Aqueous film-forming foam extinguishing agent sealing performance test optimization method based on orthogonal test

Abstract

The invention relates to the technical field of fire extinguishing and rescue, and particularly discloses an aqueous film-forming foam extinguishing agent sealing performance test optimization method based on an orthogonal test, and the method comprises the steps: selecting factors and factor levels which influence the sealing performance of an aqueous film-forming foam extinguishing agent, carrying out the sealing performance test of the aqueous film-forming foam extinguishing agent, and obtaining a test result; calculating a range value of each factor according to a test result; according to the range value, main factors and secondary factors influencing the sealing performance of the aqueous film forming foam extinguishing agent are determined; according to the main factor, the secondary factor and the molecular level, determining the sealing performance test condition parameters of the aqueous film-forming foam extinguishing agent, and forming a sealing performance standardization test scheme of the aqueous film-forming foam extinguishing agent. According to the invention, main factors and secondary factors influencing the sealing performance of the aqueous film-forming foam extinguishing agent can be determined, and proper sealing performance test condition parameters of the aqueous film-forming foam extinguishing agent are selected to form a repeatable and standardized sealing performance test scheme of the aqueous film-forming foam extinguishing agent.

Description

Technical Field

[0001] The present invention relates to the technical field of fire extinguishing and rescue, and in particular to an optimization method for testing the sealing performance of an aqueous film-forming foam fire extinguishing agent based on an orthogonal test. Background Art

[0002] Foam fire extinguishing agents are the most important fire extinguishing agents for flammable liquid fires and are widely used in firefighting locations such as petrochemical storage tanks, airports, docks, and ships. Aqueous film-forming foam fire extinguishing agents, due to their excellent performance, are the most commonly used type of foam fire extinguishing agent in fire management. For liquid fires, the foam's ability to contain liquid fuel vapors is closely linked to the timing and volume of foam injection during the firefighting process, significantly impacting firefighting efficiency.

[0003] In recent years, scholars both domestically and internationally have conducted research on the containment performance of aqueous film-forming foam fire extinguishing agents against liquid fuel vapors. For example, Chinese utility model patent number CN 221224700 U, titled "An Integrated Foam Fire Extinguishing Agent Containment Performance Test Device," is available. Reference 1: Schaefer T, Dlugogorski BZ, Kennedy EM. Vapour Suppression of N-Heptane with Fire Fighting Foams Using Laboratory Flux Chamber [J]. 2007. Reference 2: Hinnant KM, Giles SL, Ananth R. Measuring Fuel Transport through Fluorocarbon and Fluorine-Free Firefighting Foams [J]. Fire Safety Journal. 2017, 91(jul.): 653-661. Reference 3: Wang Yaoshuai. Research and Validation of a Test Method for Oil Vapor Containment of Foam Fire Extinguishing Agents [D]. Civil Aviation Flight University of China, 2020. For water-forming foam fire extinguishing agents, low-expansion foams of different multiples less than 20 times can be produced according to the change in the gas-liquid ratio, and the temperature of the foam solution will also affect the foaming multiple of the foam fire extinguishing agent. Different foaming multiples will have different sealing effects on fuel vapor. At the same time, the thickness of the foam coverage of the water-forming foam fire extinguishing agent on the fuel will also affect its sealing performance. In addition, from the perspective of fuel, there are obvious differences in the destructive effects of fuel type and fuel temperature on foam fire extinguishing agents, which directly affect the sealing performance of foam fire extinguishing agents on fuel vapor. However, the variables examined in the relevant studies are single, and no test research on the fuel vapor sealing performance of water-forming foam fire extinguishing agents under multi-factor conditions has been conducted, nor has the key control factors for the fuel vapor sealing performance of water-forming foam fire extinguishing agents been proposed. It is impossible to guide the establishment of repeatable and standardized test methods for the sealing performance of water-forming foam. Summary of the Invention

[0004] The present invention aims to address the problem that many factors influence the sealing performance of aqueous film-forming foam fire extinguishing agents on liquid fuel vapors, but related studies have examined a single variable and failed to identify key control factors for the sealing performance of aqueous film-forming foam fire extinguishing agents on fuel vapors, thus failing to guide the establishment of a repeatable and standardized testing method for the sealing performance of aqueous film-forming foam fire extinguishing agents. To this end, the present invention provides an optimization method for testing the sealing performance of aqueous film-forming foam fire extinguishing agents based on orthogonal experiments. This method can determine the primary and secondary factors affecting the sealing performance of aqueous film-forming foam fire extinguishing agents, select appropriate test conditions and parameters for the sealing performance of aqueous film-forming foam fire extinguishing agents, and form a repeatable and standardized testing method for the sealing performance of aqueous film-forming foam fire extinguishing agents.

