Journal articles: 'Air blast propagation'

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DENG, RONG-BING, and XIAN-LONG JIN. "THREE-DIMENSIONAL SIMULATION OF CONDENSED EXPLOSIVE-INDUCED FLOW PROPAGATION AND INTERACTION WITH GLASS CURTAIN WALL." Modern Physics Letters B 24, no. 09 (2010): 833–48. http://dx.doi.org/10.1142/s0217984910022895.

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In order to carry out blast response of curtain wall, the first step is to understand the complex flow of the air blasts around the structures and predict the blast loads acting on the structures. But in earlier studies related to blast resistant design of glass curtain wall, blast flow induced by condensed explosive is not taken into account due to expensively computational resources required. Based on high performance computing, this paper presents a new three-dimensional numerical simulation method of condensed explosive-induced flow propagation and impact on a complex glass curtain wall, where the fluid is represented by solving Navier–Stokes equations with a multimaterial arbitrary Lagrangian–Eulerian (ALE) formulation. In particular, the whole analytical model consists of condensed explosive, air, detailed curtain wall system, and ground, which comprehensively represents the real fluid–structure interaction environment. Final calculation has been performed on the Dawning 4000A supercomputer based on the domain decomposition method. The flow mechanisms of blast wave rounding curtain wall is visualized and the simulated pressure history of gauge is in good agreement with the experimental result which validates this method. The present method is shown to be a useful tool for blast resistance design of curtain wall in the future.

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Ashratov, �. A., U. G. Pirumov, and V. V. Surkov. "Blast wave propagation in air from a gaseous charge." Fluid Dynamics 21, no. 3 (1986): 431–37. http://dx.doi.org/10.1007/bf01409730.

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Liang, Minzu, Xiangyu Li, Yuliang Lin, and Fangyun Lu. "Compaction Wave Propagation in Layered Cellular Materials Under Air-Blast." International Journal of Applied Mechanics 11, no. 01 (2019): 1950003. http://dx.doi.org/10.1142/s1758825119500030.

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The propagation of compaction waves in layered cellular material subjected to air-blast is analyzed to examine the mechanism of compaction wave and reveal the phenomena that develop at the interface between the cellular layers. Similar to the previous studies of cellular materials under dynamic loading, the topology of cellular materials is neglected and homogeneous properties are assumed. The rigid-perfectly plastic-locking (R-PP-L) material idealization and the simple shock theory are employed to analyze the compaction situations. Analytical solutions for compaction wave propagation of double-layer cellular materials with two gradient-arrangements under air-blast loading have been worked out. The densification wave occurs at the blast end and then gradually propagates to the distal end for layers’ densities increase in the propagation direction (positive gradient). While compaction waves simultaneously form in both layers and propagate to the distal end in the same direction for the negative gradient. The finite element (FE) models using the Voronoi technique are carried out with practical aluminum foam to verify the predictions of the theoretical analysis. The potential of layered cellular materials to design efficient structural components under air-blast load is discussed, which would outperform their corresponding single counterpart with equal mass.

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Zhang, Xiu Hua, and Yan Yan Wu. "Numerical Analysis of Shock Wave Propagation Law of Internal Gas Explosion." Applied Mechanics and Materials 105-107 (September 2011): 299–302. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.299.

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The purpose of this paper is to research on shock wave propagation law of internal gas explosion. The multi-material Eulerian and Lagrangian coupling algorithm was adopt. Using ANSYS/LS-DYNA dynamic analysis software to build frame structure, air and gas explosion models. Multiple ALE elements for simulating air and gas explosion material the analysis of blast shock wave propagation in a three-story steel frame structure and the characteristics of explosion pressure using fluid-structure coupling method are carried out. The conclusions show that fluid-structure coupling method can well simulated shock wave propagation of internal gas explosion, and the pressure peak of blast shock wave increased with the increasing of the blast air initial energy. Locality is the characteristic of explosion pressure in sealed space, and the pressure pass weakly when it propagates in solid.

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Akhlaghi, Ebrahim. "Numerical Simulation of Air Shock Wave Propagation Effects in Reinforced Concrete Columns." Journal of Modeling and Optimization 12, no. 1 (2020): 12–22. http://dx.doi.org/10.32732/jmo.2020.12.1.12.

