Risk test evaluation method for ship deck fuel oil working environment

Abstract

The invention discloses a risk test evaluation method for a ship deck fuel oil operation environment. The risk test evaluation method comprises the following steps: building a first type of test facility according to the ship deck fuel oil operation environment; carrying out multi-stage tests on fuel oil steam ignition of the fuel oil under different radiation conditions, different radiation time and different test temperatures on the first type of test facilities to obtain a first type of test results; improving the first type of test facility to obtain a second type of test facility; starting a radiation test according to preset frequency and power after the test temperature in the second type of test facility is controlled to the highest temperature of the first type of test result to obtain a second type of test result; according to the first type of test results and the second type of test results, risk assessment is conducted on the ship deck fuel oil working environment, and assessment results are obtained. According to the method, the risk of the ship deck fuel oil operation environment can be comprehensively evaluated, the evaluation accuracy is improved, and a scientific basis is provided for formulating corresponding safety measures and operation regulations.

Description

Technical Field

[0001] The invention belongs to the technical field of fuel oil operation safety, and in particular relates to a hazard test assessment method for a fuel oil operation environment on a ship deck. Background Art

[0002] Surface ships carrying aircraft need to carry out a large number of aircraft refueling and unloading operations. At the same time, the electromagnetic radiation field generated by the ship's radar, communication and other high-power equipment in the refueling operation area, when the energy is large enough, may induce enough energy in the metal structure to form arcs or sparks. When the mixing ratio of fuel vapor and air is appropriate and the ambient temperature is suitable, there is a certain probability that the arcs or sparks formed by the radio frequency field will ignite, causing fires, explosions and other serious consequences. At present, the domestic standards GJB1389A-2005 (system electromagnetic compatibility requirements), GJB1446.40-1992 (ship system interface requirements electromagnetic environment) and HJB34A-2007 (ship electromagnetic compatibility specifications) give relevant qualitative requirements for electromagnetic environment hazards and protection of fuel. Only the US Navy Technical Manual (NAVSEA OP 3565) gives safety limits for electromagnetic environment hazards to motor gasoline and aviation gasoline (the power density limit for frequencies less than 225MHz is 0.009mW / cm2, and the power density limit for frequencies greater than 225MHz is 5W / cm2). No safety limits for electromagnetic environment hazards to high-flashpoint fuels are given.

[0003] In view of the fact that the current domestic standards related to the hazards of electromagnetic radiation to fuel are not perfect in terms of quantitative electromagnetic environment restrictions or distance restrictions, and the two power amplitude limits proposed by the US Navy Technical Manual NAVSEA OP 3565 "Electromagnetic Radiation Hazards" with 225MHz as the dividing line have large fluctuations and lack sufficient test data support. Therefore, it is necessary to carry out electromagnetic safety test research on fuel operations on the deck of surface ships to examine the impact of electromagnetic radiation from high-power equipment on the safety of aviation kerosene. In the absence of relevant standards and specifications for such test methods in China, the present invention proposes a dangerous test assessment method for the fuel operation environment on the deck of a ship, constructs direct irradiation of a strong electromagnetic environment on the deck, and uses an extreme simulation device to assess the electromagnetic safety of fuel operations, providing support for the detailed design of the operating procedures for subsequent surface ship deck loading and unloading operations. Summary of the invention

[0004] In view of this, the present invention proposes a method for evaluating the hazard test of the fuel oil operation environment on a ship deck, which can more comprehensively evaluate the hazard of the fuel oil operation environment on a ship deck. This method not only improves the accuracy of the evaluation, but also provides a scientific basis for formulating corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of fuel oil operations on ship decks.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for evaluating the hazard of a fuel oil operation environment on a ship deck, comprising:

[0007] According to the actual ship deck fuel operation environment, the first type of test facility for simulating refueling equipment with metal fuel containers as the main feature was built;

