a filter, an electromagnetic vibrator in the rear Y-axis direction, an explosion-proof shadowless lamp, and a control station;

[0009] The injector to be evaluated is fastened to a mounting bracket, and the mounting bracket is suspended in the test box and fixed by connecting push rods of three electromagnetic exciters, and the three electromagnetic exciters are respectively an electromagnetic exciter in the right X-axis direction, an electromagnetic exciter in the rear Y-axis direction, and an electromagnetic exciter in the upper Z-axis direction, which are correspondingly mounted on the right side plate, the rear side plate, and the top plate inside the test box. The bottom plate of the test box is made of transparent material and the front cover plate can be opened. Filter paper is laid on the transparent bottom plate. When the injector sprays oil, the atomized oil droplets sprayed from each spray hole on the nozzle will form a spray oil trace corresponding to a single spray hole on the filter paper;

[0010] The suction port of the adjustable quantitative fuel injection pump is connected to the filter through an oil suction pipe, and the filter is completely immersed in the oil in the fuel tank. The discharge port of the adjustable quantitative fuel injection pump is connected to the injector to be evaluated through a high-pressure hose, and is also connected to the control station through a signal cable. The adjustable quantitative fuel injection pump has two working modes, manual and automatic. The default working mode is automatic. In this mode, the control station can receive instructions, automatically inhale and inject oil according to the set injection amount, and return injection parameters such as valve opening pressure;

[0011] The vibration controller is connected to the right side X-axis electromagnetic exciter, the rear side Y-axis electromagnetic exciter, the upper side Z-axis electromagnetic exciter and the control station through signal cables, receives vibration parameter setting instructions such as frequency and amplitude from the control station, and applies spatial vibration in the X-axis, Y-axis and Z-axis directions to the injector to be evaluated through the above (3) electromagnetic exciters;

[0012] The explosion-proof shadowless lamp is connected to the camera through a cable. The camera is arranged under the transparent bottom plate of the test box and connected to the control station through a signal cable. With the lighting assistance of the shadowless lamp, the camera calibrated with camera parameters can take pictures of the filter paper laid on the transparent bottom plate and transmit them to the control station. After image recognition, the parameters such as the spray oil trace area corresponding to each nozzle hole on the filter paper are automatically calculated. During the photo-taking process, the brightness of the explosion-proof shadowless lamp can be automatically adjusted as needed.

[0013] The ventilation pipe is connected to the opening at the top of the test box, and an explosion-proof fan is installed inside the ventilation pipe. The explosion-proof fan is connected to the control station through a signal cable. After each spraying experiment, the control station sends a start command to the explosion-proof fan to sweep the air for seconds to eliminate the residual oil mist in the test box.

[0014] The control station is connected to the vibration controller, the camera, the explosion-proof ventilator, and the adjustable quantitative fuel injection pump through a signal cable, and controls and coordinates the entire experimental platform by interacting with the above-mentioned devices for instructions and data;

[0015] The following steps are used to evaluate the injector performance using the above test bench:

[0016] The first step is to simulate the working environment of the ship main engine injector under vibration conditions. The specific steps are as follows: fix the injector to be evaluated on the mounting bracket in the test box, connect the injector to be evaluated and the adjustable quantitative injection pump with a high-pressure hose, then lay the filter paper on the transparent bottom plate in the test box and place the center of the filter paper directly below the nozzle. Next, set the injection amount Q, vibration frequency F and amplitude M on the control station. The control station communicates with the vibration controller and the adjustable quantitative injection pump through a signal cable, so that the vibration controller drives three electromagnetic exciters to work so as to apply spatial vibration in the X-axis, Y-axis and Z-axis directions, so that the adjustable quantitative injection pump automatically expels air, accumulates pressure, executes injection instructions and returns the valve opening pressure P;

[0017] The second step is to test the injection atomization parameters of the host injector under vibration conditions. The specific steps are as follows: the control station communicates with the camera and the explosion-proof ventilator through a signal cable, so that the explosion-proof shadowless lamp gives peak brightness during the injection atomization period, and the camera takes pictures and transmits them back. The control station uses the camera calibration parameters and image recognition technology to calculate the oil trace area corresponding to each injection hole, and finally obtains the oil trace areas A1, A2, ..., A corresponding to all λ injection holes of the injector to be evaluated under the conditions of injection amount Q, vibration frequency F, amplitude M and valve opening pressure P. λ Finally, the explosion-proof ventilator is controlled to start sweeping air and trigger a 15-second delay timer;

[0018] The third step is to calculate the performance aging factor ρ of the ship main engine injector under vibration conditions by the following formula:

[0019]

