Value of combustion fake people in thermal protection clothing

For decades, various scholars have carried out a series of research on the thermal protection of clothing, including the simulation of different firefield conditions, evaluation and selection of flame retardant fabrics, the impact of protective performance, and protection Work-of-heat transfer mechanism analysis, etc.

Simulation of different firefields
Compared with the small-scale fabric test method, the advantage of the fake person test is that it can simulate a variety of firefield conditions, including different flame sizes and human activities. Level, etc. According to ASTMF1930-2000 and ISO 13506-2008, the combustion dummy test device typically analog heat source heat is 84 kW / m2. In practice, according to specific research purposes, different fire coverage can be simulated. The proposed is not that the flammable anti-care clothing must be taken by 84 kW / m2 heat flow. In most cases, the dressers may just work around the flame, and radiation is the most important heat transfer method. For the semi-ordinary work of the sea military, it is not economically or not practical to design garments in accordance with the standards of the THERMAMAN test. So he improved the fake person testing device and designed the sliding device to simulate the general fire environment that occurred on the ship. The fake person can still pass through the flame at the door of the combustion chamber to test the thermal protection of clothing under radiation and convection conditions.
Andrew [22] improved the suspension device of the literature [17], so that the fake person can wear a hat and breathing device, and obtain the speed of thermo-man specific combustion time by setting the fake person through the speed of the fire. The same heat flow. The overall protective clothing performance test under dynamic conditions was simulated, so that the test conditions were more closely close.
Evaluation and Selection of Flame-retardant fabrics
TPP, etc., since the fabric is completely fixed, it cannot be reflected in the dynamic reaction during the test, such as thermal shrinkage. In the combustion dummy test, the garment naturally wear in the human body, and the dynamic changes of fabrics in the combustion process can be observed. In the literature [8], the air layer made of NOMEX fabric was 40% in the air layer of 4 S's flash shirt, and nearly 90% of the legs were contracted; the literature [23] "Donghua Fire" test, Observing the NOMEX fabric production was severely contracted from the third S (shown in Figure 4). Therefore, the combustion dummy can provide more reference information for the test of the fabric. In addition, in TTP, RPP test, the fabric is placed horizontally, and the clothing is in the human body, it is vertical, so the direction of heat transfer is different. Crown et al [24] designed a cylindrometer to simulate the state of clothing, andIt is compared with different test methods (ASTM, CGSB, and ISO), and is a cylindrical measurement, and the protective performance of the fabric display is degraded. Therefore, it is more objective and practical to use the combustion dummy to evaluate fabrics.
In the study of the anti-fake fake people, Behnke et al. [25] compared the THERMO-LEG test system of still fake people and live. Thermo-LEG can simulate the scene of the victim to flee the fire scene by simulating running motion to test the protection performance of the material under dynamic conditions. The results show that maintaining the strength and integrity of the clothing is more important than protectiveness in the case of long-term dynamic contact flame. The NOMEXITON and KEVLAR100 performance are better than fr Cotton and Fr Wool.
Dale et al. [26] compares the protection properties of flame retardant fabrics under non-hot flow conditions. Fabric a flame retarded fabric, such as Nomex @ IIIA and the blended fabric of Kevlar and PBI, the percentage of burns increased steadily with the increase of heat flow, while cotton flame retardant finishing fabric, increased to 5. 97 ~ 8. 36 CAL When / cm2, the burn area has increased, and the original
is that the thermal decomposition temperature of the cotton flame retardant finishing fabric is relatively low. Rossi et al [27] uses the dummy to study the relationship between the combustion spread velocity (FRP) of natural and synthetic fibers to reach the time of burn time. It is found that the maximum amount of FRP has the shortest time, and for some combined fibers, that is, the time that the FRP is lower to 5 degrees of burns, which may be related to the thermal transfer performance of the fabric.

The effect of clothing style structure on protective performance
In addition to the flame retardant heat resistance of the fabric itself, the garment style structure also has a heavy effect on protectiveness. The air-air layer is thermally transmitted, which in turn affects the time and area of the dimensions, and the different clothing styles determine the different distribution of air levels. Kim et al [28] performs three-dimensional scan for the fake people before and after the assembly, and the distribution of the gap is quantified, and the relationship between burns and clothing is analyzed by combustion dummy experiment. Studies have shown that the distribution of clothing has a certain impact on the protective performance of the clothing, and the part of the gap between the shoulder and the chest is more likely to cause burns.
The air layer distribution of the clothes of different types of fire prevention clothing was also measured with a three-dimensional body scanner, and the relationship between burns and air layers was established. The best air layer thickness was 7 to 8 mm with numerical model. More than this value, the convection in the air layer, the protective performance is no longer increased as the air layer increases.
TAnnie et al. [30 - 31] studied the difference in women's anti-care and men's anti-care protection. It is found that the air layer of the woman's garment is very large, but does not improve the protection performance, mainly because of the impact of convection. And due to the rays of the part, heat caused by heat on the buttocks, and the buttocks were severely burned. The men's clothing is designed by a single layer fabric design due to the waist, and the waist burn is serious.
The style of clothing has an important impact on its protection performance. Through the combustion of the fake people, the actual wearing situation of the human body in the fire is of great significance for the structure of flame retardant protection equipment.

