Journal articles: 'Explosion Phenomenon'

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Kimura, Satoshi, Hidehiro Hata, Tetsuyuki Hiroe, Kazuhito Fujiwara, and Hideaki Kusano. "Analysis of Explosion Combustion Phenomenon with Ammonium Nitrate." Materials Science Forum 566 (November 2007): 213–18. http://dx.doi.org/10.4028/www.scientific.net/msf.566.213.

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In this study, an explosion combustion phenomenon of ammonium nitrate (ρ=1.7kg/cm3) was used instead of the explosive PETN and the ultra-high-speed destruction phenomenon of aluminum cylinder was analyzed. The mix powder obtained by mixing aluminum powder (ρ=2.7kg/cm3) and ammonium nitrate was used instead of the explosive PETN, and an explosive combustion phenomenon was generated using copper wire explosion by high-voltage capacitor bank (40kV, 12.5 /F). Ammonium nitrate and aluminum powder are kneaded in a combination ratio of 5 : 1 in mass. An aluminum cylinder was destroyed by the phenomenon. The experiments were conducted using various diameters of ammonium nitrate particle and the photographs of the phenomenon were taken by the high-speed camera (IMACON468) and the high-speed video camera (HPV-1). The fragments of aluminum cylinder were collected and their dimensions were measured. The explosion phenomenon and fragments were compared with the result by explosive PETN. This paper presents these experiments and analysis result. And, hydro codes have been applied to simulate the deformation behavior of the aluminum cylinder.

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Mubarok, Muhammad Arif Husni, Aditya Rio Prabowo, Teguh Muttaqie, and Nurul Muhayat. "Dynamic Structural Assessment of Blast Wall Designs on Military-Based Vehicle Using Explicit Finite Element Approach." Mathematical Problems in Engineering 2022 (September 13, 2022): 1–22. http://dx.doi.org/10.1155/2022/5883404.

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Explosion load studies are an essential part of shield engineering design. This is especially true for explosion-proof plates, which are used in order to reduce the impact of explosions, which have the potential to cause substantial damage to structural elements. The purpose of this study is to detail the explosion phenomenon and the response of sandwich panel structures under explosive loading. The finite element method (FEM) is used to model the dynamic structural response to explosions. Explicit finite element modeling and analysis are performed using ABAQUS CAE software. An air explosion simulation code is used to determine the blast load on the lower skin plate of a test panel on a typical armored personnel vehicle. Structural analysis is carried out with respect to displacement, von-Mises stress, and internal kinetic energy. Three variations of explosive loads are considered in the simulation in order to better compare the responses of the structures. Three different design variants and materials are considered, including honeycomb, stiffener, and corrugated geometric models and mild steel, medium carbon steel, and alloy steel materials. The results provided by this study pave the way toward the development of guidelines for the design of lightweight structural reinforcement elements.

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Li, Dong, Shijie Dai, and Hongwei Zheng. "Investigation of the explosion characteristics of ethylene-air premixed gas in flameproof enclosures by using numerical simulations." Thermal Science, no. 00 (2022): 189. http://dx.doi.org/10.2298/tsci220905189l.

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Flameproof enclosures are widely installed as safety equipment at dangerous industrial sites to reduce ignition risks. However, electrical components typically installed in such flameproof enclosures for the production process can cause ignition and compromise the safety of the enclosures. Thus, in such cases, the explosive characteristics of the flameproof enclosures is severely affected. Accidental gas explosions in industrial sites rarely occur under standard operating conditions. Premixed gas explosions in flameproof shells are complex processes. A 560 mm ? 400 mm ? 280 mm flameproof enclosure commonly used in industrial sites was used to investigate the phenomenon. The explosion characteristics of ethylene-air premixed gas in the flameproof enclosure was simulated using Fluent software to investigate the influences of ignition source location, ignition source energy, ambient temperature, and obstacles on the maximum explosion pressure, maximum explosion pressure rise rate, and maximum explosion index of the flameproof enclosure. The results revealed that the surface area of heat exchange considerably influences the maximum explosion pressure of the flameproof enclosure. The larger the ignition energy is, the larger the maximum explosion pressure value, the maximum rate of explosion pressure rise, and the maximum explosion index of the flameproof enclosure are. With the increase in the ambient temperature, the maximum explosion pressure decreased, whereas the maximum rate of explosion pressure rise and the maximum explosion index exhibited limited change. The results of this study provide theoretical guidance for the design and suppression of flameproof enclosures.

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Hirai, Eiko, Joho Tokumine, Alan Kawarai Lefor, Shinobu Ogura, and Miwako Kawamata. "Bladder Explosion during Transurethral Resection of the Prostate with Nitrous Oxide Inhalation." Case Reports in Anesthesiology 2015 (2015): 1–3. http://dx.doi.org/10.1155/2015/464562.

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Bladder explosions are a rare complication of transurethral resection of the prostate. We report a patient who suffered a bladder rupture following transurethral resection of the prostate. Although explosive gases accumulate during the procedure, a high concentration of oxygen is needed to support an explosion. This rare phenomenon can be prevented by preventing the flow of room air into the bladder during the procedure to maintain a low concentration of oxygen inside the bladder.

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Antonov, Dmitrii V., Roman M. Fedorenko, and Pavel A. Strizhak. "Micro-Explosion Phenomenon: Conditions and Benefits." Energies 15, no. 20 (October 18, 2022): 7670. http://dx.doi.org/10.3390/en15207670.

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Adding water to fuel droplets is known to lead to puffing and micro-explosion. Puffing and micro-explosion lead to a rapid increase in the liquid fuel surface area. This, in turn, leads to an increase in the fuel evaporation rate and the formation of a homogeneous fuel vapor/air mixture. The latter is important for improving the efficiency of combustion technologies, including those used in internal combustion engines. The effects produced by puffing and micro-explosion lead to a reduction in fuel consumption, improved fuel/air mixing, and a reduction in harmful emissions. The contributions of puffing and micro-explosion to fire extinguishing have also been discussed in many papers. In this paper, we review the state of the art in the investigation of composite droplet micro-explosion and discuss the sufficient conditions for the start of puffing/micro-explosion as well as child droplet characteristics.

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Ogunfuye, Samuel, Hayri Sezer, Furkan Kodakoglu, Hamed Farmahini Farahani, Ali S. Rangwala, and V’yacheslav Akkerman. "Dynamics of Explosions in Cylindrical Vented Enclosures: Validation of a Computational Model by Experiments." Fire 4, no. 1 (February 15, 2021): 9. http://dx.doi.org/10.3390/fire4010009.

