A method for analyzing and predicting the fire hazard level of ship energy compartments

Abstract

The present invention relates to the field of ship fire emergency disposal technology, and in particular to a method for analyzing and predicting the fire hazard level of a ship energy compartment. The method includes the following steps: establishing a fire hazard level evaluation index set, screening and combining the fire hazard level evaluation indexes generated by experts or evaluation systems, and establishing an evaluation index set; obtaining the hazard level scores of various fire indicators from different evaluation systems; establishing fuzzy grading functions of different hazard levels; establishing an evaluation database, collecting the current evaluation indexes to determine the hazard level or the probability of different hazard levels; the present invention provides a solution for realizing automated and continuous fire hazard level analysis and prediction based on fuzzy classification and index analysis, and continuously tracking and analyzing the fire development process, which can help decision makers effectively obtain the fire status and facilitate them to take necessary emergency disposal plans in a targeted manner.

Description

Technical Field

[0001] The present invention relates to the technical field of emergency disposal of ship fires, and in particular to a method for analyzing and predicting the degree of fire hazard in a ship energy compartment. Background Art

[0002] The ship's energy tank is the basis for the continuous and stable operation of the ship's system. Since a large amount of fuel or flammable materials are stored in the energy tank, once a fire occurs in the energy tank, if it is not promptly and targetedly handled, it will quickly endanger the safety of the entire ship and the operating tasks. However, there is currently no clear plan for emergency disposal methods for different levels and degrees of harm. For fires of different levels, the overall principle is to ensure a safe margin and adopt a rich disposal plan. However, for specific ships such as ocean-going ships and military ships, the resources allocated to emergency disposal (including manpower and material resources) are limited. During the long-term execution of tasks, various resources should be reasonably allocated to reduce the consumption of emergency disposal resources and ensure the safety of the ship for a long time. Summary of the invention

[0003] The purpose of the present invention is to provide a method for analyzing and predicting the fire hazard level of a ship energy compartment based on actual needs, which can use a ship data system to quickly analyze the fire hazard level of a ship, so as to facilitate decision-making and quickly configure emergency response plans of different levels.

[0004] To achieve the above purpose, the present invention adopts the following technical solution.

[0005] A method for analyzing and predicting the fire hazard level of a ship energy compartment comprises the following steps:

[0006] A1. Establish a fire hazard evaluation index set. Based on the fire hazard evaluation indexes generated by experts or evaluation systems, screen and combine them to establish an evaluation index set X containing several evaluation indexes:

[0007] X={x1,x2...x j ...,x J}

[0008] where x j represents the jth evaluation index, and J represents the total number of evaluation indicators;

[0009] A2. Based on event annotation, obtain the danger level scores Q of various fire indicators by different evaluation systems i i,j :

[0010]

[0011] where q i,j represents the scoring weight given by the ith expert or system for the jth evaluation index of a fire, xi,j represents the score given by expert i for indicator j;

[0012] Statistical analysis of all experts or systems' scores on the danger level of various fire indicators Among them, q, ω i is the weight coefficient of the ith expert or system, I is the total number of experts or systems;

[0013] A3. Establish a fire hazard evaluation model

[0014] The danger level of each type of fire is evaluated and divided into at least seven danger levels based on the danger level: extremely dangerous, highly dangerous, relatively dangerous, ordinary dangerous, relatively small dangerous, relatively small dangerous, and extremely small dangerous, and they are marked with F respectively. VH 、F H 、F SH 、F M 、F SL 、F L 、F VL express;

[0015] Where H = High indicates a high risk level, L = Low indicates a low risk level, V indicates an increased risk level, and S indicates a decreased risk level. According to the risk level score set of each type of fire determined in step A2, the actual loss caused by each type of fire is estimated, and trapezoidal fuzzy is used to establish fuzzy grading functions for different risk levels. The trapezoidal fuzzy grading function is as follows:

[0016]

[0017]

[0018] in Represents the normalized fire danger rating;

[0019] f w (r i,j ) represents the risk level score R i,j The fire danger level is F w The probability density function at time t and the order value of the fire danger degree score are obtained by fitting the fire statistical data;

[0020] A4. Establish an evaluation database and determine the danger level or the probability of different danger levels by collecting current evaluation indicators.