[0005] The present invention provides a method for optimizing the sealing performance test of an aqueous film-forming foam fire extinguishing agent based on an orthogonal test, and the technical solution adopted is as follows: comprising the following steps: Step 1: Select factors that affect the sealing performance of aqueous film-forming foam fire extinguishing agents, select factor levels for each of the factors, and construct an orthogonal test table based on the factors and factor levels; Step 2: Conduct a sealing performance test of the aqueous film-forming foam fire extinguishing agent according to the orthogonal test table to obtain test results; Step 3: Calculate the range value of each factor according to the test results; Step 4: Determine the main factors and secondary factors that affect the sealing performance of the aqueous film-forming foam fire extinguishing agent based on the range value; Step 5: Based on the main factors and secondary factors, and their molecular levels, determine the test condition parameters for the sealing performance of the aqueous film-forming foam fire extinguishing agent, and form a standardized test plan for the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0006] Furthermore, in step 1, the factors include at least three of the following: foaming magnification, foam solution temperature, foam thickness, fuel type, and fuel temperature.

[0007] Furthermore, in step 1, the factor levels of the foaming multiple include 7 times, 10 times and 15 times, the factor levels of the foam solution temperature include 15°C, 20°C and 25°C, the factor levels of the foam thickness include 1 cm, 5 cm and 10 cm, the factor levels of the fuel type include solvent oil for rubber industry, n-heptane and cyclohexane, and the factor levels of the fuel temperature include 20°C, 40°C and 60°C.

[0008] Furthermore, in step 2, the judgment index of the orthogonal test is determined, and then the sealing performance test of the aqueous film-forming foam fire extinguishing agent is carried out according to the orthogonal test table.

[0009] Furthermore, in step 3, the calculation process of the range value is: Calculate the average value of the test results at each factor level of the factor according to the test results. The range value of the factor is obtained by subtracting the minimum value from the maximum value of the average values ​​of all test results corresponding to the factor.

[0010] Furthermore, the range value represents the fluctuation of the test results of the factor at different factor levels. The larger the range value, the greater the impact of the factor on the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0011] Furthermore, in step 4, the two factors with the largest range values ​​are selected as primary factors, and the remaining factors are selected as secondary factors.

[0012] Furthermore, the test condition parameters for the sealing performance of the aqueous film-forming foam fire extinguishing agent include variable condition parameters and fixed condition parameters. The factor level of the main factor is selected as the variable condition parameter, and a factor level of the secondary factor is randomly selected as the fixed condition parameter.

[0013] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: 1. The present invention avoids full-scale experiments and random errors by designing orthogonal experiments. This allows the primary controlling factors affecting the sealing performance of aqueous film-forming foam fire extinguishing agents to be determined while significantly reducing the number of experiments, significantly reducing the time required for the design. The present invention uses the range of fluctuations in test results at different factor levels to determine the primary and secondary factors affecting the sealing performance of the aqueous film-forming foam fire extinguishing agent based on the range of these fluctuations, thereby determining the primary and secondary factors affecting the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0014] 2. The present invention proposes a standardized test scheme for the sealing performance of aqueous film-forming foam fire extinguishing agents, which can effectively evaluate the sealing performance of the formulations in the development process of aqueous film-forming foam fire extinguishing agents, improve the efficiency of formula screening, and also provide a scientific method for performance comparison between aqueous film-forming foam fire extinguishing agent products, thereby providing technical support for the development of foam fire extinguishing agent formulations and product testing.