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Recent explosions with devastating consequences have re-emphasized the relevance of fire safety and explosion research. From earlier works, the severity of the explosion has been said to depend on various factors such as the ignition location, type of a combustible mixture, enclosure configuration, and equivalence ratio. Explosion venting has been proposed as a safety measure in curbing explosion impact, and the design of safety vent requires a deep understanding of the explosion phenomenon. To address this, the Explosion Venting Analyzer (EVA)—a mathematical model predicting the maximum overpressure and characterizing the explosion in an enclosure—has been recently developed and coded (Process Saf. Environ. Prot. 99 (2016) 167). The present work is devoted to methane explosions because the natural gas—a common fossil fuel used for various domestic, commercial, and industrial purposes—has methane as its major constituent. Specifically, the dynamics of methane-air explosion in vented cylindrical enclosures is scrutinized, computationally and experimentally, such that the accuracy of the EVA predictions is validated by the experiments, with the Cantera package integrated into the EVA to identify the flame speeds. The EVA results for the rear-ignited vented methane-air explosion show good agreement with the experimental results.

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Menčík, Matej, Richard Kuracina, Zuzana Szabová, and Karol Balog. "Determination of Fire and Explosion Characteristics of Dust." TRANSACTIONS of the VŠB – Technical University of Ostrava, Safety Engineering Series 11, no. 2 (September 1, 2016): 36–42. http://dx.doi.org/10.1515/tvsbses-2016-0015.

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Abstract The aim of this paper is to approximate danger of dust clouds normally occur by determining their explosion characteristics. Nowadays, dusty environment is phenomenon in the industry. In general, about 70% of dust produced is explosive. Dust reduction in companies is the main purpose of the national and European legislative. Early identification and characterization of dust in companies may reduce the risk of explosion. It could be used to identify hazards in industrial production where an explosive dust is produced. For this purpose several standards for identification and characterization of explosion characteristics of industrial dust are being used.

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Stump, Brian W. "Constraints on explosive sources with spall from near-source waveforms." Bulletin of the Seismological Society of America 75, no. 2 (April 1, 1985): 361–77. http://dx.doi.org/10.1785/bssa0750020361.

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Abstract Spall, the tensile failure of a material due to high stress loading, has been observed in a number of contained and surface explosions. The phenomenon results in a repartition of the initial spherical explosion energy source, yielding a second energy source which is cylindrical and delayed in time. Recent spall models by Day et al. (1983) demanding conservation of momentum have shown the phenomenon to have little contribution to 20-sec surface waves. These models are extended to include the effect of the process on near-source seismograms. The spall model is constrained by observations within the nonlinear regime of the source which bound the mass, momentum, and timing of the process. Comparison of these forward models with the inverse vertical point force source inferred from seismic recordings of a bermed surface explosion yields excellent agreement. The spall model developed from the contained explosion, CHEAT, is used to create synthetic seismograms. Comparisons of these waveforms with those from a Mueller-Murphy contained explosion indicate that the waveform contribution from spall is similar in size to the spherical explosion waveform. The complete synthetic composed of the spall and explosion contribution compares favorably with observational data from the CHEAT experiment in both amplitude and energy distribution.

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Xiong, Ziming, Qinghua Zhang, Hao Lu, Shaoshuai Shi, Zewei You, Yuanpu Xia, and Lin Bu. "Evaluation and identification of dynamic strain on a blast door subjected to blast loading using fibre Bragg grating sensors." International Journal of Distributed Sensor Networks 14, no. 3 (March 2018): 155014771876686. http://dx.doi.org/10.1177/1550147718766860.

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Tunnels and subway blast doors are effective barriers to terrorist attacks and emergencies, and research into the mechanical properties of blast doors under explosive dynamic loads can improve and enhance the performance thereof. In this article, surface strain measurements on subway blast door models under dynamic load are carried out using quasi-distributed fibre Bragg grating sensors. The principle underpinning fibre Bragg grating sensing is introduced before the experiment. In the experiment, a model of an explosion-proof door was designed, and the experimental foundation pit was designed to be used to fix the explosion-proof door. Then, eight fibre Bragg grating sensors are placed at different positions on the surface of the explosion door to measure the strain at the time of explosion. Through the experiment we found that the optical fibre grating sensing system can be used under explosive loading surface strain: the strain distribution on the surface of the protective door is revealed under large dynamic strain. At the same time, the rebound effect of the protective door in the explosion was found through the strain phenomenon in double peak phenomenon. The strain distribution and rebound effect in the test results can provide a useful reference for the mechanical design of the blasting door and the strain monitoring of reinforced concrete structures under dynamic load.

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Sun, Wen Bin, Yang Jiang, and Wei Zhong He. "An Overview on the Blast Loading and Blast Effects on the RC Structures." Applied Mechanics and Materials 94-96 (September 2011): 77–80. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.77.

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An explosion is defined as a large-scale, rapid and sudden release of energy. Explosions, such as a bomb explosion within or immediately nearby a building and a gas-chemical explosion, can cause catastrophic damage on the building's frames, collapsing of walls, blowing out of large expanses of windows, and shutting down of critical life-safety systems. In fact, an explosion may result in large dynamic loads, greater than the original design loads, of many structures. Blast phenomenon and blast efforts have been made during the past several decades to develop methods of structural analysis and design to resist blast loads. The analysis and design of structures subjected to blast loads require a detailed understanding of blast phenomena and the dynamic response of various structural elements. This paper introduces different methods to estimate blast loads, also presents a comprehensive overview of the effects of explosion on RC structures.

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Tanaka, Masafumi, Wataru Daimon, and Itsuro Kimura. "Explosion phenomenon from contact of hypergolic liquids." Journal of Propulsion and Power 1, no. 4 (July 1985): 314–16. http://dx.doi.org/10.2514/3.22801.

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Shorokhova, Mariia, Nikolay Nikolsky, and Tatiana Grinchuk. "Chromothripsis—Explosion in Genetic Science." Cells 10, no. 5 (May 4, 2021): 1102. http://dx.doi.org/10.3390/cells10051102.

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Chromothripsis has been defined as complex patterns of alternating genes copy number changes (normal, gain or loss) along the length of a chromosome or chromosome segment (International System for Human Cytogenomic Nomenclature 2020). The phenomenon of chromothripsis was discovered in 2011 and changed the concept of genome variability, mechanisms of oncogenic transformation, and hereditary diseases. This review describes the phenomenon of chromothripsis, its prevalence in genomes, the mechanisms underlying this phenomenon, and methods of its detection. Due to the fact that most often the phenomenon of chromothripsis occurs in cancer cells, in this review, we will separately discuss the issue of the contribution of chromothripsis to the process of oncogenesis.

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Rylnikova, Marina, Viktor Fedotenko, and Natalia Mitishova. "Influence of structural and textural features of ores and rocks on mine dust explosion hazard during development of pyrite deposits." E3S Web of Conferences 192 (2020): 03017. http://dx.doi.org/10.1051/e3sconf/202019203017.