[0008] Based on the controlled variable test method, multi-stage tests of fuel vapor ignition under different radiation conditions, different radiation times and fuel at different test temperatures were carried out on the first type test facility to obtain the first type test results;

[0009] The first type of test facility is improved by replacing the metal fuel container with a wave-transparent fuel container, and arranging two discharge electrodes with opposite tips above the wave-transparent fuel container to obtain a second type of test facility;

[0010] Determine the maximum test temperature based on the first type test results, control the test temperature in the second type test facility to the maximum test temperature, and then start the radiation test according to the preset frequency and power to obtain the second type test results;

[0011] Based on the first and second test results, a hazard assessment of the fuel operating environment on the ship deck was conducted and the assessment results were obtained.

[0012] Preferably, the first type of test facility includes a test device and a test device, wherein:

[0013] The equipment under test includes the test fuel, metal fuel container and fuel nozzle. The test fuel is a test fuel that meets the requirements of relevant standards and specifications, and its type and model are consistent with the fuel actually used in the ship deck fuel operation system;

[0014] The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment, wherein the electromagnetic environment construction equipment includes a signal source, a radio frequency power amplifier, a radiation antenna, a field strength monitor, an oil and gas concentration tester, a temperature sensor, a wind speed and direction sensor, and a heating plate;

[0015] The test data acquisition equipment includes a camera and an oil and gas concentration tester.

[0016] Preferably, based on the controlled variable test method, the first type of test facility is subjected to multi-stage tests of fuel vapor ignition under different radiation conditions, different radiation times, and fuel at different test temperatures, and the first type of test results include:

[0017] Step S101, heating the fuel until it reaches a specified temperature, testing and recording the oil and gas concentration at the fuel container port, and turning on the radiation system;

[0018] Step S102, irradiating the simulated refueling device test facility, testing and recording the fuel vapor ignition condition and the fuel vapor concentration;

[0019] Step S103, changing the radiation source working condition and continuing the test;

[0020] Step S104, judging whether the test of different radiation source working conditions is completed, if not completed, returning to step S102, if completed, proceeding to the next step;

[0021] Step S105, changing the radiation time length and continuing the test;

[0022] Step S106, judging whether the test of different radiation time lengths is completed, if not completed, returning to step S102, if completed, proceeding to the next step;

[0023] Step S107, changing the test temperature and continuing the test;

[0024] Step S108, determining whether the tests at different test temperatures are completed, if not completed, returning to step S101, if completed, generating the first type of test results based on the collected data.

[0025] Preferably, a hazard assessment of the fuel oil operation environment on the ship deck is performed based on the first type test results and the second type test results, and the assessment results include:

[0026] Based on the results of the first and second types of tests, the fuel vapor ignition conditions under different radiation conditions, different radiation times and fuel at different test temperatures are determined, and multiple ignition critical points x are extracted. i Radiation conditions (F i ,P i ), radiation time T i And the test temperature C i , where x i =[(F i ,P i ),T i ,C i ],i=1,2,…,N,F i Indicates the radiation frequency, P i represents the radiation power, N represents the total number of critical ignition points;

[0027] Based on the relevant data of multiple ignition critical points, a scattered data representation in four-dimensional data space is constructed, and a scattered data model is obtained by using radial basis functions to perform data interpolation and smoothing of the ignition critical points in four-dimensional data space.

[0028] Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is divided into two states: ignition and non-ignition test data range in the scatter data model, thus obtaining a relatively simple evaluation model.

[0029] Obtain a set of historical environmental data of the ship deck fuel operation environment in the actual working process, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model;

[0030] When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state;

[0031] All dangerous states recorded in any preset period and their corresponding shortest distances are counted, and based on the corresponding relationship between the preset distance and the weight, the hazard assessment of the deck fuel operation environment is performed by weighted summation to obtain the assessment result.