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Reinforced concrete has been shown to be a desirable material of choice in blast resistant structures due to its availability, relatively low cost, and its inherent ability to absorb energy produced by explosions. Most research work investigating the behaviour of reinforced concrete columns to blast loading have concentrated on their response to planar loading from far-field explosions. Limited amount of work is available on the effects of near-field explosion on the behaviour of reinforced concrete columns. This study is aimed to investigate effects of explosive loads on RC column by using ALE method. Commercial finite element package, LS-DYNA is used to simulate the behavior of blast wave on RC columns. Numerical simulation is validated against experimental work done in literature. The experience gained from this research provides valuable information for the development of the finite element modeling of real blast load effects on RC columns.

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Dharma Rao, Vedula, Adapaka Srinivas Kumar, Kadiyam Venkateswara Rao, and Veerapaneni S. R. Krishna Prasad. "Theoretical and Experimental Studies on Blast Wave Propagation in Air." Propellants, Explosives, Pyrotechnics 40, no. 1 (2014): 138–43. http://dx.doi.org/10.1002/prep.201400042.

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Bayle, P., M. Bayle, and G. Forn. "Blast wave propagation in glow to spark transition in air." Journal of Physics D: Applied Physics 18, no. 12 (1985): 2417–32. http://dx.doi.org/10.1088/0022-3727/18/12/011.

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Mazepa, E. E., P. I. Kusainov, A. Yu Krainov, and O. Yu Lukashov. "Modeling the propagation of air blast waves in mine workings." Journal of Physics: Conference Series 1749 (January 2021): 012041. http://dx.doi.org/10.1088/1742-6596/1749/1/012041.

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Draganić, Hrvoje, and Damir Varevac. "Analysis of Blast Wave Parameters Depending on Air Mesh Size." Shock and Vibration 2018 (July 8, 2018): 1–18. http://dx.doi.org/10.1155/2018/3157457.

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Results of numerical simulations of explosion events greatly depend on the mesh size. Since these simulations demand large amounts of processing time, it is necessary to identify an optimal mesh size that will speed up the calculation and give adequate results. To obtain optimal mesh sizes for further large-scale numerical simulations of blast wave interactions with overpasses, mesh size convergence tests were conducted for incident and reflected blast waves for close range bursts (up to 5 m). Ansys Autodyn hydrocode software was used for blast modelling in axisymmetric environment for incident pressures and in a 3D environment for reflected pressures. In the axisymmetric environment only the blast wave propagation through the air was considered, and in 3D environment blast wave interaction and reflection of a rigid surface were considered. Analysis showed that numerical results greatly depend on the mesh size and Richardson extrapolation was used for extrapolating optimal mesh size for considered blast scenarios.

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Sembian, S., M. Liverts, and N. Apazidis. "Plane blast wave propagation in air with a transverse thermal inhomogeneity." European Journal of Mechanics - B/Fluids 67 (January 2018): 220–30. http://dx.doi.org/10.1016/j.euromechflu.2017.09.011.

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Zhang, Gang. "Experimental Study on Shock Wave Propagation of the Explosion in a Pipe with Holes by High-Speed Schlieren Method." Shock and Vibration 2020 (September 12, 2020): 1–9. http://dx.doi.org/10.1155/2020/8850443.

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The shock wave propagation of the explosion in a pipe with holes was studied by a high-speed schlieren experimental system. In the experiments, schlieren images in the explosion were recorded by a high-speed camera from parallel and perpendicular orientations, respectively, and the pressure in the air was measured by an overpressure test system. In parallel orientation, it is observed that the steel pipe blocks the propagation of blast gases, but it allows the propagation of shock waves with a symmetrical shape. In perpendicular orientation, oblique shock wave fronts were observed, indicating the propagation of explosion detonation along the charge. Shock wave velocity in the hole direction is larger than that in the nonhole direction, indicating the function of holes in controlling blast energy, that is, leading blast energy to hole direction. Furthermore, the function of holes is verified by overpressure measurements in which peak overpressure in the hole direction is 0.87 KPa, 2.8 times larger than that in the nonhole direction. Finally, the variation of pressure around the explosion in a pipe with holes was analyzed by numerical simulation, qualitatively agreeing with high-speed schlieren experiments.