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In the practice of mining works, sulfide-dust explosions often occur during underground development of pyrite ore deposits: copper-zinc, lead-zinc, copper-nickel, antimony, and others. This makes it necessary to conduct researches aimed at improvement of methods for studying the explosive properties of sulfide dust and development of industrial and environmental safety requirements for mining operations. Currently, there is no generally accepted state-approved regulatory procedure for assessment of sulfide dust explosion hazards during underground mining operations in Russia. Assessment of the type and concentration of mine sulfide dust in the underground mine atmosphere is vitally important for solving this problem. In practice, ores even with a sulfur content of less than 35% can constitute a sulfide dust explosion hazard, although mine dust with a sulfur content of less than 35% does not explode in laboratory conditions. To identify the cause of this phenomenon and develop technical solutions for ensuring safety of underground mining operations, change in the sulfur content of various mine dust fractions obtained from primary disintegration of sulfides was studied.

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Vasil’ev, N. V., S. N. Vavilov, and Yu A. Zeigarnik. "Visualization of the Processes Occurring during Spontaneous Triggering of a Vapor Explosion." Scientific Visualization 15, no. 2 (June 2023): 38–44. http://dx.doi.org/10.26583/sv.15.2.04.

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The vapor explosion process is an explosive increase in the volume of vapor, accompanied by a sharp rise in pressure when a hot melt enters a cold liquid medium with a temperature above its limiting superheat temperature. This phenomenon incurs the threat of great destruction and human casualties in certain types of accidents in the nuclear, metallurgical, pulp and paper industries. Nevertheless, there are still many insufficiently studied aspects of this phenomenon, one of which is the initiation (triggering) of the process. There are a number of logically fairly consistent descriptions of the processes occurring at a given stage of a vapor explosion. However, almost all of them are based on experiments carried out with external (forced) triggering. The article describes the data obtained during spontaneous triggering, i.e. under conditions much closer to reality. In this paper, using high-speed video recording (with a frame rate of up to 180 kHz and an exposure time of up to 2 μs), the first visualization of the processes occurring during spontaneous triggering of a vapor explosion on molten NaCl salt drops in distilled water subcooled to saturation temperature is presented. It is shown that when several drops of the NaCl melt interact with water, the micro vapor explosion that occurred on one drop, with an interval of several tens of microseconds, causes explosive vaporization on neighboring drops as well. Thus, the logical descriptions of the processes received instrumental confirmation.

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Tomescu, Cristian, Doru Cioclea, Emeric Chiuzan, Adrian Matei, and Răzvan Dragoescu. "Research on the phenomenon of explosive gas occurrence in drills for an engineering building-Case study -." MATEC Web of Conferences 290 (2019): 12028. http://dx.doi.org/10.1051/matecconf/201929012028.

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The security status indicator in a work system is characterized by safety levels or by risk levels. One of the types of risks in the workplace is the risk of explosion that is part of the risk factors specific to the working environment - chemical risk factors. The works of consolidating and arranging the infrastructure of a motorway include in their scheme the execution of a series of vertical geotechnical drills of the rock stratigraphic column on which is placed the construction and drillings dimensioned at certain depths and diameters which are concreted in order to ensure the load of the upper structure of the building. In some of these drills there has been a phenomenon of occurrence of gases that, within certain concentration limits, are explosive and create a state of danger by producing an explosion inside them, which by propagating to the surface can affect the safety of workers and means for work. This paper is a case study at a workplace of a trading company specializing in construction and proposes an analysis of the causes of explosive gases occurrence, work environment monitoring, and solutions for diminishing the OHS risk factors.

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Aleshin, G. Ya. "New working hypothesis of the ‘steam-explosion’ phenomenon." International Communications in Heat and Mass Transfer 24, no. 4 (July 1997): 497–505. http://dx.doi.org/10.1016/s0735-1933(97)00035-3.

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Florescu, Virgil, Laurențiu Rece, Ștefan Mocanu, and Amelitta Legendi. "Comparative Study on the Applicability of Analytical and Experimental Methods in the Analysis of the Safe Use of Rail Tankers Carrying Petroleum Products Under Pressure." Romanian Journal of Transport Infrastructure 7, no. 1 (July 1, 2018): 107–16. http://dx.doi.org/10.2478/rjti-2018-0007.

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Abstract The safety of railways has been and remains a critical topic. Whether it is infrastructure or rolling stock, the issue of safety is a permanent concern of the utmost importance, being reflected in the efficiency of any transport system. This paper focuses on the safety in operation of pressure vessels that equip railway tanks. There are many articles and works on this subject, and it is well-known that there are both national and international regulations regarding their design, execution, operation and maintenance. Also, there are quite a few reports on the BLEVE (Boiling Liquid Expanding Vapour Explosion) phenomenon resulting in material damage and significant casualties. The BLEVE-type explosion is not considered a chemical explosion derived from a gas-air explosive environment (also present in non-flammable gases), but rather a mechanical explosion through over-pressurization. Thus, we propose a comparative study between the results obtained using theoretical methods and those obtained as a result of tensoresistive measurements on such a tanker.

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Takeda, Daisuke, Woo Kyung Kim, Yukari Wada, Kazunori Kuwana, Toshio Mogi, and Ritsu Dobashi. "Toward Risk Assessment of Explosion Hazard: Experimental Determination of Flame Fractal Dimension." Advanced Materials Research 320 (August 2011): 151–55. http://dx.doi.org/10.4028/www.scientific.net/amr.320.151.

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Quantitative risk analysis is a method to evaluate risk and to identify areas for risk reduction. The final goal of our study is to propose an effective method for risk assessment of explosion hazard. To achieve the goal, a phenomenon that influences the consequences of explosion is first identified: self-turbulization and resulting acceleration of expanding flame during explosion. The fractal dimension is then identified as the key parameter that characterizes the phenomenon. Since the previous method to determine fractal dimension relies on large-scale explosion experiment, it has not been easy to determine fractal dimension. This paper demonstrates the possibility of determining fractal dimension by analyzing flame images of small-scale experiment, which might significantly reduce the cost of risk assessment of explosion hazard.

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Florea, Gheorghe Daniel, Emilian Ghicioi, Nicolae Ioan Vlasin, and Zoltan Vass. "Release of overpressures in computational simulations of air-methane explosions." MATEC Web of Conferences 373 (2022): 00043. http://dx.doi.org/10.1051/matecconf/202237300043.

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Research in the field of gas explosions has had and continues to have, as its main support, physical experiments performed on various scale models, the construction of real size models are often large consuming materials, time and labor. The rapid development of computing techniques has allowed among other things, the transfer of gas explosions research in the virtual space, for the validation of computational simulations of this type being still considered physical experiments and specialty literature. Within NIRD INSEMEX Petrosani, being an accredited institute in the elaboration of technical reports for gas explosion type events, the phenomenon of rapid combustion virtualization increased in time and as a result, computational simulations becoming an efficient tools in explaining the mechanisms of explosion production. Nevertheless, one of the problems raised by this virtualization process is the limitation of performing computational simulations in closed or partially closed spaces, initial conditions imposed, without the possibility of dynamic modification of these conditions according to the development of overpressures generated by the virtual explosion. This paper presents a computational experiment in which it was possible to transform the boundary conditions at predefined pressure thresholds, from rigid surfaces into surfaces capable of releasing the overpressures developed in closed / partially closed spaces, putting the results of this kind of simulations in line with real dynamic effects of gas explosion events.