[0032] Preferably, using radial basis function to perform data interpolation and smoothing of the ignition critical point in four-dimensional data space to obtain a scattered data model includes:

[0033] Choose a radial basis function based on a Gaussian function:

[0034]

[0035] Among them, φ(·) represents the Gaussian function, r represents the Euclidean distance from the point to the origin, e represents the natural logarithm, and α represents the shape parameter;

[0036] For the scattered data representation in four-dimensional data space, construct an interpolation function:

[0037]

[0038] Where S(·) represents the interpolation function, c i is the i-th coefficient, c is the coefficient vector of a linear term, and x is the point to be interpolated;

[0039] For the critical point of ignition x i , determine its observed value f(x i ), construct the following linear system:

[0040]

[0041] Solve the linear system using numerical methods to determine the coefficient c i and coefficient vector c;

[0042] Based on the interpolation function, the data at any point in the four-dimensional data space is interpolated and smoothed to obtain a scattered data model.

[0043] The present invention has achieved at least the following beneficial effects:

[0044] 1. Through the present invention, the danger of the fuel oil operation environment on the ship deck can be more comprehensively evaluated. This method not only improves the accuracy of the evaluation, but also provides a scientific basis for formulating corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of fuel oil operations on the ship deck.

[0045] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art may be taught from the practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration:

[0047] Figure 1 This is a flowchart of the overall steps of a method for evaluating the hazard test of a fuel oil operation environment on a ship deck according to an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of the layout of the first type of test facilities in an embodiment of the present invention;

[0049] Figure 3 This is a schematic diagram of the layout of the second type of test facilities in an embodiment of the present invention;

[0050] Figure 4 It is a flowchart of the test steps in the embodiment of the present invention. DETAILED DESCRIPTION

[0051] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0052] The present invention provides a method for evaluating the hazard of a fuel oil operation environment on a ship deck, referring to Figure 1 , in view of the radiation of high-power equipment such as radar and communication equipment on surface ships, the safety of fuel operations such as fuel loading and unloading on the ship deck was tested and evaluated, including:

[0053] According to the actual ship deck fuel operation environment, the first type of test facility for simulating refueling equipment with metal fuel containers as the main feature was built;

[0054] Based on the controlled variable test method, multi-stage tests of fuel vapor ignition under different radiation conditions, different radiation times and fuel at different test temperatures were carried out on the first type test facility to obtain the first type test results;

[0055] The first type of test facility is improved by replacing the metal fuel container with a wave-transparent fuel container, and arranging two discharge electrodes with opposite tips above the wave-transparent fuel container to obtain a second type of test facility;

[0056] Determine the maximum test temperature based on the first type test results, control the test temperature in the second type test facility to the maximum test temperature, and then start the radiation test according to the preset frequency and power to obtain the second type test results;

[0057] Based on the first and second test results, a hazard assessment of the fuel operating environment on the ship deck was conducted and the assessment results were obtained.

[0058] The working principle and beneficial effects of the above technical solution are as follows: by building a first type of test facility simulating a refueling device, the present invention can simulate the actual ship deck fuel oil operation environment and conduct accurate test evaluation. This simulation test method improves the accuracy and reliability of the safety assessment of ship deck fuel oil operation. The first type of test facility is tested at multiple levels using a controlled variable test method, including different radiation conditions, time and temperature conditions. The present invention can systematically study the influence of various factors on fuel oil vapor ignition. This method enhances the control ability of the test conditions and increases the diversity of the test. The first type of test facility is improved, and the second type of test facility with a wave-transparent fuel oil container and a discharge electrode is introduced. The present invention can more realistically simulate the actual environment of the ship deck. This improved test facility not only improves the practicality of the test, but also allows a more accurate study of the influence of electromagnetic radiation on fuel oil vapor ignition, thereby providing more accurate data support for the risk assessment of the ship deck fuel oil operation environment. The present invention can more comprehensively assess the risk of the ship deck fuel oil operation environment by improving the test facility and controlling the test conditions. This method not only improves the accuracy of the assessment, but also provides a scientific basis for formulating corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of ship deck fuel operations.