[0021] A further improvement or preferred implementation of the above-mentioned ship energy compartment fire hazard analysis and prediction method, in step A1, the evaluation index set includes at least combustion index x1, energy release index x2, scale index x3, and pressure difference index x4;

[0022] Among them, the combustion index

[0023] Energy release index

[0024] Size Index

[0025] Pressure difference index

[0026] m k The average mass burning rate of the kth type of fuel is represented by It refers to the maximum mass burning rate of the kth type of fuel in the energy compartment, C represents the flame attenuation coefficient, α k Refers to the correction factor for the kth type of fuel, D k represents the total mass of the kth type of fuel, K represents the total type of fuel; M k It refers to the combustion heat of the kth type of fuel; ρ is the average air density in the energy cabin, g is the real-time gravity acceleration in the cabin; Δσ is the average pressure difference between the energy cabin and its surrounding cabins, and V is the volume of the energy cabin;

[0027] A further improvement or preferred implementation of the above-mentioned ship energy compartment fire hazard analysis and prediction method, the step A1 also includes an index processing step for dealing with the fire hazard level of a closed ship environment, and the specific steps include adding the following evaluation indicators according to the ship situation:

[0028] Considering the thermal radiation value index of the energy cabin material and the personnel, the evaluation index y1 considering the thermal radiation of the fuel is obtained, and:

[0029]

[0030] L k The heat radiation distance of fuel k that can cause damage to the energy module or personal injury, L' k represents the straight-line distance between the mass center of the fuel k and the energy cabin or the personnel in the cabin, T k It represents the flame temperature when fuel k is burning, and T0 is the flame temperature when the preset reference fuel is burning.

[0031] A further improvement or preferred implementation of the aforementioned ship energy tank fire hazard analysis and prediction method further includes considering the impact of changes in the internal and external pressure and oxygen content of the energy tank, obtaining a fuel-air impact index y2 that considers the impact of fuel on oxygen and pressure, and:

[0032]

[0033] in It represents the air volume change caused by the combustion of unit mass of fuel k.

[0034] Its beneficial effects are:

[0035] The present invention makes full use of the information collection capabilities of various data sensor information collection systems in existing ship energy compartments, and provides a solution based on fuzzy classification and index analysis to realize automated and continuous fire hazard analysis and prediction, and to continuously track and analyze the fire development process. This solution can help decision makers effectively obtain the fire status and facilitate them to take necessary emergency response plans in a targeted manner.

[0036] The present invention is beneficial to reducing the personnel and resource costs of fire emergency response, and on the basis of providing effective fire information, assists decision-makers to better determine the extent of damage that may be caused by the fire, so that the decision-makers can make effective targeted decisions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a flow chart for creating a method for analyzing and predicting the degree of fire hazard in ship energy compartments.

[0038] Figure 2 It is an application flow chart for analyzing the fire hazard level of ship energy compartments. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with specific embodiments.

[0040] The ship energy compartment fire hazard analysis and prediction method of the present invention is mainly used for fire risk prediction of various ships that need to perform long-term offshore operations and various submersible equipment, so as to ensure better endurance when internal emergency disposal resources are limited.

[0041] The basic process of the ship energy compartment fire hazard analysis and prediction method of the present invention is as follows: Figure 1 As shown, it mainly includes the following steps:

[0042] Establishing fire hazard rating levels

[0043] A1. Establish a fire hazard evaluation index set

[0044] Based on the fire hazard evaluation indicators generated by experts or evaluation systems, a combination of evaluation indicators is screened and combined to establish an evaluation indicator set X = {x1, x2...x j ...,x J}, where x jrepresents the jth evaluation index, and J represents the total number of evaluation indexes; wherein the evaluation index set includes at least combustion index x1, energy release index x2, scale index x3, and pressure difference index x4;