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Li, Xiangcheng, Yuliang Lin, and Fangyun Lu. "Numerical Simulation on In-plane Deformation Characteristics of Lightweight Aluminum Honeycomb under Direct and Indirect Explosion." Materials 12, no. 14 (July 10, 2019): 2222. http://dx.doi.org/10.3390/ma12142222.

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Lightweight aluminum honeycomb is a buffering and energy-absorbed structure against dynamic impact and explosion. Direct and indirect explosions with different equivalent explosive masses are applied to investigate the in-plane deformation characteristics and energy-absorbing distribution of aluminum honeycombs. Two finite element models of honeycombs, i.e., rigid plate-honeycomb-rigid plate (RP-H-RP) and honeycomb-rigid plate (H-RP) are created. The models indicate that there are three deformation modes in the X1 direction for the RP-H-RP, which are the overall response mode at low equivalent explosive masses, transitional response mode at medium equivalent explosive masses, and local response mode at large equivalent explosive masses, respectively. Meanwhile, the honeycombs exhibit two deformation modes in the X2 direction, i.e., the expansion mode at low equivalent explosive masses and local inner concave mode at large equivalent explosive masses, respectively. Interestingly, a counter-intuitive phenomenon is observed on the loaded boundary of the H-RP. Besides, the energy distribution and buffering capacity of different parts on the honeycomb models are discussed. In a unit cell, most of the energy is absorbed by the edges with an edge thickness of 0.04 mm while little energy is absorbed by the other bilateral edges. For the buffering capacity, the honeycomb in the X1 direction behaves better than that in the X2 direction.

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Lv, Shu Ran, Qing Nan Wei, and Kai Yang. "Explosion Experimental Study Based on the Small Tailings Pond Model." Advanced Materials Research 919-921 (April 2014): 485–90. http://dx.doi.org/10.4028/www.scientific.net/amr.919-921.485.

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Explosion experiment was implemented on the small tailings dam model, aims to study the explosion effect of tailings sand under the action of the explosion. Explosion experiment includes three phases; experimental points were set respectively in the starter dam, embankment and deposited beach. In this experiment, blasting vibration velocity and vertical displacement of sand body are measured and collected, so did the tailings sand’s moisture content, cracks’ size, blasting crater, water and sand spurt phenomenon. Experimental results show that the buried conditions and tailings dam’s moisture content have a significant impact on explosion effect. By processing the velocity and displacement data, the attenuation law of blast vibration velocity in the tailings dam is reached, the blasting vibration velocity corresponding to crack damage of sand body is predicted, and the relationship between failure phenomenon of the tailings dam and the displacement produced by explosion is obtained.

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Xu, Chengjun, Chao Xu, Zhe Wei, and Fangzhi Cheng. "A Method to Locate Firing Points by Fusing Double CCD and GIS." Frontiers in Science and Engineering 3, no. 4 (April 20, 2023): 32–41. http://dx.doi.org/10.54691/fse.v3i4.4785.

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The precise positioning of the firing explosion point is an effective means to test the technical performance of artillery weapons and equipment warfare, but when the CCD single pole distance method is directly used to detect the explosion point, it is often affected by the obstacles in the shooting visual area, terrain and landform, and the detection and positioning accuracy is difficult to meet the evaluation requirements. To this end, the double CCD intersection method is first used to locate the explosive point, and the target recognition and positioning algorithm is used to realize the visual explosion point positioning, but this method also has the phenomenon of missing detection of the bomb point and ricochet explosion point. Then, the sensor is used to collect GIS signals at the point of explosion, which can well detect the location of missed bounces and ricochets, but there is also the cost of time registration and spatial coordinate system registration. In order to give full play to the complementary advantages of the two positioning methods, this paper proposes to establish a fusion localization model. Experiments have verified that the fusion positioning method improves the accuracy of the detection of the explosion point of traditional single live shooting, and can provide a reference for the positioning detection of related points of interest.

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Xie, Zui Wei, Xin Yue Wu, and Qiang Wan. "Relation between Actual Mass and Simulation Mass of Far-Field Underwater Explosion." Applied Mechanics and Materials 127 (October 2011): 350–54. http://dx.doi.org/10.4028/www.scientific.net/amm.127.350.

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The far-filed underwater explosive shock wave pressure and impulse is simulated by the FEM code LS-DYNA, and the simulation results are found having rapid decay characteristic through compared with the empirical results. Based on this phenomenon, the relations, whose validity is verified through a computation instance, between simulation mass and actual mass under given initial conditional is obtained by using curve fitting. Using those equations, the accuracy of LS-DYNA to simulate far-field underwater explosive can significantly be increased, thus the ability of this code to simulate far-field underwater explosion is enhanced.

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Yang, Yuezong, Zhushan Shao, Junfeng Mi, and Xiaofeng Xiong. "Effect of Adjacent Hole on the Blast-Induced Stress Concentration in Rock Blasting." Advances in Civil Engineering 2018 (November 15, 2018): 1–13. http://dx.doi.org/10.1155/2018/5172878.

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To investigate the effect of an adjacent hole on the blast-induced stress concentration in rock blasting, a rock blasting model with an adjacent hole is explored through theoretical analysis and numerical simulation. The commercial software LS-DYNA is utilized to simulate adjacent hole effect in rock blasting, in which the Johnson–Holmquist concrete material model is used to simulate rock and the high-explosive-burn-explosive and the equation of state of JWL are used to simulate explosive. Influences of the key parameters of adjacent hole effect in rock blasting, pitch of holes, adjacent hole diameter, and uncoupled medium in a blasting hole are extensively explored. According to the simulation results, when the explosion stress wave spreads to the adjacent hole wall, the tangential stress on the adjacent hole wall induced by the explosion stress wave is always greater than the radial stress. Adjacent hole diameter has a major effect on stress concentration, but with the adjacent hole diameter increasing, the stress concentration phenomenon weakens and the free surface effect of the adjacent hole plays a more important role.

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Cui, Yuanbo, Deren Kong, Jian Jiang, and Shang Gao. "Research on Electromagnetic Radiation Characteristics of Energetic Materials." Magnetochemistry 8, no. 5 (May 20, 2022): 57. http://dx.doi.org/10.3390/magnetochemistry8050057.