[0059] In a specific embodiment, the present invention provides a test environment, a test site, a test device, a test equipment, a test arrangement, pre-test preparations, test steps, test result evaluation, etc., as follows:

[0060] 1. Test environment

[0061] The test should be carried out under normal atmospheric conditions, with clear weather without rain or snow and wind force less than level 3-4. The ambient temperature, humidity and atmospheric pressure during the test should not exceed the allowable tolerance range of the test instrument and the test piece during normal operation.

[0062] 2. Test site

[0063] The test site should be selected based on the needs of the test project and specific site conditions, such as open test sites, on-site test sites, etc. The selection of the test site should meet the following requirements:

[0064] a) The test area should be large enough to ensure that the distance between electromagnetic radiation and the test piece and adjacent structures and other objects is not less than 1.5 times the radiation distance to prevent the proximity effect from adversely affecting the test results, adjacent structures and other objects;

[0065] b) The test site should have necessary warning, isolation and other safety measures to prevent high field strength from causing harm to personnel;

[0066] c) Good grounding and isolation protection measures should be in place to prevent the rise in ground potential caused by high field strength from affecting the equipment and test pieces on site.

[0067] d) Provide power, hydraulic, ventilation, fire protection, safety and other necessary support or guarantee equipment and facilities required for the normal operation of SUT / EUT and test equipment.

[0068] 3. Test equipment

[0069] The equipment under test includes: the tested fuel, fuel container, fuel gun simulation device and copper discharge electrode, which shall meet the following requirements:

[0070] a) The fuel to be tested should be a test fuel that complies with the requirements of relevant standards and specifications, and its type and model should be consistent with the fuel actually used in the system.

[0071] b) The fuel container should be configured in two types: wave-transparent and metal, to simulate a small amount of fuel leakage in the system and the fuel storage state respectively; the capacity should be no less than 4L; the bottom should be flat and fully in contact with the heating plate.

[0072] c) The electromagnetic properties of the material of the fueling gun simulation device and the actual fueling connector are consistent.

[0073] d) The number of copper discharge electrodes is not less than two, with a diameter of 5mm to 8mm and a length of 30mm to 90mm

[0074] The test fuel, metal fuel container and refueling gun simulation device in the test equipment together constitute a simulated refueling operation test facility; the wave-transparent fuel container and copper discharge electrode together constitute a metal discharge electrode test facility.

[0075] 4. Test equipment

[0076] The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment.

[0077] (1) Electromagnetic environment construction equipment

[0078] The test equipment includes: signal source, RF power amplifier, radiation antenna, field strength monitor, oil and gas concentration tester, temperature sensor, wind speed and direction sensor, and heating plate. The basic requirements of the test equipment are as follows:

[0079] a) Field intensity monitors, oil and gas concentration testers, temperature sensors, and wind speed and direction sensors should have sufficient dynamic range;

[0080] b) The heating plate should have a flat heating surface structure with controllable temperature rise, used to place and heat the fuel container;

[0081] c) The camera should have a continuous recording function and sufficient clarity to capture the intermittent discharge sparking effect;

[0082] d) The signal source should be able to cover the required frequency range and be modulated with pulses of a specified duty cycle, or have a modulation method specified in the test outline;

[0083] e) The signal source, RF power amplifier and antenna should be able to generate the required field strength level in the test area, and its harmonics should be as small as possible. The field strength at each harmonic frequency should be at least 6 dB lower than the fundamental wave field strength;

[0084] f) Priority should be given to using high-power radiation source equipment or prototypes with system configuration to replace signal sources, RF power amplifiers and antennas to generate the required field strength level in the test area.

[0085] (2) Test data acquisition equipment

[0086] The test sampling equipment mainly includes cameras and oil and gas concentration testers.