[0045] Among them, the combustion index

[0046] Energy release index

[0047] Size Index

[0048] Pressure difference index

[0049] m k The average mass burning rate of the kth type of fuel is represented by It refers to the maximum mass burning rate of the kth type of fuel in the energy compartment, C represents the flame attenuation coefficient, α k Refers to the correction factor for the kth type of fuel, D k represents the total mass of the kth type of fuel, K represents the total type of fuel; M k It refers to the combustion heat of the kth type of fuel; ρ is the average air density in the energy cabin, g is the real-time gravity acceleration in the cabin; Δσ is the average pressure difference between the energy cabin and its surrounding cabins, and V is the volume of the energy cabin;

[0050] In particular, for some Qianhang ships, including but not limited to submersible ships, underwater icebreakers and other specific ships, due to the relatively closed environment and the pressure of seawater inside and outside the hull, the risk of fire danger is affected by more other factors. At this time, the purpose of fire emergency response is to ensure the safety of personnel first. For such ships, the following steps need to be performed:

[0051] Considering the evaluation index of fuel thermal radiation, for some specific fuels or materials, higher thermal radiation values ​​will be generated compared with traditional fuels. In a closed environment, it is necessary to further consider the thermal radiation value index of the energy cabin's own materials and the personnel's tolerance, and obtain the evaluation index y1 considering fuel thermal radiation, and:

[0052]

[0053] L k The heat radiation distance of fuel k that can cause damage to the energy module or personal injury, L' k represents the straight-line distance between the mass center of the fuel k and the energy cabin or the personnel in the cabin, T k represents the flame temperature when fuel k is burning, T0 is the flame temperature when the preset reference fuel is burning;

[0054] Due to the closed environment, the ship's own air regeneration capacity is limited, and the fuel combustion will quickly reduce the oxygen in the cabin and have a direct impact on the pressure and air in the energy cabin. Therefore, it is necessary to consider the impact of changes in the internal and external pressure and oxygen content of the energy cabin, and obtain the fuel air impact index y2 that considers the impact of fuel on oxygen and pressure, and:

[0055]

[0056] in It represents the air volume variable caused by the combustion of unit mass of fuel k;

[0057] L k The heat radiation distance of fuel k that can cause damage to the energy module or personal injury, L' k represents the straight-line distance between the mass center of the fuel k and the energy cabin or the personnel in the cabin, T k It represents the flame temperature when fuel k is burning, and T0 is the flame temperature when the preset reference fuel is burning.

[0058] A2. Based on event annotation, obtain the danger level scores of various fire indicators by different evaluation systems i q i,j represents the scoring weight given by the ith expert or system for the jth evaluation index of a fire, x i,j It represents the score given by expert i for indicator j, and statistically analyzes the dangerousness scores of all experts or systems for various fire indicators. Among them, q, ω i is the weight coefficient of the ith expert or system, I is the total number of experts or systems;

[0059] A3. Establish a fire hazard evaluation model

[0060] The danger level of each type of fire is evaluated and divided into at least seven danger levels based on the danger level: extremely dangerous, highly dangerous, relatively dangerous, ordinary dangerous, relatively small dangerous, relatively small dangerous, and extremely small dangerous, and they are marked with F respectively. VH 、F H 、F SH 、F M 、F SL 、F L 、F VL Indicates, where H = High indicates a high risk level, L = Low indicates a low risk level, V indicates an increased risk level, and S indicates a decreased risk level; based on the risk level score set of each type of fire determined in step A2, the actual loss caused by each type of fire is estimated, and trapezoidal fuzzy is used to establish fuzzy grading functions for different risk levels. The trapezoidal fuzzy grading function is as follows:

[0061]

[0062] in Represents the normalized fire danger rating;

[0063] f w (r i,j ) represents the risk level score R i,j The fire danger level is F w The probability density function at time t and the order value of the fire danger degree score are obtained by fitting the fire statistical data.