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During the explosion of energetic materials, electromagnetic interference is generated, which can affect the normal operation of surrounding electronic equipment. Therefore, an electromagnetic radiation measurement device based on a short-wave omnidirectional antenna and ultra-wideband omnidirectional antenna was designed to measure the electromagnetic radiation generated by the explosion of energetic materials of different masses, and the electromagnetic radiation characteristics were obtained through data processing. The results showed that the electromagnetic signal can still be collected hundreds of milliseconds after the explosive is detonated, and the electromagnetic radiation generated by the explosion is continuous and intermittent, which is a phenomenon that has not been found in this field at present. The mass of the energetic material had a significant effect on the time-domain characteristics of the electromagnetic radiation generated by the explosion: the higher the mass of the energetic material was, the shorter the delay response of the electromagnetic signal was, the longer the duration was, and the earlier the peak appeared. The frequency of electromagnetic radiation signals generated by the explosion of energetic materials was mainly concentrated below 100 MHz, and the energy was most concentrated in the frequency band of 0~50 MHz. The composition of energetic materials had the greatest influence on the spectral distribution, and the spectral distribution of electromagnetic radiation produced by the explosion of explosives with different compositions had obvious specificity. The electromagnetic radiation intensity generated by the explosion of energetic materials had a strong correlation with the distance from the explosion center, and it significantly decreased as the distance increased. The structure and detonation method of energetic materials changed the geometrical motion pattern during the explosion, resulting in the non-uniformity of electromagnetic radiation propagation.

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Lidner, Michał, and Zbigniew Szcześniak. "Simplified Numerical Modelling of a Blast Load Impact." Applied Mechanics and Materials 797 (November 2015): 131–36. http://dx.doi.org/10.4028/www.scientific.net/amm.797.131.

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Due to a particular complexity of the phenomenon of an explosion in a gaseous medium (air) the most appropriate approach to address it is using numerical methods. This paper presents a specific numerical solution to the phenomenon of the so-called point charge explosion from a one-dimensional perspective taking into account reflections from non-deformable partitions. Results of the numerical calculations were calibrated based on test results and their correctness was additionally verified using gas dynamics methods.

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Yuan, Xinjing, and Jian Song. "Numerical study of RC slabs under two-point contact explosion load." Journal of Physics: Conference Series 2215, no. 1 (February 1, 2022): 012014. http://dx.doi.org/10.1088/1742-6596/2215/1/012014.

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Abstract As an important bearing component of bridge, bridge deck is the key to bridge passage. In this paper, a solid model of reinforced concrete slab is established in LS-DYNA software, and the parameters are designed as the amount of explosive and the distance between explosives. The numerical simulation of two-point explosion test is carried out, and the damage mechanism and dynamic response of reinforced concrete slab under two-point explosion load are proposed. The results show that there is a phenomenon of energy accumulation in two-point contact explosion. At the same charge, the failure characteristics and dynamic response of RC slabs are related to the distance between the blast points. When the distance is small (30cm), the stress wave encounters and superposition strengthens between the blast points. When the spacing is large (60cm), the stress waves do not meet between the burst points, but reach the back burst surface and the side of the plate at the same time, and the damage is serious near the side of the plate, and the peak acceleration is small.

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Davis, Scott, Derek Engel, Kees van Wingerden, and Erik Merilo. "Can gases behave like explosives: Large-scale deflagration to detonation testing." Journal of Fire Sciences 35, no. 5 (September 2017): 434–54. http://dx.doi.org/10.1177/0734904117715648.

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A large vapor cloud explosion followed by a fire is one of the most dangerous and high consequence events that can occur at petrochemical facilities. However, one of the most devastating explosions is when a deflagration transitions to a detonation, which can travel at speeds greater than 1800 m/s and pressures greater than 18 barg. This phenomenon is called a deflagration-to-detonation transition, whereby the deflagration (flame front) continues to accelerate due to confinement or flow-induced turbulence (e.g. obstacles) and ultimately transitions at flame speeds greater than the speed of sound to a detonation. Unlike a deflagration that requires the presence of confinement or obstacles to generate high flame speeds and associated elevated overpressures, a detonation is a self-sustaining phenomenon having the shock front coupled to the combustion. Once established, the resulting detonation will continue to propagate through the vapor cloud at speeds (1800 m/s) that are of similar order as high explosives (7000–8000 m/s). While there are differences between high explosives and vapor cloud explosions (e.g. high explosives can have pressures well in excess of 100 bar), vapor cloud explosions that transition to detonations can cause significant damage due to the extremely high pressures not typically associated with gas phase explosions (>18 barg), high energy release rate per unit mass, and higher impulses due to large cloud sizes. While the likelihood of deflagration-to-detonation transitions is lower than deflagrations, they have been identified in some of the most recent large-scale explosion incidents. The consequences of deflagration-to-detonation transitions can be orders of magnitude larger than deflagrations. This article will present the results of large-scale testing conducted in a newly developed test rig of 1500 m3 gross volume involving stoichiometric, lean, and rich mixtures of propane and methane.

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Barnat, W. "Validation of the pressure wave model in the aspect of special structures endurance." Bulletin of the Polish Academy of Sciences Technical Sciences 63, no. 3 (September 1, 2015): 707–16. http://dx.doi.org/10.1515/bpasts-2015-0082.

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Abstract The article presents results of the research on the validation of impact wave in the aspect of special structures’ endurance. Impact waves have been examined according to numerical and analytical methods. In order to verify the results obtained, a workstation for experimental research had been prepared. Before conducting the experiment, approximate pressure value had been checked empirically. The pressure had been measured using sensors for free wave measurements. The topic of the paper is empirical examination of the phenomenon of explosion in the aspect of the free wave pressure. Due to a difficulty of the issue, it was necessary to conduct complex examination of the phenomenon for various charges. The paper examines cases of spherical charge explosions with a balanced mass of 1 kg TNT.

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Ji, Long, Ping Wang, Youer Cai, Wei Shang, and Xudong Zu. "Blast Resistance of 240 mm Building Wall Coated with Polyurea Elastomer." Materials 15, no. 3 (January 23, 2022): 850. http://dx.doi.org/10.3390/ma15030850.

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Enhancing the blast resistance of building walls is a research hotspot in the field of anti-terrorism and explosion protection. In this study, numerical simulation and experimental verification were combined to analyze the failure phenomenon of brick masonry wall and sprayed polyurea-reinforced brick wall under contact explosion and determine the failure response parameters of the wall. The failure limit, mode, and mechanism of a 240 mm wall without reinforcement and strengthened with polyurea elastomer under different strength loads were investigated. Under contact explosion, the increase in the size of the blasting pit of the 240 mm wall gradually slowed down after the dose was increased to higher than 0.5 kg. Thereafter, the energy of the explosive load was released by splashing wall fragments as well as by deflecting and movement of the wall. The results show that the 240 mm walls sprayed with polyurea elastomer had outstanding anti-explosion performance because it wraps the damaged area and fragments of masonry wall inside the polyurea layer. When the thickness of the polyurea layer increases to 8 mm, the damaged area of the masonry wall decreases by 55.6% compared with that without reinforcement. The numerical simulation results were in good agreement with the experimental results.