Flame-retardant protective clothing heat transfer mechanism analysis
By combustion dummy simulates different combustion conditions, the sensor monitors the changes in the surface temperature of the human skin and the change in heat flow, and the different boundary conditions can be used for flame retardant equipment. Delivery mechanism research provides important research methods.
established a numerical model of single-layer clothing heat transfer in the flashfire, studied the thermophysical properties of fabrics, the characteristics of flashfire environment, fabric contraction and fit factor, the initial temperature and test environment on thermal protection performance forecast results. The impact and verify the experiment with Pyroman.
Matej et al. [32] established a heat transfer model and provided an effective algorithm for calculating the reverse heat conduction, the temperature data obtained based on the fake person combustion surface sensor, using the supplied algorithm program to obtain the heat flow of the skin, Further, the distribution of burns is obtained. They also studied the influence of the parameters and thickness of the skin of the skin [33]. Based on the temperature data acquired by the dummy surface sensor in the combustion experiment, by changing the parameters of the skin, including the heat generating coefficient, heat capacity, and each layer thickness, resulting in burn points under different parameters. As a result, it was found that the variation of the parameters of the leather layer determined the final burns distribution.

Burning fake people's application prospects and prospects
Improvement
1) Further improve sensors, closer to the nature of true skin. In combustion dummy's body design, the selection of sensors is an important part. The currently used sensors mainly have copper-sensors and skin simulation sensors, but they have deficiencies. The heat absorbing speed of the copper sensor is different from the skin. The temperature of the skin is rising than the copper sheet
sensor; the skin analog sensor's density, heat capacity, heat capacity, and the skin have a certain gap [17] . Therefore, the sensor is therefore important to the heat absorption capacity of the skin, which is of great significance for improving the accuracy of the combustion dummy test. 2) Combustion fake people combined with the sweating dummy, comprehensively evaluate protective clothing. Under the current test conditions, both the TPP test device or the combustion dummy test system cannot simulate water vapor delivery. Research shows that water vapor has an important impact on protective performance, and is an irreparable factor [34- 35]. The firefighter is often wet during the fire extinguishing process, and the firefighters itself sweat. If you can improve the burning dummy, you can simulate the sweat state, that is, the perfect combination of the combustion dummy and the sweating dummy can provide more objective for protective clothing, whether it is protective performance test or comfortable performance test. Test Results.
3) The intelligent study of combustion fake people is more realistic to simulate the fire fire. Most of the internationally burning fake people in the world cannot be active. The difference in activity level must affect the test results of the protection performance, so the evaluation and research of thermal protection performance cannot be limited to the situation in still state. If you give a smart system, you can actually simulate the actual fire prevention situation of firefighters like the livefriend, and more objectively evaluate the fire service.
4) Real reappearance of various firefield conditions and broaden the research areas of flame retardant protective clothing. The current combustion dummy system can only simulate a routine fire environment, but in addition to fire in the fire, there may be water, flue gas, poison, improve the combustion dummy test system, so that it can simulate fire and simulate water, poison, Flue gas fire environment can broaden the research field of flame retardant protective clothing.
The broadening of the application
Combustion dummy test technology is the best technology of internationally recognized objective evaluation of overall thermal protection performance, as an international front-edge cutting-edge technology, such as bio-physics, biophysics, etc. Scientific value is significant. In the future, its application is mainly following:
1) Test and analyze clothing. Using the combustion dummy test system, it can carry out the evaluation and influencing factors of all kinds of fire-fighting equipment, military uniforms and other protective equipment. Shorten the new material and equipment research cycle, improve the research level, and promote the development of individual protective equipment.
2) Research the human body. Using the combustion dummy test system, creating a real flame clothing skin environmental conditions, monitoring the heat flow and temperature changes in the fake human skin during the combustion process, providing an effective data foundation for biophysical research on further human skin tissue burn analysis.
3) Safety protection. In addition to fire protection services, ordinary clothing also requires certain flame retardancy. The combustion dummy can not only be used in military protective clothing tests, but also have important research significance for the heat damage caused by equipment research and development of thermal protective fabrics, clothing, etc. in civil use.

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