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Mogi, Toshio, Tomoyuki Matsunaga, and Ritsu Dobashi. "Propagation of blast waves from a bursting vessel with internal hydrogen-air deflagration." International Journal of Hydrogen Energy 42, no. 11 (2017): 7683–90. http://dx.doi.org/10.1016/j.ijhydene.2016.06.106.

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Ma, Qiuju, Qi Zhang, and Jiachen Chen. "Numerical analysis on propagation characteristics of methane/air explosion in elbow pipe and pipe network." International Journal of Numerical Methods for Heat & Fluid Flow 24, no. 7 (2014): 1610–23. http://dx.doi.org/10.1108/hff-06-2013-0191.

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Purpose – The purpose of this paper is to study propagation characteristics of methane explosion in the pipe network and analyze the propagation laws of methane explosion wave along the elbow pipe and pipe network. Design/methodology/approach – Numerical simulation using software package AutoReaGas, a finite-volume computational code for fluid dynamics suitable for gas explosion and blast problems, is adopted to simulate the propagation characteristics of methane explosion and the property of flow field in complex structures. Findings – Due to reflection effects of corners of elbow pipe, the peak overpressures at corner locations in the elbow pipe go about two times higher than that in the straight pipe. In the parallel pipe network, the peak overpressure increases significantly at the intersection point, while the flame speed decreases at the junction. All these indicate that pipe corners and bifurcations could substantially enhance explosion partly which can bring more severe damage at the corner area. The explosion violence is strengthened after flames and blast waves are superimposed, such that equipments and people in these areas need special strengthening protection. Originality/value – The numerical results presented in this paper may provide some useful guidance for the design of the underground laneway structures and to take protective measures at corners and bifurcations in coal mines.

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Pathak, Shashank, and G. V. Ramana. "A Designer’s Approach for Estimation of Nuclear-Air-Blast-Induced Ground Motion." Advances in Civil Engineering 2018 (2018): 1–12. http://dx.doi.org/10.1155/2018/3029837.

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A reliable estimate of free-field ground displacement induced by nuclear-air-blast is required for design of underground strategic structures. A generalized pseudostatic formulation is proposed to estimate nuclear-air-blast-induced ground displacement that takes into account nonlinear stress-strain behaviour of geomaterials, stress-dependent wave propagation velocity, and stress wave attenuation. This proposed formulation is utilized to develop a closed-form solution for linearly decaying blast load applied on a layered ground medium with bilinear hysteretic behaviour. Parametric studies of closed-form solution indicated that selection of appropriate constrained modulus consistent with the overpressure is necessary for an accurate estimation of peak ground displacement. Stress wave attenuation affects the computed displacement under low overpressure, and stress-dependent wave velocity affects mainly the occurrence time of peak displacement and not its magnitude. Further, peak displacements are estimated using the proposed model as well as the UFC manual and compared against the field data of atmospheric nuclear test carried out at Nevada test site. It is found that the proposed model is in good agreement with field data, whereas the UFC manual significantly underestimates the peak ground displacements under higher overpressures.

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Fang, Yong, Yi-Lun Zou, Jian Zhou, Zhi-gang Yao, Shuai Lei, and Wenbo Yang. "Field Tests on the Attenuation Characteristics of the Blast Air Waves in a Long Road Tunnel: A Case Study." Shock and Vibration 2019 (April 24, 2019): 1–11. http://dx.doi.org/10.1155/2019/9693524.

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After an explosion occurs in a tunnel, the blast waves take on diverse forms of attenuation in different regions when it propagates along the tunnel. However, the prediction of the overpressure decay laws proposed in previous studies has not taken into account the influence of the different regions in the tunnel. The present paper uses the example of the Micangshan highway tunnel in China and considers many factors that influence the propagation of the blast waves by dividing the tunnel into four zones. The paper modifies the decay equation proposed by Smith and applies it to the Micangshan highway tunnel in China. The decay equations are different in different zones. Field tests in this tunnel show that the modified equation is more suitable to describe the attenuation of the blast waves in the tunnel than the original equation.