[0020] Where λ is the total number of injection holes of the injector, A max =max(A1, A2, ..., A λ ) represents the maximum value of the oil trace area of ​​the nozzle hole, A min =min(A1, A2, ..., A λ) represents the minimum value of the oil trace area of ​​the nozzle hole, A sum =sum(A1, A2, ..., A λ ) represents the sum of the oil trace areas of all nozzle holes, A avg =avg(A1, A2, ..., A λ ) represents the average value of the oil mark area of ​​the nozzle hole, represents the standard deviation of the oil trace area of ​​the spray hole, Q represents the amount of oil sprayed, F represents the vibration frequency, M represents the amplitude, and P represents the valve opening pressure;

[0021] Step 4: Based on the range of the aging discrimination factor ρ in step 3, the performance of the host injector is evaluated. When , it indicates that the injector is in good operating condition and can effectively meet its design performance requirements, ensuring the normal operation of the main engine and efficient fuel injection; when When ρ∈(π,+∞], it indicates that the injector is beginning to age, which may affect the injection quality and combustion efficiency of the fuel. At this stage, it is recommended to immediately carry out corresponding maintenance and overhaul to prevent the problem from further deteriorating. In particular, the seals, gaskets, springs or nozzles should be checked and replaced to ensure that the injector can be restored to a more ideal working state. When ρ∈(π,+∞], it indicates that the injector is seriously aged and there is a potential risk of failure, which can greatly reduce the efficiency of the power system and even cause safety hazards. In this case, decisive measures should be taken immediately, including replacing relevant core parts or replacing the entire set to ensure the reliability and safety of the ship's main engine.

[0022] Step 5. Set different injection quantities Q, vibration frequencies F and amplitudes M according to the main engine type, speed and load conditions. Repeat steps 1 to 4 to evaluate the working performance and aging of the main engine injector under different working conditions and vibration conditions, and provide a scientific basis for the maintenance and optimization of the injector. This will help extend the service life of the equipment, improve the operating efficiency and safety of the main engine, and ensure its stable performance under complex navigation conditions.

[0023] The beneficial effects of the present invention are:

[0024] (1) By introducing the performance aging discrimination factor, the working status of the injector can be accurately evaluated, its aging degree can be identified, and a scientific basis can be provided for subsequent maintenance.

[0025] (2) By systematically evaluating the injector performance under different vibration conditions, the maintenance strategy can be optimized, effectively extending its service life, reducing unnecessary maintenance costs, and improving equipment utilization efficiency.

[0026] (3) The method of the present invention is applicable to various types of ship main engines and different operating conditions, has wide applicability and flexibility, and can meet the diverse needs of the ship industry for injector performance evaluation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a system schematic diagram of the present invention; DETAILED DESCRIPTION

[0028] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings:

[0029] First, if Figure 1 As shown, a test bench for evaluating the working performance of a ship main engine injector taking into account different vibration conditions is constructed, and the test bench comprises: a vibration controller (1), a camera (2), filter paper (3), a test box (4), an injector to be evaluated (6), an electromagnetic exciter in the right X-axis direction (7), an injector mounting bracket (8), an electromagnetic exciter in the upper Z-axis direction (9), a ventilation pipe (10), an explosion-proof ventilator (11), a high-pressure hose (12), an adjustable quantitative injection pump (13), an oil suction pipe (14), an oil tank (15), a filter (16), an electromagnetic exciter in the rear Y-axis direction (17), an explosion-proof shadowless lamp (18), and a control station (19);

[0030] The injector (6) to be evaluated is fastened to a mounting bracket (8), and the mounting bracket 8 is suspended in the experimental box (4) and fixed by connecting push rods of (3) electromagnetic exciters, and the (3) electromagnetic exciters are respectively an electromagnetic exciter (7) in the right X-axis direction, an electromagnetic exciter (17) in the rear Y-axis direction, and an electromagnetic exciter (9) in the upper Z-axis direction, which are correspondingly mounted on the right side plate, the rear side plate, and the top plate inside the test box (4). The bottom plate of the test box (4) is made of transparent material and the front cover plate can be opened. Filter paper is laid on the transparent bottom plate. When the injector sprays oil, the atomized oil droplets sprayed from each spray hole on the nozzle will form a spray oil mark (5) corresponding to a single spray hole on the filter paper;

[0031] The suction port of the adjustable quantitative fuel injection pump (13) is connected to the filter (16) through an oil suction pipe (14), and the filter (16) is completely immersed in the oil in the fuel tank. The discharge port of the adjustable quantitative fuel injection pump (13) is connected to the injector (6) to be evaluated through a high-pressure hose (12), and is also connected to the control station (19) through a signal cable. The adjustable quantitative fuel injection pump (13) has two working modes, manual and automatic, and the default working mode is automatic. In this mode, the adjustable quantitative fuel injection pump (13) can receive instructions from the control station (19), automatically inhale and inject oil according to the set injection amount, and return injection parameters such as valve opening pressure;

