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Forest fires are characterized by hidden ignition points, rapid spread, large burning areas, intense flames, and significant influence from meteorological conditions. Due to the complexity of terrain and surrounding environments, conventional firefighting equipment often struggles to reach the core ignition areas from the ground, greatly increasing the difficulty and cost of forest fire prevention and control. Fire suppression munition, due to their ability to control fires at medium and long distances, are commonly used in the field of forest firefighting. This paper conducts research and experiments on the development of new fire suppression munition after analyzing the advantages and disadvantages of current fire suppression munition, aiming to effectively suppress forest fires. Through experiments, it was found that the fire suppression aerial munition were stable and reliable throughout the entire test process. The dispersal range and concentration of the fire suppressant after explosion met the expected requirements. Good suppression effects were achieved in field tests on large ground fires and crown fires, with flames being extinguished and no reignition occurring within 10 min.

Suppression of forest fires has been one of the important research directions in the field of fire safety, ammonium phosphate and its mixture of inhibitors commonly used in solid combustible fires, for forest fire scenarios, also has a good fire suppression effectiveness, inexpensive and easy to store, but also the current suppression of forest fires is one of the main inhibitors. However, there are few studies on the interaction between ammonium phosphate and forest fires. In this paper, to facilitate the study, we enter the previous research ideas for gas fires, reduce the scale of the research object, establish a small-sized simplified flame model for suppressing wood fires, take red pine wood as the research object, analyze the pyrolysis gas components after high-temperature pyrolysis, and construct the Cup-burner experimental system, together with an improved powder delivery control system, so that the process of NH4H2PO4 powder quenching fuel flames such as red pine pyrolysis gas at 350 °C, 450 °C and 550 °C was well presented on this device. It was found that the flame morphology was not only related to the gas composition but also the amount of NH4H2PO4 powder added and the particle size; the Minimum fire extinguishing concentration(MEC) value was not only related to the gas composition but also the particle size of NH4H2PO4 powder. This is because the CO2 content decreases and the H2 and CH4 content increase significantly in the gas composition at 550 °C compared to the 450 °C gas composition. Among the same pyrolysis gas components, the MEC value gradually increased as the particle size of NH4H2PO4 powder decreased, and the MEC value of 30 μm–40μm particle size powder was the lowest, and the difference between the particle size MEC value and the other two particle sizes was large, while the difference between the MEC values of 20 μm–30μm particle size powder and 10 μm–20μm particle size powder was small; according to the Cup-burner test The chemical thermodynamic analysis was carried out according to the results of the Cup-burner test to obtain the proportion of NH4H2PO4 powders playing a physical role in fire extinguishing. When NH4H2PO4 powder is involved in syngas/air combustion, the end product is P2O5 and xsp = 2.35%. When the end product is HPO3, xsp = 7.29%. The products were collected after the interaction of NH4H2PO4 powder with the synthesis gas flame, and the analysis of the products revealed that the products were sticky and not dry solids, and the material analysis of them revealed that they contained more HPO3 and its mixture, which shows that the physical heat absorption played a greater role when NH4H2PO4 powder interacted with the synthesis gas flame.