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Figuli, Lucia, Damjan Cekerevac, Chiara Bedon, and Bohuš Leitner. "Numerical Analysis of the Blast Wave Propagation due to Various Explosive Charges." Advances in Civil Engineering 2020 (October 5, 2020): 1–11. http://dx.doi.org/10.1155/2020/8871412.

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Blast events and scenarios, as known, represent extreme phenomena that may result in catastrophic consequences, both for humans and structures. Accordingly, for engineering applications, the reliable description of expected blast waves is a crucial step of the overall design process. Compared to ideal theoretical formulations, however, real explosive events can be strongly sensitive to a multitude of parameters and first of all to the basic features (size, type, shape, etc.) of the charge. In this regard, several advanced computer codes can be used in support of design and research developments. Besides, the input parameters and solving assumptions of refined numerical methods are often available and calibrated in the literature for specific configurations only. In this paper, with the support of the ANSYS Autodyn program, special care is dedicated to the numerical analysis of the blast wave propagation in the air due to several charges. Five different explosives are taken into account in this study, including RDX, DAP-2, DAP-E, Polonit-V, and homemade ANFO. The effects of different mixtures are thus emphasized in terms of the predicted blast wave, as a function of a given control point, direction, explosive mass, and composition. As shown, relatively scattered peak pressure estimates are collected for a given explosive. Comparative results are hence proposed towards selected experimental data of the literature, as well as based on simple analytical predictions. The collected overpressure peak values are thus discussed for the selected explosive charges.

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Downes, Devon, Amal Bouamoul, Simon Ouellet, and Manouchehr Nejad Ensan. "Development and validation of a biofidelic head form model to assess blast-induced traumatic brain injury." Journal of Defense Modeling and Simulation: Applications, Methodology, Technology 15, no. 3 (2017): 257–67. http://dx.doi.org/10.1177/1548512917737634.

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Traumatic Blast Injury (TBI) associated with the human head is caused by exposure to a blast loading, resulting in decreased level of consciousness, skull fracture, lesions, or death. This paper presents the simulation of blast loading of a human head form from a free-field blast with the end goal of providing insight into how TBI develops in the human head. The developed numerical model contains all the major components of the human head, the skull, and brain, including the tentorium, cerebral falx, and gray and white matter. A nonlinear finite element analysis was employed to perform the simulation using the Arbitrary Lagrangian–Eulerian finite element method. The simulation captures the propagation of the blast wave through the air, its interaction with the skull, and its transition into the brain matter. The model quantifies the pressure histories of the blast wave from the explosive source to the overpressure on the skull and the intracranial pressure. This paper discusses the technical approach used to model the head, the outcome from the analysis, and the implication of the results on brain injury.

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OTSUKA, Teruhito, Hiroyasu SAITOH, and Norihiko YOSHIKAWA. "Scaling Law of Flame Propagation Velocity and Blast Pressure in Hydrogen-Air Deflagration(Thermal Engineering)." Transactions of the Japan Society of Mechanical Engineers Series B 76, no. 772 (2010): 2249–57. http://dx.doi.org/10.1299/kikaib.76.772_2249.

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Li, Runzhi, Zhigang Zhang, Rongjun Si, et al. "Experimental Study on Injuries to Animals Caused by a Gas Explosion in a Large Test Laneway." Shock and Vibration 2021 (April 5, 2021): 1–9. http://dx.doi.org/10.1155/2021/6632654.

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Gas explosion accidents in underground coal mines caused a significant number of casualties. By using a large laneway test system, the damage to Sprague-Dawley (SD) rats at locations at different distances from the source of ignition along the direction of propagation of an explosion was investigated after 100 m3 of the gas-air mixture was ignited and exploded. In this way, the data pertaining to explosion flames and explosion pressures at different propagation distances were obtained to investigate the propagation of explosion flames and explosion pressures along the laneway. Besides, the damage to SD rats at different propagation distances was statistically analyzed. Furthermore, the damage mechanism of explosion flames, explosion pressures, and hazardous gases on humans or animals was discussed. The results indicated that explosive blast injury induced by the gas explosion was the primary reason for the death of animals and SD rats at a distance equal to or greater than 80 m from the point of ignition under the effects of an explosive blast even though SD rats at a distance of 240 m were killed. During the explosion of 100 m3 of mixed gas, the explosion flames propagated 40 m from the point of ignition, and the SD rats in the cage located some 40 m from the point of ignition were subjected to combined damage involving being burned at high temperature and suffering the effects of the explosive blast. These findings provide a theoretical basis for emergency rescue and salvage after gas explosion accidents in underground coal mines.