[0015] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a flow chart of the method provided by the present invention. DETAILED DESCRIPTION

[0018] To make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0019] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0020] The following combination Figure 1 The present invention is further described in detail, and a method for optimizing the sealing performance test of an aqueous film-forming foam fire extinguishing agent based on an orthogonal test is described. In this embodiment, Figure 1 As shown, a method for optimizing the sealing performance test of an aqueous film-forming foam fire extinguishing agent based on an orthogonal test is provided, comprising the following steps: Step 1: Select factors that affect the sealing performance of aqueous film-forming foam fire extinguishing agent, select factor levels for each of the factors, and construct an orthogonal test table based on the factors and factor levels.

[0021] In this embodiment, five factors are selected, including foaming multiple, foam solution temperature, foam thickness, fuel type and fuel temperature.

[0022] Then, three factor levels were selected for each factor, specifically: The factor levels of the foaming ratio include 7 times, 10 times and 15 times, the factor levels of the foam solution temperature include 15°C, 20°C and 25°C, the factor levels of the foam thickness include 1cm, 5cm and 10cm, the factor levels of the fuel type include solvent oil for rubber industry, n-heptane and cyclohexane, and the factor levels of the fuel temperature include 20°C, 40°C and 60°C.

[0023] Depending on the actual situation, other factors and corresponding factor levels can also be selected. However, in order to smoothly proceed with the subsequent steps, the number of factors should not be less than 3. For ease of description, this embodiment selects 3 factor levels for each factor. Depending on the actual situation, a larger number of factor levels, such as 5, can also be selected for each factor.

[0024] Step 2: Determine the judgment index of the orthogonal test, carry out the sealing performance test of the aqueous film-forming foam fire extinguishing agent according to the orthogonal test table, and obtain the test results.

[0025] In this example, the determination criterion is the time it takes for the fuel vapor concentration to reach 25% of the lower explosive limit (25% LEL). The containment performance test for aqueous film-forming foam fire extinguishing agents was conducted using an integrated foam fire extinguishing agent containment performance test device (Chinese utility model patent authorization number CN221224700U). The test results were added to the orthogonal test table in step 1, resulting in the orthogonal test results table shown in Table 1.

[0026] Table 1 Orthogonal test results

[0027] It should be noted that if orthogonal tests of all factor levels are performed, 243 tests are required, which is too many. Based on past experience, this embodiment only performed 18 tests, and each factor level of each factor was used 6 times.

[0028] Step 3: Calculate the range of each factor based on the test results. The specific process is: Step 3.1: Calculate the total value K of the test results at each factor level of the factor according to the test results. Step 3.2: Divide the total value K by the number of trials for this factor level (6 times) to get the average value K of the test results. avg ; Step 3.3: Use the average value K of all test results corresponding to the factor avg The maximum value minus the minimum value in is used to obtain the range value R of the factor. The calculation results are shown in Table 2.

[0029] Table 2 Range value analysis table

[0030] Step 4: Based on the range values, determine the main factors and secondary factors that affect the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0031] The range value represents the fluctuation of the test results of the factor at different factor levels. The larger the range value, the greater the impact of the factor on the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0032] As can be seen from the range values ​​in Table 2, the order of influence of various factors on the sealing performance of aqueous film-forming foam fire extinguishing agents is: foaming expansion > fuel temperature > foam thickness > fuel type > foam solution temperature. In this example, the two factors with the largest range values ​​were selected as primary factors, and the remaining factors were designated as secondary factors. Therefore, the primary factors are foaming expansion and fuel temperature, while the secondary factors are foam thickness, fuel type, and foam solution temperature.

[0033] Step 5: Based on the main factors and secondary factors, and their molecular levels, determine the test condition parameters for the sealing performance of the aqueous film-forming foam fire extinguishing agent, and form a standardized test plan for the sealing performance of the aqueous film-forming foam fire extinguishing agent.

[0034] The test condition parameters for the sealing performance of the aqueous film-forming foam fire extinguishing agent include variable condition parameters and fixed condition parameters. The factor level of the main factor is selected as the variable condition parameter, and a factor level of the secondary factor is randomly selected as the fixed condition parameter.