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Hadavi, V., J. Zamani Ashani, and A. Mozaffari. "Theoretical calculation of the maximum radial deformation of a cylindrical shell under explosive forming by a new energy approach." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 3 (August 15, 2011): 576–84. http://dx.doi.org/10.1177/0954406211416190.

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Due to different influential parameters that affect an explosive forming process, this classic method of metal forming can potentially be considered as one the most complicated practical approaches to forming metallic shells and plates. Focusing on the importance of the energetic efficiency during an explosive forming procedure, the explosion phenomenon and relating formulation will be reviewed in this article. Furthermore, influential differences between air and water as the media of explosion and their effects on explosive forming process will be discussed. On the other hand, a new theory, called ‘the energy method’ that can be used for calculation of the maximum radial deflection of cylindrical shells under explosive loading will be introduced in this article. Besides, the selected results of hundreds of experiments that have been conducted on different tubular shells by the use of water and air as media of explosive forming process will be presented and the maximum transverse displacements of the shells that have been experimentally tested will then be compared to the results of the proposed energy method. Comparison between the maximum radial deformation of cylindrical specimens that were used in this research and theoretical results shows that the accuracy of the new theory is approximately 84%.

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Min, B. T., S. W. Hong, J. H. Kim, I. K. Park, and H. D. Kim. "Dominant Factor for the Occurrence of a Steam Explosion." Defect and Diffusion Forum 273-276 (February 2008): 388–93. http://dx.doi.org/10.4028/www.scientific.net/ddf.273-276.388.

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For the study of a steam explosion phenomenon in a nuclear reactor, prototypic corium, a mixture of UO2 and ZrO2 was melted in a cold crucible by applying an induction heating technique. The molten corium was then poured into cold water. It was fragmented into very small particles, so called debris, which enables a very rapid heat transfer to the water. Some cases led to steam explosions by thermal expansion of the water. After the tests, all the debris particles were dried and classified by their size. From the analysis by using EPMA, it was shown that the particles generated by a steam explosion had fine and irregular forms. It is known that real corium (including UO2) hardly leads to a steam explosion, different from pure ZrO2 or metal. A reason for this was previously suggested in that the corium generated hydrogen gas during melt-water interaction, and it enclosed the melt drops to prevent a direct contact of the corium and water. In order to confirm this fact, the debris particles were analyzed with ICP-AES for their typical element contents, EPMA for the homogeneity of the solid solution, XRD for the chemical compounds, and TGA and hydrogen reduction analysis for the percentage of the debris oxidation and reduction. These analyses showed that hydrogen was not directly related to steam explosion. Meanwhile, the material characteristics of the corium compositions are newly suggested to be the most probable reason for the occurrence of a steam explosion so far.

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Rădoi, Florin, Ion Gherghe, and Alexandru Cămărășescu. "Experimental possibilities for industrial ventilation." MATEC Web of Conferences 354 (2022): 00030. http://dx.doi.org/10.1051/matecconf/202235400030.

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The activity of evaluation and verification of industrial ventilation installations has a strong preventive role in terms of explosion risk mainly due to the fact that of the three determining elements that can lead to an explosion phenomenon, ventilation installations can determine the presence of two elements namely the presence of fuel (gases, vapours, dusts, mists) and the source of initiation (hot surface, flame, sparks of mechanical origin, electrical sparks, static electricity, etc.). The development of experimental systems on„ which particular hazardous aspects that may occur during the operation of industrial ventilation systems can be studied are vital to avoid dangerous situations in the current operation of ventilation installations. Knowledge of the dynamics of formation of explosive / toxic / asphyxiating environments is achieved by analysing explosive mixtures in relation to specific explosive intervals and is one of the most important priorities in ensuring optimal health and safety at work in industrial activities. The information obtained by analysing the dynamics of the formation of explosive / toxic / asphyxiating atmospheres is extremely useful for personnel responsible for health and safety at work, because with their help relevant decisions can be made to ensure safety and health conditions at the level of industrial premises. The paper presents an experimental equipment usable for the study of industrial ventilation systems.

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Lunn, Geoff, and Sarah Colwell. "The first world seminar on the explosion phenomenon and on the application of explosion protection techniques in practice." Journal of Loss Prevention in the Process Industries 6, no. 2 (March 1993): 133–34. http://dx.doi.org/10.1016/0950-4230(93)90010-u.

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Wang, Dong, Yang Du, Xin Sheng Jiang, Jian Jun Liang, and Jian Zhong Zhou. "Experimental Study on Dispersion and Explosion Process of Fuel-Air Mixture in Underground Fuel Depot." Applied Mechanics and Materials 590 (June 2014): 261–65. http://dx.doi.org/10.4028/www.scientific.net/amm.590.261.

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In this paper, the fuel-air dispersion and explosion experimental system was designed and experimental simulation on fuel-air mixture spreading and exploding in long-narrow underground fuel depot was carried out. The special phenomena of fuel-air mixture dispersion and explosion process, the characteristic feature of the pressure curve and mechanism were analyzed. The explosion process can be divided into three stages: flame accelerating section, oscillating reaction section and wave dissipating section. And under the same initial conditions, if the ignition time advanced, there is a significant intermittent and large fluctuations phenomenon.

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Yu, Jun, Wen-Wei Wu, Bo Yan, Jiu-Ting Dong, and Xian-Pi Zhang. "Study on the mechanism and load characteristics of secondary cavitation near free surface in underwater explosion." AIP Advances 12, no. 10 (October 1, 2022): 105222. http://dx.doi.org/10.1063/5.0121834.

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Although the cavitation phenomenon in underwater explosion has been researched for more than 100 years, the phase transition models based on mass and heat exchange between liquid and its vapor phases have only been established in the past decade. In this study, the secondary cavitation phenomenon was first captured by phase transition based on a four-equation system. The bulk cavitation near the free surface induced by underwater explosion was numerically investigated, and three typical bulk cavitation cases were investigated to explore their motion mechanisms and load characteristics on hydrodynamics and phase transition generation. It was found that secondary bulk cavitation will occur only under the condition that both the initial shock wave intensity and the distance between the water surface and the explosion bubble are satisfied in a specific relationship. Producing bulk cavitation was difficult at a relatively deep detonation depth because of the weak rarefaction wave reflected from the water surface by smaller charges. The statistical data under the condition of small charge indicated that the duration of cavitation increases with the increase in charge weight but the growth trend slows down gradually. However, the maximum volume of cavitation increased linearly with an increase in the charge weight. The present results can expand the currently limited database of underwater explosion multiphase fluids and provide insight into the interactions between the shock wave, bulk cavitation, explosion bubble, and water surface.

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Fowler, A. C., Bettina Scheu, W. T. Lee, and M. J. McGuinness. "A theoretical model of the explosive fragmentation of vesicular magma." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 466, no. 2115 (November 3, 2009): 731–52. http://dx.doi.org/10.1098/rspa.2009.0382.