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Yang, Xin, Xiangguo Zeng, Chuanjin Pu, and Dingjun Xiao. "Effect of the Preexisting Fissure with Different Fillings in PMMA on Blast-Induced Crack Propagation." Advances in Materials Science and Engineering 2018 (July 8, 2018): 1–17. http://dx.doi.org/10.1155/2018/7378282.

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In order to study the dynamic crack propagation law in fissured rock under the different fillings, a borehole with 7 mm diameter was processed in the center of a polymethyl methacrylate (PMMA) specimen. The preexisting fissure with different angles (θ = 0°, 45°, and 90°) and different distances (L = 20, 30, 40, 50, and 60 mm) was prefabricated around the borehole. Air, soil, and water were employed as fillings in the fissure, respectively. The experiment of explosive loading was carried out by a single detonator, and the dynamic crack propagation process of the experimental specimens was simulated by nonlinear dynamics software AUTODYN. The results show that the blast-induced cracks are the most favorable and unfavorable to propagate when θ = 0° and θ = 45°, respectively. The length of the far-end wing crack decreases with the increase of the distance L, and the length of the far-end wing crack in the air-filled specimens is larger than those in soil-filled and water-filled specimens. The damage-pressure curve of the far-end wing crack initiation point shows “S”-type change, and the damage-pressure curve shows two obvious damage evolution processes of initial nonlinear and later linear stages. With the increase of the angle, the distance from the borehole to the crack initiation point decreases and the compressive stress wave peak value should increase, but the tensile force peak value decreases. Meanwhile, the relationships between pressure and average velocity of the initiation point and L, θ, and fillings are established, respectively. The numerical simulation agrees with the experimental results well. It can be seen that the fillings types, angle, and distance have a mutual restraint relationship with the reflected and absorbed stress wave energy. The phenomenon of crack propagation under different fillings can be explained well from the viewpoint of discontinuity degree and stress wave energy, which reveals the general law of blast-induced crack propagation.

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Thakur, Prabhanjan Kumar, Rajesh Mishra, Rajesh Kumar Tanwar, Ghanshyam Kumar Mishra, and Rajiv Narang. "Design and Validation of Blast Non-propagation Wall for Multi-Compartmented Explosive Storage Structure of Capacity 5T NEC per Compartment." Defence Science Journal 68, no. 5 (2018): 432–37. http://dx.doi.org/10.14429/dsj.68.12263.

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Conventional magazines for hazard division 1.1 are constructed using bricks and reinforced cement concrete (RCC) for which storage inside quantity distance (SIQD) is 2.4 W1/3 m, where W is Net Explosive Content in kg. New composite called laced reinforced concrete (LRC) has been developed recently, for which SIQD has been reduced up to 0.5 W1/3 m. Due to substantial reduction in separation distances, the requirement of land area has been reduced significantly. Although SIQD has been reduced drastically due to development of new composite, the other quantity distances like process inside quantity distance (PIQD) and outside quantity distance (OQD) decreased marginally. To reduce these quantity distances, the solution is multi-compartmented structures based on Unit Risk Principle. The application of unit risk principle enables the separation of explosives into compartments in such a manner that initiation of explosives in one compartment does not result in initiation of the explosives in adjacent compartments. This is achieved by special design of explosive storage buildings incorporating blast non-propagation walls between adjacent compartments storing explosives. Quantity distances are reduced for such magazines, as maximum credible limit corresponds to the quantity of explosive in one compartment. Present paper describes design and full scale testing of blast non-propagation wall between two compartments of a multi-compartmented explosive storage structure with storage capacity of 5 T Net Explosive Content (NEC) of HD 1.1 per compartment. The blast non-propagation wall comprising of sand filling and air gap between LRC walls has been designed for desired attenuation of blast parameters as well as for arresting high velocity fragments/debris. The design has been validated by fully instrumented design validation field trial. The conduct of the trial as well as the results are discussed in this paper.