In combustion research, the laminar flame speed (SL) is an important basis for the study of fuel combustion and mechanism verification. A large number of studies have been done on various combustibles, mostly focusing on gas and liquid combustibles, but less on solid combustibles, and the SL of solid combustibles cannot be measured directly and effectively by conventional methods. This paper uses red pine wood as the object of study, analyses the pyrolysis gas components after high-temperature pyrolysis, and uses the Bunsen burner experimental system to study the SL of pyrolysis gas, and obtains the laminar flame speed (SL) of the gas-phase flame when burning red pine wood, which has certain guiding significance for the study of the laminar flame speed (SL) of solid combustibles. In this paper, firstly, the pyrolysis gas products of red pine wood were analyzed by TG-DSC as well as GC/MS, and it was found that the direct reaction was the most violent at 210°C–410 °C, and the reaction rate gradually levelled off after 410 °C. It was also found that the gas mainly consisted of H2, CO2, C2H4, CO, CH4, C2H6, C3H6 and C3H8, accounting for more than 98%, and with the pyrolysis Secondly, the laminar flame speed (SL) of the gas products was investigated using the Bunsen burner, and it was found that the laminar flame speed (SL) of the pyrolysis gases gradually increased with the increase of the pyrolysis temperature, with 15.7 cm-s−1, 32.94 cm-s−1 and 36.89 cm-s−1 for the pyrolysis gases at 350 °C, 450 °C and 550 °C, respectively Finally, numerical simulations were carried out to investigate the effects of initial temperature and altitude induced changes in air pressure and oxygen concentration on the laminar flame speed of the gas products, and it was found that the laminar flame speed of pyrolysis gases gradually increased with increasing initial temperature and decreased with increasing altitude. The effect of hydrocarbon gases on the SL-max of CH4 is essentially linear in the concentration range of 40%, while the effect of H2, CO and CO2 is essentially in the quadratic polynomial distribution.

The suppression of forest fires has been one of the important research directions in the field of fire safety, fine water mist because of the advantages of easy access to materials, low price and no pollution to become one of the commonly used inhibitors to suppress forest fires, so previous research done for fine water mist suppression of forest fires, mostly for the macro level of fire suppression effectiveness and methodological research, for fine water mist and forest fire interaction mechanism research is less, this paper for the convenience of research, the In this paper, to facilitate the study of red pine wood as the research object, after high temperature pyrolysis analysis of pyrolysis gas components, the construction of fine water mist suppression of red pine wood pyrolysis gas flame Bunsen burner experimental system, study the effect of different additions of fine water mist on the laminar flame speed (SL) of red pine wood pyrolysis gas flame, and the use of chemkin software to study the mechanism of interaction between fine water mist and red pine wood pyrolysis gas flame, on the study of the interaction between fine water mist and red pine pyrolysis gas flames using chemkin software has some implications for the suppression of forest fires. In this paper, the pyrolysis gas products of red pine wood were firstly analysed by TG-DSC as well as GC/MS and found to consist mainly of H2, CO2, C2H4, CO, CH4, C2H6, C3H6 and C3H8, accounting for more than 98% of the gases. The Bunsen burner experimental system constructed for the suppression of red pine pyrolysis gas flames by fine water mist revealed that the flame height gradually increased with increasing fine water mist addition and the flame cone angle gradually decreased, indicating that the flame speed was gradually decreasing with increasing fine water mist addition. It was observed that the flame height did not change significantly at low equivalents as the amount of extinguishing agent added increased, indicating that the fine water mist had a weak pro-ignition effect on the red pine pyrolysis gas/air system. The influence of the gas content on the flame promotion effect of the fine water mist was investigated by chemkin software. It was found that the ratio of CO/H2 in the pyrolysis gas composition of red pine wood will determine the strength of the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame, the higher the ratio of CO/H2, the stronger the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame, and conversely the lower the ratio, the weaker the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame.

Two-dimensional (2D) organic–inorganic hybrid perovskites (OIHPs) have drawn increased attention due to rich physical properties such as ferroelectricity and photovoltaic properties. Nevertheless, it is challenging to discover novel 2D OIHPs within the vast chemical composition space. Herein, a diagrammatic machine learning model was employed to improve this issue. We collected 179 OIHPs with a variety of organic cations and screened out 6 features from 10,622 descriptors. Subsequently, a decision tree model was created to predict the dimensionality of OIHPs, achieving a LOOCV accuracy of 0.94 and a test accuracy of 0.89, respectively. Then, one candidate from a virtual space with 8256 samples was successfully synthesized, which was consistent with the prediction of the model. Finally, three rules were produced by visualization of the tree structure to generally discriminate 2D from non-2D OIHPs. It is believed that the diagrammatic model has reliability in identifying 2D OIHPs and will serve further property studies of OIHPs in the future.