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Recent experimental work has shown that, when a vertical column of rock under large pressure is suddenly depressurized, the column can ‘explode’ in a structured and repeatable way. The observations show that a sequence of horizontal fractures forms from the top down, and the resulting blocks are lifted off and ejected. The blocks can suffer secondary internal fractures. This experiment provides a framework for understanding the way in which catastrophic explosion can occur, and is motivated by the corresponding phenomenon of magmatic explosion during Vulcanian eruptions. We build a theoretical model to describe these results, and show that it is capable of describing both the primary sequence of fracturing and the secondary intrablock fracturing. The model allows us to suggest a practical criterion for when such explosions occur: firstly, the initial confining pressure must exceed the yield stress of the rock, and, secondly, the diffusion of the gas by porous flow must be sufficiently slow that a large excess pore pressure is built up. This will be the case if the rock permeability is small enough.

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Zhu, Shan Shan, Cheng Juan Wang, and Huan Song Yang. "Practice and Explosion of Pupils’ Writing Estimation Based on Tablets." Advanced Materials Research 971-973 (June 2014): 2595–98. http://dx.doi.org/10.4028/www.scientific.net/amr.971-973.2595.

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The estimation of writing is often omitted by students and teachers in the real writing teaching, this phenomenon may seriously influence the improvement of teaching level in pupil’s writing. Focus on this phenomenon, I have obtained 4 strategies based on tablets to estimate pupil’s writing through the platform of tablets,which realizes the interaction between person and machine, communication among students and with teachers. Therefore, these strategies can change the conservative ways of teaching and arouse students’ interest for writing sentences and compositions , which makes full preparation for the writing training of next step.

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Mandal, Jagriti, ManmohanDass Goel, and AjayKumar Agarwal. "Effect of Horizontal Curve on the Response of Road Tunnels under Internal Explosion." Proceedings of the 12th Structural Engineering Convention, SEC 2022: Themes 1-2 1, no. 1 (December 19, 2022): 1293–97. http://dx.doi.org/10.38208/acp.v1.653.

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Internal explosion in a tunnel is a complex loading phenomenon where the tunnel lining is subjected to not only direct impact of explosion but also loading due to multiple reflection of blast waves which could be of magnitude higher than that of incident blast wave. This kind of loading is complex in nature and difficult to predict using simple analysis tools. Further, it poses a serious threat to its structural integrity. Studies have been conducted in the past to understand the behaviour of tunnel under internal explosion. However, they have been focused on straight tunnels ignoring the convex and concave shapes introduced due to horizontal and vertical curves. Shape of the target surface has significant effect on the characteristics of blast wave. This study investigates the effect of horizontal curves on the damage behaviour of tunnel lining due to internal explosion. A series of numerical simulation are performed on box-shaped tunnel with varying curvature radius and the results are compared with that of straight tunnel adopting Multi-Material Arbitrary Lagrangian-Eulerian (MM-ALE) method using LS-DYNA®. Explosive and air are modeled using ALE formulation, whereas, tunnel and soil are modeled using Lagrangian formulation. Further, Jones-Wilkins-Lee equation of state is used to model the explosion. Damage to the tunnel lining is measured in terms of peak particle velocity (PPV) and von-Mises stress. It is observed that walls of curved tunnels undergo more PPV compared with straight tunnel wherein concave wall show the highest PPV. Propagation of blast wave along the tunnel length is significantly affected due to the introduction of curvature resulting in change in reflection patterns. This further leads to variation in stress contours on tunnel lining with higher concentration of stress in curved tunnels than in straight tunnel.

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Gabel, Jason. "Tall trends: quantifying the skyscraper phenomenon." E3S Web of Conferences 33 (2018): 01012. http://dx.doi.org/10.1051/e3sconf/20183301012.

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The world continues to witness an explosion of growth in the number of 200-plus-meter skyscrapers, with three straight years of record-breaking completions (from 2014 to 2016) and a 441 percent increase on the total number of such towers in the 21st century, from 265 in 2000 to 1,168 at the end of 2016. Fueled largely by strong economic performance, much of this activity is centered in Asia and the Middle East, upending longstanding geopolitical trends. China in particular has dominated worldwide skyscraper construction, accounting for two-thirds of all completions in the last calendar year (2016). Further, the traditional role of the skyscraper has diversified, with residential and mixed-use buildings accounting for a greater share of 200-plus-meter buildings. This paper explores these interconnected trends in detail and analyzes both the causes and impacts of an evolving skyscraper industry.

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Tomisaka, Kohji, and Satoru Ikeuchi. "Collective Effects of Supernova Explosions in a Starburst Nucleus." International Astronomical Union Colloquium 101 (1988): 477–80. http://dx.doi.org/10.1017/s0252921100102878.

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AbstractThe collective effects of supernova (SN) explosions in the nucleus of a starburst galaxy are studied. It is shown that a large wind bubble with the size of a few hundred parsecs in the nucleus of a starburst galaxy will expand for SN explosion rates of 0.1 per year or greater. The bubble gradually elongates due to density stratification. Finally, the shell breaks near the top and the hot matter flows through the cylindrical shell up to 1-2 kpc above the disk plane. We will discuss the X-ray emission in the halos of galaxies such as M82 and NGC 253 and the distribution of molecular gas in such galaxies in relation to the starburst phenomenon.

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Dragoni, Michele, and Dalila Santoro. "A model for the atmospheric shock wave produced by a strong volcanic explosion." Geophysical Journal International 222, no. 2 (May 7, 2020): 735–42. http://dx.doi.org/10.1093/gji/ggaa205.

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SUMMARY Atmospheric shock waves are a common phenomenon in explosive volcanic eruptions. We consider the motion of a spherical shock wave generated by a point source in the strong shock approximation. The shock front corresponds to discontinuities in the gas velocity, density, pressure and temperature, which are calculated as functions of the energy of the explosion. The problem is solved analytically for the distributions of velocity, density, pressure and temperature in the atmosphere as functions of the distance from the source. The motion of the shock wave being supersonic, the solution is valid for a few seconds after the explosion, corresponding to a distance of few kilometres. The acoustic effect of the shock wave, expressed by the peak sound pressure level, is calculated and may reach hundreds of decibels. The pressure waveform that could be recorded in the vicinity of the volcano is calculated and compared with typical waveforms in weak shock conditions. The change in the refractive index of air due to density inhomogeneity is calculated and the conditions under which a condensation cloud is formed behind the shock front are investigated.

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Zhang, Peili, Jianxiang Li, Yanbo Guo, and Yang Du. "The secondary explosion phenomenon of gasoline-air mixture in a confined tunnel." IOP Conference Series: Earth and Environmental Science 64 (May 2017): 012008. http://dx.doi.org/10.1088/1755-1315/64/1/012008.