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Jestin, J., Ali Faisal, Ahmad Zaidi Ahmad Mujahid, and Othman Mohd Zaid. "Comparative Study of Small Scale Soil Barrier Subjected to Air Blast Load by Using AUTODYN 2D and AUTODYN 3D." Materials Science Forum 819 (June 2015): 417–22. http://dx.doi.org/10.4028/www.scientific.net/msf.819.417.

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This paper presents the blast loading of small scale soil barrier subjected to surface burst,analysed by using AUTODYN 2D and AUTODYN 3D.Results from the AUTODYN analyses are then compared with published experimental results. Good agreements with published experimental results are obtained for numerical analysis by using AUTODYN 3D for peak pressure at the front part of the barrier. In this case study, AUTODYN 2D numerical analyses provide higher pressure readingsat about 62% and 36% differences as compared with the published experimental results for pressure measurement at the middle front and back of soil barrier surface. The discrepancy of AUTODYN2D results was due to geometric dissimilarity from the actual experimental test. For complex geometries shape of barrier, that involves different shapes and configurations, three dimensional analyses are required to accurately predict the complex reflections and interactions associated with the propagation of the blast wave.

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Lidner, Michał, and Zbigniew Szcześniak. "Numerical Analysis of Blast Load from Explosive Materials Using Finite Volume Method." Key Engineering Materials 723 (December 2016): 789–94. http://dx.doi.org/10.4028/www.scientific.net/kem.723.789.

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A method of numerical analysis of the phenomenon of the air shock wave propagation is presented. The paper describes an explicit own solution. It uses Finite Volume Method (FVM). It also takes into account energy losses due to a heat transfer. For validation, the results of numerical analysis were compared with the literature reports. Both one-dimensional (an explosion in the pipe) and three-dimensional (explosion within the compartment) flow of a shock wave were analysed. Values of impulse, pressure, and its duration were studied. Finally, an overall good convergence of numerical results with experiments was achieved. Also the most important parameters were well reflected.

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Lieberthal, Brandon, D. Scott Stewart, and Alberto Hernández. "Geometrical shock dynamics applied to condensed phase materials." Journal of Fluid Mechanics 828 (August 31, 2017): 104–34. http://dx.doi.org/10.1017/jfm.2017.497.

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Taylor blast wave (TBW) theory and geometrical shock dynamics (GSD) theory describe a radially expanding shock wave front through an inert material, typically an ideal gas, in the strong blast wave limit and weak acoustic limit respectively. We simulate a radially expanding blast shock in air using a hydrodynamic simulation code and numerically describe the intermediate region between these two limits. We test our description of the intermediate shock phase through a two-dimensional simulation of the Bryson and Gross experiment. We then apply the principles of GSD to materials that follow the Mie–Gruneisen equation of state, such as plastics and metals, and derive an equation that accurately relates the acceleration, velocity and curvature of the shock through these materials. Along with detonation shock dynamics (DSD), which describes detonation shock propagation through high explosive fluids, we develop a hybrid DSD/GSD model for the simulation of heterogeneous explosives. This model enables computationally efficient simulation of the shock front in high explosive/inert mixtures consisting of simple or complex geometric configurations. We simulate an infinite two-dimensional slab consisting of one half explosive, PBXN-9, and one half aluminium and model the boundary angle conditions using shock polar analysis. We also simulate a series of high explosive unit cells embedded with aluminium spherical particles, and we compare the propagation of the detonation shock front with a direct numerical simulation performed with the ALE3D code.

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Noorpoor, Zeinab, Saeed Tavangar, Hosein Soury, and Seyed Ghorban Hosseini. "A Computational Fluid Dynamics approach for air blast propagation using OpenFOAM and Becker-Kistiakowsky-Wilson equation of state." Heliyon 6, no. 12 (2020): e05852. http://dx.doi.org/10.1016/j.heliyon.2020.e05852.

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Vivek, Padmanabha, and Thallak G. Sitharam. "Laboratory scale investigation of stress wave propagation and vibrational characteristics in sand when subjected to air-blast loading." International Journal of Impact Engineering 114 (April 2018): 169–81. http://dx.doi.org/10.1016/j.ijimpeng.2018.01.003.