[0087] The main technical indicators of the camera are as follows:

[0088] a) Lens magnification: not less than 4 times;

[0089] b) Pixels: no less than 4 million;

[0090] c) Picture output clarity: no less than 2560*1440@30fps;

[0091] d)Support night mode.

[0092] The main technical indicators of the oil and gas concentration tester are as follows:

[0093] a) Sampling method: pump suction;

[0094] b) Anti-electromagnetic radiation EMI / RF level: EMC Directive 2004 / 108 / EEC;

[0095] c) Detection range 10.6eV: 0.1ppm~15,000ppm;

[0096] d) Resolution: 0.1ppm;

[0097] e)Response time: (T90) 2s.

[0098] 5. Experimental arrangement

[0099] During the measurement, arrange the radiation system and the equipment under test according to the test requirements, place the fuel container on the electric heating plate, place the camera near the fuel container, with the viewing angle facing the fuel container and the opening above it; fix the oil and gas concentration tester at the opening above the fuel container; place the field strength monitor near the fuel container; refer to the attached test equipment layout. Figure 2 .

[0100] After completing the test on the impact of electromagnetic radiation on fuel vapor concentration and safety, replace the simulated refueling test facility with a copper discharge electrode, place the camera near the fuel container, with the viewing angle facing the fuel container and the opening above it; place the field strength monitor near the fuel container; refer to the attached test equipment layout. Figure 3 .

[0101] The camera, oil and gas concentration tester and field strength monitor should be arranged in a way that avoids shielding the radiation system from the simulated refueling device test facilities and copper discharge electrodes.

[0102] 6. Preparation before the test

[0103] Before the formal test, the frequency, transmission power, antenna gain, duty cycle and other parameters of the high-power radiation source configured in the system are analyzed; and combined with the actual use of the system, the radiation field strength generated in the specified area is predicted through simulation or pre-testing methods to determine the test conditions and formulate a detailed test plan, including the following:

[0104] a) Determine the key data that needs to be detected and monitored and the location of the data acquisition system;

[0105] b) For different radiation sources, determine the maximum electromagnetic radiation level that the equipment under test may be exposed to, and calculate the value after the radiation level is further increased by 6dB, and determine the amplitude, frequency and other parameters of the radiation field strength used in the test;

[0106] c) Analyze the radiation source’s layout, transmission power, beam pointing and other parameter settings based on the test radiation field strength parameters; calibrate the radiation source to confirm that it is working properly; and confirm the type and performance requirements of the data acquisition system, as well as the radiation protection measures that should be taken by the data acquisition system;

[0107] d) Select room temperature, fuel closed cup flash point temperature, system normal operating upper limit temperature, etc. as the test temperature for the test; if there is no special requirement, the room temperature is set at 25°C, the system normal operating upper limit temperature is set at 65°C, and the flash point temperature is the lowest temperature at which the test fuel vapor flashes.

[0108] e) Determine the verification criteria and result evaluation criteria;

[0109] f) Evaluate existing analytical data and test data from previous tests and incorporate them into test plans and predictive analyses to expand or reduce the scope of the test.

[0110] 7. Test steps (refer to Figure 3 )

[0111] The test steps are as follows:

[0112] a) Place no less than 4L of fuel into a metal fuel container for testing, heat it with an electric heating plate, and measure the temperature with an infrared thermometer.

[0113] b) Start heating, and when the temperature reaches the test temperature "normal temperature", turn on the oil and gas concentration tester and record the oil and gas concentration.