[0032] The vibration controller (1) is connected to the right side X-axis electromagnetic exciter (7), the rear side Y-axis electromagnetic exciter (17), the upper side Z-axis electromagnetic exciter (9) and the control station (19) through signal cables, receives vibration parameter setting instructions such as frequency and amplitude from the control station, and applies spatial vibration in the X-axis, Y-axis and Z-axis directions to the injector (6) to be evaluated through the above (3) electromagnetic exciters;

[0033] The explosion-proof shadowless lamp (18) is connected to the camera (2) via a cable. The camera (2) is arranged below the transparent bottom plate of the test box (4) and is connected to the control station (19) via a signal cable. With the lighting assistance of the shadowless lamp (18), the camera (2) calibrated with camera parameters can take a picture of the filter paper (3) laid on the transparent bottom plate and transmit it to the control station (19). After image recognition, the parameters such as the spray oil trace area corresponding to each nozzle hole on the filter paper are automatically calculated. During the photographing process, the brightness of the explosion-proof shadowless lamp (18) can be automatically adjusted as needed.

[0034] The ventilation pipe (10) is connected to the opening at the top of the test box (4), and an explosion-proof fan (11) is installed inside the ventilation pipe (10). The explosion-proof fan (11) is connected to the control station (19) through a signal cable. After each spraying experiment, the control station (19) sends a start command to the explosion-proof fan (11) to perform a 15-second air purge to eliminate residual oil mist in the test box (4);

[0035] The control station (19) is connected to the vibration controller (1), the camera (2), the explosion-proof ventilator (11), and the adjustable quantitative injection pump (13) through a signal cable, and controls and coordinates the entire experimental platform by exchanging instructions and data with the above-mentioned devices;

[0036] Next, the job performance evaluation includes the following steps:

[0037] The first step is to simulate the working environment of the ship main engine injector under vibration conditions. The specific steps are as follows: fix the injector to be evaluated (6) on the mounting bracket (8) in the test box (4), connect the injector to be evaluated (6) and the adjustable quantitative injection pump 13) with a high-pressure hose (12), then lay the filter paper (3) on the transparent bottom plate in the test box (4) and make the center of the filter paper directly below the nozzle, then set the injection amount Q, vibration frequency F and amplitude M on the control station (19), and the control station (19) communicates with the vibration controller (1) and the adjustable quantitative injection pump (13) through a signal cable, so that the vibration controller (1) drives (3) electromagnetic exciters to work so as to apply spatial vibration in the X-axis, Y-axis and Z-axis directions, so that the adjustable quantitative injection pump (13) automatically vents, accumulates pressure, executes injection instructions and returns the valve opening pressure P;

[0038] The second step is to test the spray atomization parameters of the host fuel injector under vibration conditions. The specific steps are as follows: the control station (19) communicates with the camera (2) and the explosion-proof ventilator (11) through a signal cable, so that the explosion-proof shadowless lamp (18) gives a peak brightness during the spray atomization period, and the camera (2) takes a picture and transmits it back. The control station (19) calculates the oil trace area corresponding to each fuel injection hole by using the camera calibration parameters and image recognition technology, and finally obtains the oil trace areas A1, A2, ..., A corresponding to all λ fuel injection holes of the fuel injector to be evaluated under the conditions of fuel injection amount Q, vibration frequency F, amplitude M and valve opening pressure P. λ , and finally control the explosion-proof ventilator (11) to start sweeping air and trigger a (15) second delay timer;

[0039] The third step is to calculate the performance aging factor ρ of the ship main engine injector under vibration conditions by the following formula:

[0040]

[0041] Where λ is the total number of injection holes of the injector, A max =max(A1, A2, ..., A λ ) represents the maximum value of the oil trace area of ​​the nozzle hole, A min =min(A1, A2, ..., A λ ) represents the minimum value of the oil trace area of ​​the nozzle hole, A sum =sum(A1, A2, ..., A λ ) represents the sum of the oil trace areas of all nozzle holes, A avg =avg(A1, A2, ..., A λ ) represents the average value of the oil mark area of ​​the nozzle hole, represents the standard deviation of the oil trace area of ​​the spray hole, Q represents the amount of oil sprayed, F represents the vibration frequency, M represents the amplitude, and P represents the valve opening pressure;

[0042] Step 4: Based on the range of the aging discrimination factor ρ in step 3, the performance of the host injector is evaluated. When , it indicates that the injector is in good operating condition and can effectively meet its design performance requirements, ensuring the normal operation of the main engine and efficient fuel injection; when When ρ∈(π,+∞], it indicates that the injector is beginning to age, which may affect the injection quality and combustion efficiency of the fuel. At this stage, it is recommended to immediately carry out corresponding maintenance and overhaul to prevent the problem from further deteriorating. In particular, the seals, gaskets, springs or nozzles should be checked and replaced to ensure that the injector can be restored to a more ideal working state. When ρ∈(π,+∞], it indicates that the injector is seriously aged and there is a potential risk of failure, which can greatly reduce the efficiency of the power system and even cause safety hazards. In this case, decisive measures should be taken immediately, including replacing relevant core parts or replacing the entire set to ensure the reliability and safety of the ship's main engine.