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Tyas, Andrew, Terry Bennett, James A. Warren, Stephen D. Fay, and Sam E. Rigby. "Clearing of Blast Waves on Finite-Sized Targets – an Overlooked Approach." Applied Mechanics and Materials 82 (July 2011): 669–74. http://dx.doi.org/10.4028/www.scientific.net/amm.82.669.

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The total impulse imparted to a target by an impinging blast wave is a key loading parameter for the design of blast-resistant structures and façades. Simple, semi-empirical approaches for the prediction of blast impulse on a structure are well established and are accurate in cases where the lateral dimensions of the structure are sufficiently large. However, if the lateral dimensions of the target are relatively small in comparison to the length of the incoming blast wave, air flow around the edges of the structure will lead to the propagation of rarefaction or clearing waves across the face of the target, resulting in a premature reduction of load and hence, a reduction in the total impulse imparted to the structure. This effect is well-known; semi-empirical models for the prediction of clearing exist, but several recent numerical and experimental studies have cast doubt on their accuracy and physical basis. In fact, this issue was addressed over half a century ago in a little known technical report at the Sandia Laboratory, USA. This paper presents the basis of this overlooked method along with predictions of the clearing effect. These predictions, which are very simple to incorporate in predictions of blast loading, have been carefully validated by the current authors, by experimental testing and numerical modelling. The paper presents a discussion of the limits of the method, concluding that it is accurate for relatively long stand-off blast loading events, and giving some indication of improvements that are necessary if the method is to be applicable to shorter stand-off cases.

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Hashemi, S. K., and Mark A. Bradford. "Numerical Simulation of Free-Air Explosion Using LS-DYNA." Applied Mechanics and Materials 553 (May 2014): 780–85. http://dx.doi.org/10.4028/www.scientific.net/amm.553.780.

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The development of advanced computational technologies in recent years has seen studies of the effects of explosions on large structures becoming feasible and, as a consequence, the number of destructive tests and their high cost can be reduced significantly. This paper presents a study of air-burst explosion wave propagation using computational modelling based on LS-DYNA. Incident and reflected pressure waves are investigated, as well as the mesh sensitivity, different scaled distances and the charge shape. The Multi-Material Arbitrary Lagrangian-Eulerian (MM-ALE) representation is used to model the blast, and the results are validated by empirical methods. The effects of parameter values adopted in these methods are studied. The results show that LS-DYNA can effectively simulate an air-burst explosion. Additionally, the mesh size and explosive weight have a large influence on the peak incident and reflected pressures. It is observed that there is an optimum range of the mesh size in relation to the explosive weight, material properties and the scaled distance which can significantly reduce the CPU usage while having reasonable accuracy. Different charge shapes cause different pressure distributions over the air domain.

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Song, Yanqi, Xiangshang Li, Deyong Guo, and Bokang Shi. "Study on the Decoupled Charge Effect in Deep-Hole Cumulative Blasting of Coal Seam." Advances in Civil Engineering 2019 (April 15, 2019): 1–9. http://dx.doi.org/10.1155/2019/8486198.

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Five models of cumulative blasting are established by using ANSYS/LS-DYNA to study the effect of decoupling coefficient on cumulative blasting to improve coal seam permeability. The formation and migration process of the shaped energy jets with two kinds of decoupling coefficient are compared and analyzed; also, the propagation of explosive stress waves is represented. The result showed that the air in the blast hole is the key to the formation and migration of the condensing jet. The air in the hole also could reduce the attenuation of stress wave in a certain range. However, if the decoupling coefficient is too large, the air in the hole will consume excessive explosive energy, which is also not conducive to energy transfer. Therefore, there is an optimum decoupling coefficient which can minimize the coal crushing area, increase the coal fissure area, and improve the gas extraction rate. Besides, the cumulative blasting tests were carried out in a coal seam. The test results show that decoupling charge could effectively improve coal seam permeability, and the blasting effect was better when the decoupling coefficient is between 1.67 and 2.

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Rosato, Daniel A., Mason Thornton, Jonathan Sosa, Christian Bachman, Gabriel B. Goodwin, and Kareem A. Ahmed. "Stabilized detonation for hypersonic propulsion." Proceedings of the National Academy of Sciences 118, no. 20 (2021): e2102244118. http://dx.doi.org/10.1073/pnas.2102244118.