[0064] A4. Establish an evaluation database to determine the danger level or the probability of different danger levels by collecting current evaluation indicators;

[0065] In the actual implementation process, based on this, the computer system can use the energy tank content and monitoring system to obtain the basic data required for the corresponding evaluation indicators, and combine the corresponding technical parameters of various fuels in the database to automatically analyze the current fire severity of different scales, and then put forward corresponding warnings. In the process of fire development, continuous tracking can also be carried out while effectively obtaining data.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for analyzing and predicting the fire hazard level of a ship energy compartment, characterized in that: The steps include: A1. Establish a fire hazard evaluation index set. Based on the fire hazard evaluation indexes given by experts or evaluation systems, screen and combine them to establish an evaluation index set X containing several evaluation indexes: X={x1,x2...x j ...,x J } where x j represents the jth evaluation index, and J represents the total number of evaluation indicators; The evaluation index set includes at least combustion index x1, energy release index x2, scale index x3, and pressure difference index x4; Among them, the combustion index Energy release index Size Index Pressure difference index m k The average mass burning rate of the kth type of fuel, where It refers to the maximum mass burning rate of the kth type of fuel in the energy compartment, C represents the flame attenuation coefficient, α k Refers to the correction factor for the kth type of fuel, D k represents the total mass of the kth type of fuel, K represents the total type of fuel; M k It refers to the combustion heat of the kth type of fuel; ρ is the average air density in the energy cabin, g is the real-time gravity acceleration in the cabin; Δσ is the average pressure difference between the energy cabin and its surrounding cabins, and V is the volume of the energy cabin; A2. Based on event annotation, obtain the danger level scores Q of various fire indicators by different experts or evaluation systems i i,j : where q i,j represents the scoring weight given by the ith expert or system for the jth evaluation index of a fire, x i,j represents the score given by expert i for indicator j; Statistical analysis of all experts or systems' scores on the danger level of various fire indicators Among them, ω i is the weight coefficient of the ith expert or system, I is the total number of experts or systems; A3. Establish a fire hazard evaluation model The danger level of each type of fire is evaluated and divided into at least seven danger levels based on the danger level: extremely dangerous, highly dangerous, relatively dangerous, ordinary dangerous, relatively small dangerous, relatively small dangerous, and extremely small dangerous, and they are marked with F respectively. VH 、F H 、F SH 、F M 、F SL 、F L 、F VL express; Where H = High indicates a high risk level, L = Low indicates a low risk level, V indicates an increased risk level, and S indicates a decreased risk level. According to the risk level scores of various fires determined in step A2 and the estimated losses actually caused by various fires, trapezoidal fuzzy is used to establish fuzzy grading functions for different risk levels. The trapezoidal fuzzy grading function is as follows: in Represents the normalized fire danger rating; f w (r i,j ) indicates that the risk level is rated as R i,j And the fire danger level is F w The probability density function at the time t represents the fire danger level score order value, which is obtained by fitting the fire statistical data; A4. Establish an evaluation database and determine the danger level or the probability of different danger levels by collecting current evaluation indicators.

2. The method for analyzing and predicting the fire hazard level of a ship energy compartment according to claim 1 is characterized in that: The step A1 also includes an index processing step for dealing with the fire hazard level of the closed ship environment, and the specific steps include adding the following evaluation indexes according to the ship conditions: Considering the thermal radiation value index of the energy cabin material and the personnel, the evaluation index y1 considering the thermal radiation of the fuel is obtained, and: L k The heat radiation distance of fuel k that can cause damage to the energy tank or personal injury, L′ k represents the straight-line distance between the mass center of the fuel k and the energy cabin or the personnel in the cabin, T k It represents the flame temperature when fuel k is burning, and T0 is the flame temperature when the preset reference fuel is burning.

3. The method for analyzing and predicting the fire hazard level of a ship energy compartment according to claim 2 is characterized in that: It also includes considering the impact of changes in the internal and external pressure and oxygen content of the energy cabin, and obtaining the fuel-air impact index y2 that considers the impact of fuel on oxygen and pressure, and: in It represents the air volume change caused by the combustion of unit mass of fuel k.

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