[0114] c) Fix the test temperature, turn on the radiation system, set the frequency, power, beam pointing, etc. as specified in the test outline, start radiation, test and record the fuel vapor ignition condition and fuel vapor concentration;

[0115] d) Fix the test fuel temperature and radiation time, change the radiation source working conditions (change the radiation source frequency, power and other working conditions according to the test outline), and repeat the test according to steps b) and c);

[0116] e) Fix the test temperature and radiation intensity, change the radiation time (irradiation for 30 seconds, 1 minute, and 3 minutes respectively), and repeat the test according to steps b) and c);

[0117] f) Change the test temperature (flash point temperature, upper limit temperature of normal operation of the system), and repeat the test according to step b), step c), step d) and step e);

[0118] g) If no fuel ignition occurs in the above tests, replace the metal fuel container with a transparent wave-transmitting fuel container, and place two copper discharge electrodes with their tips facing each other and a distance of 1 mm above it. The test temperature is set to the highest temperature in the above test steps, turn on the radiation system, set the frequency and power specified in the test outline, start radiation, and test and record the discharge at the electrode tip and the ignition of fuel vapor;

[0119] h) During the test, the electromagnetic radiation field strength near the fuel container is continuously monitored and recorded, and meteorological elements, including temperature, humidity, wind speed and wind direction, are monitored and recorded in real time.

[0120] 8. Evaluation of test results

[0121] If no discharge arc or fuel vapor ignition occurs during the test, the electromagnetic radiation and fuel safety test assessment has been passed.

[0122] The working principle and beneficial effects of the above technical scheme are as follows: the present invention proposes a test method for the hazard of electromagnetic radiation from surface ships to fuel operations on deck, which utilizes a system high-power radiation source equipment / prototype or an equivalent radiation source composed of a signal source, a radio frequency power amplifier and an antenna to form a simulated electromagnetic environment, designs two fuel containers with heaters, refueling guns, copper electrodes and the like to simulate the extreme conditions in oil loading and unloading operations, and accurately analyzes the safety of fuel operations by detecting the ignition of fuel vapor and the oil and gas concentration, which can effectively evaluate the harmful effects of strong electromagnetic radiation on deck fuel operations, and provide support for the detailed design of operating procedures for subsequent surface ship oil loading and unloading operations.

[0123] In a preferred embodiment, a hazard assessment is performed on the fuel oil operation environment on the ship deck according to the first type test results and the second type test results, and the assessment results include:

[0124] Based on the results of the first and second types of tests, the fuel vapor ignition conditions under different radiation conditions, different radiation times and fuel at different test temperatures are determined, and multiple ignition critical points x are extracted. i Radiation conditions (F i ,P i ), radiation time T i And the test temperature C i , where x i =[(F i ,P i ),T i ,C i ],i=1,2,…,N,F i Indicates the radiation frequency, P i represents the radiation power, N represents the total number of critical ignition points;

[0125] Based on the relevant data of multiple ignition critical points, a scattered data representation in four-dimensional data space is constructed, and a scattered data model is obtained by using radial basis functions to perform data interpolation and smoothing of the ignition critical points in four-dimensional data space.

[0126] Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is divided into two states: ignition and non-ignition test data range in the scatter data model, thus obtaining a relatively simple evaluation model.

[0127] Obtain a set of historical environmental data of the ship deck fuel operation environment in the actual working process, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model;

[0128] When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state;

[0129] All dangerous states recorded in any preset period and their corresponding shortest distances are counted, and based on the corresponding relationship between the preset distance and the weight, the hazard assessment of the deck fuel operation environment is performed by weighted summation to obtain the assessment result.

[0130] The working principle and beneficial effects of the above technical solution are as follows: by analyzing the first and second test results, the present invention can determine the fuel vapor ignition conditions under different radiation conditions, time and test temperatures, and extract multiple ignition critical points. This precise analysis helps to deeply understand the ignition characteristics of fuel vapor and provide accurate data support for subsequent hazard assessment. By using radial basis functions to interpolate and smooth the scattered data in four-dimensional data space, the present invention can construct a comprehensive scattered data model. This model can not only reflect the complexity of fuel vapor ignition, but also provide a reliable mathematical basis for hazard assessment. By performing binary segmentation on the scattered data model, the present invention can create a simple judgment model for distinguishing between the state of fuel ignition and the state of non-ignition. Combined with the historical environmental data set, the present invention can accurately assess the risk of fuel operations, and can also calculate the distance between the boundary of the judgment model in real time, and record the dangerous state when the distance is less than the preset threshold. This real-time monitoring and evaluation method can timely identify potential safety risks and provide effective decision support for the safety management of the fuel operation environment on the ship deck. The present invention provides an efficient and accurate method for assessing the hazard of fuel oil operation environment on ship decks by combining test data, four-dimensional data space analysis and real-time monitoring technology. This method not only improves the accuracy and efficiency of the assessment, but also enhances the ability to prevent and respond to potential hazards, which is of great significance for ensuring the safety of ships and their personnel.