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Zhang, Kai, and Lu Qing Zhang. "Phenomenon of Gaseous Adiabatic Compression of Powder in Explosive Compaction." Materials Science Forum 816 (April 2015): 711–14. http://dx.doi.org/10.4028/www.scientific.net/msf.816.711.

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This paper introducesan explosion experiment, in which the powder can be recollected100%. Based on the observations inside the recollected powder case,it can be confirmed that the very small amount of air in the space within the powderis concentrated in the bottom of the powder case,and consequently results in adiabatic compression. The compression energy of air gives rise tothe extra high powder temperature. A theoretical approach to the adiabatic mechanism was discussed and a rough estimationwas provided onthe degree of the increased temperature.

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Egorova, Lidia A., and Valery V. Lokhin. "Modeling of Energy Release at the Final Stage of the Meteoroid Movement." Open Astronomy 27, no. 1 (August 1, 2016): 290–93. http://dx.doi.org/10.1515/astro-2018-0035.

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Abstract The paper continues to build upon the author’s previous research on fireballs fragmentation. A model of the sudden explosive destruction of the cosmic body at the height of the maximum flash is used. After the fragmentation, the kinetic energy of the moving particles of a meteoroid passes into the thermal energy of the gas volume inwhich their motion takes place. The temperature of a gas cloud calculated analytically using energy conservation lawand equations of physical theory of meteors. The mass distribution of fragments was taken from the literature. The high temperature of the gas in a cloud allows us to talk about the phenomenon of a "thermal explosion".

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Desroches, Mathieu, Emilio Freire, S. John Hogan, Enrique Ponce, and Phanikrishna Thota. "Canards in piecewise-linear systems: explosions and super-explosions." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 469, no. 2154 (June 8, 2013): 20120603. http://dx.doi.org/10.1098/rspa.2012.0603.

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We show that a planar slow–fast piecewise-linear (PWL) system with three zones admits limit cycles that share a lot of similarity with van der Pol canards, in particular an explosive growth. Using phase-space compactification, we show that these quasi-canard cycles are strongly related to a bifurcation at infinity. Furthermore, we investigate a limiting case in which we show the existence of a continuum of canard homoclinic connections that coexist for a single-parameter value and with amplitude ranging from an order of ε to an order of 1, a phenomenon truly associated with the non-smooth character of this system and which we call super-explosion .

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Sławiński, Grzegorz, and Tadeusz Niezgoda. "Protection of Occupants Military Vehicles Against Mine Threats and Improvised Explosive Devices (IED) / Ochrona Załogi Pojazdu Wojskowego Przed Wybuchem Min i Improwizowanych Urządzeń Wybuchowych (IED)." Journal of KONBiN 33, no. 1 (September 1, 2015): 113–22. http://dx.doi.org/10.1515/jok-2015-0009.

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Abstract Risk of danger for military vehicle crew life and health increases when explosion under vehicle appears. Consideration of this phenomenon in the aspect of soldiers safety is based on coupled analysis of soldier’s body, car seat and vehicle construction elements. As the effect of blast wave interaction the vibrations of construction and passanger body acceleration appear. In the paper the analysis of improvised explosive device (IED) detonation under the military vehicle was carried out in the aspect of soldier neck spine injury. The analysis was made with the usage of numerical methods in LS Dyna computer code and considered the changeble values of displacement and acceleration registered during detonation.

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Ma, Huayuan, Mingshou Zhong, Xinghua Li, Quanmin Xie, You Zhou, and Qin Yin. "Experimental and Numerical Simulation Study on the Shock and Vibration Effect of OD1422-X80 Mainline Natural Gas Pipeline Explosion." Shock and Vibration 2019 (May 26, 2019): 1–13. http://dx.doi.org/10.1155/2019/6824819.

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In this paper, the explosion experiment of the OD1422-X80 natural gas pipeline was carried out. The phenomenon of pipeline explosion was recorded, and a large amount of data on vibration effects were obtained. The data showed that the ground vibration during the explosion was mainly caused by the physical explosion process, and the subsequent gas explosion did not produce strong vibration. Based on the ANSYS/LS-DYNA platform, a numerical calculation model of this experiment was established. The numerical results agreed well with the experimental results. Simulation and experimental results showed that when the gas pressure in the pipe was lower than 7 MPa, the pipeline cracks stop growing. The maximum speed of the pipe wall moving outward reached 50 m/s, which formed a huge impact compression effect on the surrounding soil. This state spread to distant places and gradually decayed into an elastic stress wave, which formed a ground vibration effect. Time-frequency analysis was introduced into the vibration signal processing. The analysis results showed that the main frequency of pipeline explosion vibration was distributed around 10 Hz and had a long duration. The research results provided a reference for subsequent gas pipeline explosion test and numerical simulation research.

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Gorodilov, Yu N. "About the origin of the "Cambrian Explosion" phenomenon and on the origin of animal types." Proceedings of the Zoological Institute RAS 323, Supplement 7 (December 6, 2019): 1–125. http://dx.doi.org/10.31610/trudyzin/2019.supl.7.5.

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The term “Cambrian explosion” refers to the sudden appearance of a large number of new taxa of animals of higher rank (classes, types) on the geological scale, documented by the excavation of sedimentary strata belonging to the Cambrian period of geological time. For 150 years, this evolutionary phenomenon has remained unsolved from the standpoint of traditional Darwinism, nor from the standpoint of its later modifications – the Synthetic theory of evolution and the theory of discontinuous equilibrium. Up to now, creationism was regarded as the only alternative to solving this problem. The author of this work, analyzing the vast factual material presented by embryologists, zoologists, paleontologists, molecular biologists, including those obtained at the end of the 20th and beginning of the 21st centuries, offers a new natural-scientific concept to explain the causes for the explosion of macroevolutionary variability at the beginning of the Cambrian period.

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Gorodilov, Yu N. "About the origin of the "Cambrian Explosion" phenomenon and on the origin of animal types." Proceedings of the Zoological Institute RAS 323, Supplement 7 (December 6, 2019): 1–125. http://dx.doi.org/10.31610/trudyzin/2019.supl.9.5.

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The term “Cambrian explosion” refers to the sudden appearance of a large number of new taxa of animals of higher rank (classes, types) on the geological scale, documented by the excavation of sedimentary strata belonging to the Cambrian period of geological time. For 150 years, this evolutionary phenomenon has remained unsolved from the standpoint of traditional Darwinism, nor from the standpoint of its later modifications – the Synthetic theory of evolution and the theory of discontinuous equilibrium. Up to now, creationism was regarded as the only alternative to solving this problem. The author of this work, analyzing the vast factual material presented by embryologists, zoologists, paleontologists, molecular biologists, including those obtained at the end of the 20th and beginning of the 21st centuries, offers a new natural-scientific concept to explain the causes for the explosion of macroevolutionary variability at the beginning of the Cambrian period.

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Journal articles on the topic 'Explosion Phenomenon'

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