[0035] After orthogonalizing the multiple factor levels of multiple primary factors, multiple sets of parameters are formed. Each set of parameters, together with the factor levels of all secondary factors, forms a set of test condition parameters. These multiple sets of test condition parameters form a standardized test plan for the containment performance of aqueous film-forming foam fire extinguishing agents. There can be one or more secondary factors, and each secondary factor has only one factor level.

[0036] In this embodiment, based on the primary and secondary factors determined in step 4, for the foaming multiple, the factor levels of the orthogonal experimental design were selected as variable conditions, that is, the effective sealing time of the aqueous film-forming foam fire extinguishing agent on fuel vapor at 7 times, 10 times, and 15 times the foaming multiple was examined; for the fuel temperature, the factor levels of the orthogonal experimental design were selected as variable conditions, that is, the effective sealing time of the aqueous film-forming foam fire extinguishing agent on fuel surfaces at 20°C, 40°C, and 60°C was examined; for the foam thickness, fuel type, and foam solution temperature, one factor level from the orthogonal experimental design was randomly selected as the fixed condition parameter of the final scheme, for example, the foam thickness was fixed at 5 cm, the fuel type was fixed at n-heptane, and the foam solution temperature was fixed at 20°C. The final standardized test scheme for the sealing performance of the aqueous film-forming foam fire extinguishing agent is shown in Table 3.

[0037] Table 3 Standardized test scheme for the sealing performance of aqueous film-forming foam fire extinguishing agents

[0038] Finally, it should be noted that the above 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 with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test, characterized in that: The following steps are involved: Step 1: Select factors that affect the sealing performance of aqueous film-forming foam fire extinguishing agent, select factor levels for each of the factors, and construct an orthogonal test table based on the factors and factor levels; Step 2: According to the orthogonal test table, carry out the sealing performance test of the aqueous film-forming foam fire extinguishing agent to obtain the test results; Step 3: Calculate the range value of each factor according to the test results; Step 4: According to the extreme difference value, determine the main factors and secondary factors affecting the sealing performance of the aqueous film-forming foam fire extinguishing agent; Step 5: Based on the main factors and secondary factors, and their molecular levels, determine the test condition parameters for the sealing performance of the aqueous film-forming foam fire extinguishing agent, and form a standardized test plan for the sealing performance of the aqueous film-forming foam fire extinguishing agent.

2. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1, characterized in that: In step 1, the factors include at least three of the foaming multiple, the foam solution temperature, the foam thickness, the fuel type and the fuel temperature.

3. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 2, characterized in that: In step 1, the factor levels of the foaming multiple include 7 times, 10 times and 15 times, the factor levels of the foam solution temperature include 15°C, 20°C and 25°C, the factor levels of the foam thickness include 1cm, 5cm and 10cm, the factor levels of the fuel type include solvent oil for rubber industry, n-heptane and cyclohexane, and the factor levels of the fuel temperature include 20°C, 40°C and 60°C.

4. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1, characterized in that: In step 2, the judgment index of the orthogonal test is determined, and then the sealing performance test of the aqueous film-forming foam fire extinguishing agent is carried out according to the orthogonal test table.

5. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1, characterized in that: In step 3, the calculation process of the range value is: According to the test results, the average value of the test results at each factor level of the factor is calculated. The range value of the factor is obtained by subtracting the minimum value from the maximum value of the average values ​​of all test results corresponding to the factor.

6. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1 or 5, characterized in that: The range value indicates the fluctuation of the test results of the factor at different factor levels. The larger the range value, the greater the influence of the factor on the sealing performance of the aqueous film-forming foam fire extinguishing agent.

7. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1 or 5, characterized in that: In step 4, the two factors with the largest extreme values ​​are selected as the main factors, and the remaining factors are selected as secondary factors.

8. The method for optimizing the sealing performance test of aqueous film-forming foam fire extinguishing agent based on orthogonal test as claimed in claim 1, characterized in that: The test condition parameters for the closure performance of the aqueous film-forming foam fire extinguishing agent include variable condition parameters and fixed condition parameters. The factor level of the main factor is selected as the variable condition parameter, and a factor level of the secondary factor is randomly selected as the fixed condition parameter.

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