[0131] In a preferred embodiment, the scattered point data model obtained by using radial basis function to perform data interpolation and smoothing of the ignition critical point in four-dimensional data space includes:

[0132] Choose a radial basis function based on a Gaussian function:

[0133]

[0134] Among them, φ(·) represents the Gaussian function, r represents the Euclidean distance from the point to the origin, e represents the natural logarithm, and α represents the shape parameter;

[0135] For the scattered data representation in four-dimensional data space, construct an interpolation function:

[0136]

[0137] Where S(·) represents the interpolation function, c i is the i-th coefficient, c is the coefficient vector of a linear term, and x is the point to be interpolated;

[0138] For the critical point of ignition x i , determine its observed value f(x i ), construct the following linear system:

[0139]

[0140] Solve the linear system using numerical methods to determine the coefficient c i and coefficient vector c;

[0141] Based on the interpolation function, the data at any point in the four-dimensional data space is interpolated and smoothed to obtain a scattered data model.

[0142] The working principle and beneficial effects of the above technical solution are as follows: by using the radial basis function based on the Gaussian function to perform data interpolation, the present invention can accurately reconstruct the scattered data model in the four-dimensional data space. This interpolation method can ensure the continuity and smoothness of the data, and provide an accurate data basis for subsequent analysis and evaluation. By constructing and solving the linear system, the present invention can efficiently determine the coefficients and coefficient vectors in the interpolation function. This method not only improves the calculation efficiency, but also ensures the accuracy and reliability of the interpolation result. By using the interpolation function to interpolate and smooth the data at any point in the four-dimensional data space, the present invention can construct a comprehensive scattered data model for evaluating the danger of the fuel oil operation environment on the ship deck. This model can comprehensively consider multiple influencing factors (such as radiation conditions, radiation time, test temperature, etc.), and provide a scientific and systematic analysis tool for danger assessment. The present invention realizes the accurate interpolation and smoothing of scattered data in the four-dimensional data space by combining the radial basis function and the linear system solution. This method not only improves the accuracy of the data model, but also provides an effective technical means for the danger assessment of the fuel oil operation environment on the ship deck, which helps to timely discover and prevent potential safety risks.

[0143] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A method for evaluating the hazard of fuel oil operation environment on a ship deck, characterized in that: include: According to the actual ship deck fuel operation environment, the first type of test facility for simulating refueling equipment with metal fuel containers as the main feature was built; Based on the controlled variable test method, multi-stage tests of fuel vapor ignition under different radiation conditions, different radiation times and fuel at different test temperatures were carried out on the first type test facility to obtain the first type test results; The first type of test facility is improved by replacing the metal fuel container with a wave-transparent fuel container, and arranging two discharge electrodes with opposite tips above the wave-transparent fuel container to obtain a second type of test facility; Determine the maximum test temperature based on the first type test results, control the test temperature in the second type test facility to the maximum test temperature, and then start the radiation test according to the preset frequency and power to obtain the second type test results; Based on the first and second test results, a hazard assessment of the fuel operating environment on the ship deck was conducted and the assessment results were obtained.