[0043] Step 5. Set different injection quantities Q, vibration frequencies F and amplitudes M according to the main engine type, speed and load conditions. Repeat steps 1 to 4 to evaluate the working performance and aging of the main engine injector under different working conditions and vibration conditions, and provide a scientific basis for the maintenance and optimization of the injector. This will help extend the service life of the equipment, improve the operating efficiency and safety of the main engine, and ensure its stable performance under complex navigation conditions.

Claims

1. The control station (19) is connected to the vibration controller (1), the camera (2), the explosion-proof ventilator (11), and the adjustable quantitative fuel injection pump (13) through signal cables, and controls and coordinates the entire experimental platform by exchanging instructions and data with the above-mentioned devices; Job performance evaluation includes the following steps: The first step is to simulate the working environment of the ship main engine injector under vibration conditions. The specific steps are as follows: fix the injector to be evaluated (6) on the mounting bracket (8) in the test box (4), connect the injector to be evaluated (6) and the adjustable quantitative injection pump (13) with a high-pressure hose (12), then lay the filter paper (3) on the transparent bottom plate in the test box (4) and make the center of the filter paper directly below the nozzle, then set the injection amount Q, vibration frequency F and amplitude M on the control station (19), and the control station (19) communicates with the vibration controller (1) and the adjustable quantitative injection pump (13) through a signal cable, so that the vibration controller (1) drives (3) electromagnetic exciters to work so as to apply spatial vibration in the X-axis, Y-axis and Z-axis directions, so that the adjustable quantitative injection pump (13) automatically vents, accumulates pressure, executes injection instructions and returns the valve opening pressure P; The second step is to test the spray atomization parameters of the host fuel injector under vibration conditions. The specific steps are as follows: the control station (19) communicates with the camera (2) and the explosion-proof ventilator (11) through a signal cable, so that the explosion-proof shadowless lamp (18) gives a peak brightness during the spray atomization period, and the camera (2) takes a picture and transmits it back. The control station (19) calculates the oil trace area corresponding to each fuel injection hole by using the camera calibration parameters and image recognition technology, and finally obtains the oil trace areas A1, A2, ..., A corresponding to all λ fuel injection holes of the fuel injector to be evaluated under the conditions of fuel injection amount Q, vibration frequency F, amplitude M and valve opening pressure P. λ , and finally control the explosion-proof ventilator (11) to start sweeping air and trigger a (15) second delay timer; The third step is to calculate the performance aging factor ρ of the ship main engine injector under vibration conditions by the following formula: Where λ is the total number of injection holes of the injector, A max =max(A1,A2,…,A λ ) represents the maximum value of the oil trace area of ​​the nozzle hole, A min =min(A1,A2,…,A λ ) represents the minimum value of the oil trace area of ​​the nozzle hole, A sum =sum(A1,A2,…,A λ ) represents the sum of the oil trace areas of all nozzle holes, A avg =avg(A1,A2,…,A λ ) represents the average value of the oil mark area of ​​the nozzle hole, represents the standard deviation of the oil trace area of ​​the spray hole, Q represents the amount of oil sprayed, F represents the vibration frequency, M represents the amplitude, and P represents the valve opening pressure; Step 4: Based on the range of the aging discrimination factor ρ in step 3, the performance of the host injector is evaluated. When the fuel injector is in good condition, it can effectively meet its design performance requirements, ensure the normal operation of the main engine and the efficient injection of fuel; when When ρ∈(π,+∞], it indicates that the injector is beginning to age, which may affect the injection quality and combustion efficiency of the fuel. At this stage, it is recommended to immediately carry out corresponding maintenance and overhaul to prevent the problem from further deteriorating. In particular, the seals, gaskets, springs or nozzles should be checked and replaced to ensure that the injector can be restored to a more ideal working state. When ρ∈(π,+∞], it indicates that the injector is seriously aged and there is a potential risk of failure, which can greatly reduce the efficiency of the power system and even cause safety hazards. In this case, decisive measures should be taken immediately, including replacing relevant core parts or replacing the entire set to ensure the reliability and safety of the ship's main engine. Step 5. Set different injection quantities Q, vibration frequencies F and amplitudes M according to the main engine type, speed and load conditions. Repeat steps 1 to 4 to evaluate the working performance and aging of the main engine injector under different working conditions and vibration conditions, and provide a scientific basis for the maintenance and optimization of the injector. This will help extend the service life of the equipment, improve the operating efficiency and safety of the main engine, and ensure its stable performance under complex navigation conditions.

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