2. A method for evaluating the hazard of fuel oil operation environment on a ship deck according to claim 1, characterized in that: The first type of test facilities include the equipment under test and the test equipment, among which: The equipment under test includes the test fuel, metal fuel container and fuel nozzle. The test fuel is a test fuel that meets the requirements of relevant standards and specifications, and its type and model are consistent with the fuel actually used in the ship deck fuel operation system; The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment, wherein the electromagnetic environment construction equipment includes a signal source, a radio frequency power amplifier, a radiation antenna, a field strength monitor, an oil and gas concentration tester, a temperature sensor, a wind speed and direction sensor, and a heating plate; The test data acquisition equipment includes a camera and an oil and gas concentration tester.

3. The method for evaluating the hazard of fuel oil operation environment on a ship deck according to claim 1, characterized in that: Based on the control variable test method, the first type of test facilities are subjected to multi-stage tests of fuel vapor ignition under different radiation conditions, different radiation times, and fuel at different test temperatures, and the first type of test results include: Step S101, heating the fuel until it reaches a specified temperature, testing and recording the oil and gas concentration at the fuel container port, and turning on the radiation system; Step S102, irradiating the simulated refueling device test facility, testing and recording the fuel vapor ignition condition and the fuel vapor concentration; Step S103, changing the radiation source working condition and continuing the test; Step S104, judging whether the test of different radiation source working conditions is completed, if not completed, returning to step S102, if completed, proceeding to the next step; Step S105, changing the radiation time length and continuing the test; Step S106, judging whether the test of different radiation time lengths is completed, if not completed, returning to step S102, if completed, proceeding to the next step; Step S107, changing the test temperature and continuing the test; Step S108, determining whether the tests at different test temperatures are completed, if not completed, returning to step S101, if completed, generating the first type of test results based on the collected data.

4. The method for evaluating the hazard of fuel oil operation environment on a ship deck according to claim 1 is characterized in that: The hazard assessment of the fuel oil operation environment on the ship deck is conducted based on the first type test results and the second type test results, and the assessment results include: Based on the results of the first and second types of tests, the fuel vapor ignition conditions under different radiation conditions, different radiation times and fuel at different test temperatures are determined, and multiple ignition critical points x are extracted. i Radiation conditions (F i , P i ), radiation time T i And the test temperature C i , where x i =[(F i ,P i ), T i ,C i ], i = 1, 2, ..., N, F i Indicates the radiation frequency, P i represents the radiation power, N represents the total number of critical ignition points; Based on the relevant data of multiple ignition critical points, a scattered data representation in four-dimensional data space is constructed, and a scattered data model is obtained by using radial basis functions to perform data interpolation and smoothing of the ignition critical points in four-dimensional data space. Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is divided into two states: ignition and non-ignition test data range in the scatter data model, thus obtaining a relatively simple evaluation model. Obtain a set of historical environmental data of the ship deck fuel operation environment in the actual working process, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model; When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state; All dangerous states recorded in any preset period and their corresponding shortest distances are counted, and based on the corresponding relationship between the preset distance and the weight, the hazard assessment of the deck fuel operation environment is performed by weighted summation to obtain the assessment result.

5. A method for testing and assessing the hazard of a ship deck fuel oil operation environment according to claim 4, characterized in that: The method of using radial basis function to perform data interpolation and smoothing of the ignition critical point in four-dimensional data space to obtain a scattered point data model includes: Choose a radial basis function based on a Gaussian function: Among them, φ(·) represents the Gaussian function, r represents the Euclidean distance from the point to the origin, e represents the natural logarithm, and α represents the shape parameter; For the scattered data representation in four-dimensional data space, construct an interpolation function: Where S(·) represents the interpolation function, c i is the i-th coefficient, c is the coefficient vector of a linear term, and x is the point to be interpolated; For the critical point of ignition x i , determine its observed value f(x i ), construct the following linear system: Solve the linear system using numerical methods to determine the coefficient c i and coefficient vector c; Based on the interpolation function, the data at any point in the four-dimensional data space is interpolated and smoothed to obtain a scattered data model.

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