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Future terrestrial and interplanetary travel will require high-speed flight and reentry in planetary atmospheres by way of robust, controllable means. This, in large part, hinges on having reliable propulsion systems for hypersonic and supersonic flight. Given the availability of fuels as propellants, we likely will rely on some form of chemical or nuclear propulsion, which means using various forms of exothermic reactions and therefore combustion waves. Such waves may be deflagrations, which are subsonic reaction waves, or detonations, which are ultrahigh-speed supersonic reaction waves. Detonations are an extremely efficient, highly energetic mode of reaction generally associated with intense blast explosions and supernovas. Detonation-based propulsion systems are now of considerable interest because of their potential use for greater propulsion power compared to deflagration-based systems. An understanding of the ignition, propagation, and stability of detonation waves is critical to harnessing their propulsive potential and depends on our ability to study them in a laboratory setting. Here we present a unique experimental configuration, a hypersonic high-enthalpy reaction facility that produces a detonation that is fixed in space, which is crucial for controlling and harnessing the reaction power. A standing oblique detonation wave, stabilized on a ramp, is created in a hypersonic flow of hydrogen and air. Flow diagnostics, such as high-speed shadowgraph and chemiluminescence imaging, show detonation initiation and stabilization and are corroborated through comparison to simulations. This breakthrough in experimental analysis allows for a possible pathway to develop and integrate ultra-high-speed detonation technology enabling hypersonic propulsion and advanced power systems.

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Koznacheev, I. A., and K. V. Dobrego. "Mutual Dynamics of Heat Dissipation and Oil Displacement Fronts during In-Situ Oil Combustion. One-Dimensional Simulation." ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 62, no. 5 (2019): 445–58. http://dx.doi.org/10.21122/1029-7448-2019-62-5-445-458.

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One-dimensional axis-symmetrical and plane-symmetrical problem of propagation of the combustion and displacement fronts in oil-containing layer in situ has been considered numerically. Two combustible components, viz. liquid (oil) and solid (kerogen, oil sorbate), were considered. The influence of the blast rate, liquid component viscosity, oxygen concentration in blasted air and heat losses (the width of the oil-containing layer) on the dynamics of the heat dissipation and displacement fronts is investigated. In the cylindrical system the oxidizer flow to the combustion front is reducing over time; and the shift-down of the maximum temperature from the solid combustion front to the oil displacement front takes place (the combustion front “jump”). The time of the “jump” may vary from tenths to hundreds of days and the distance of the shift, – up to 10 or more meters, depending on the parameters of the system. After the “jump”, the combustion rate and maximum temperature continue to deteriorate and after the period of time close to the time lapse before the “jump” the chemical reaction ceases. Herewith the transition of combustion to the liquid phase after the “jump” doesn’t influence notably on oils displacement front speed. The time of the “jump”, as well as the velocity of the mutual combustion (maximum temperature) front and displacement front removal nearly linearly depends on incoming gas blast rate and non-linearly – on oil viscosity. When viscosity is low, the displacement front rapidly runs away from the combustion front, time of the “jump” retards and the distance between the fronts at the instance of the “jump” may reach 10 m or more. The oxygen concentration in the gas being blasted influences significantly on the mutual dynamics of the combustion and displacement fronts since combustion front velocity is proportional to oxygen concentration and displacement front velocity is independent on it. Oxygen enrichment of the gas being blasted just after the “jump” may help localize the area of heat release (combustion) near the oil displacement front. The mentioned manipulation may be utilized for sustainability control of the displacement front. However for its practical implementation it is necessary to have information on concentration and temperature fields inside the layer, which may be obtained from indirect data and via modeling. The results of investigation may be utilized for development of technical projects of oil recovery via in-situ combustion.

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Qiu, Xiao, Jue Ding, Zhong Jie Wang, and Pei Feng Weng. "The Similarity Law of Internal-Blast Wave Propagation in the Concrete." Advanced Materials Research 1065-1069 (December 2014): 1143–46. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.1143.

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Concrete mechanical properties under dynamic load such as blast and impact are very complex. Shock wave propagation law and damage effect in the concrete were studied numerically in the paper by using TNT explosive ignition and growth model, concrete dynamic damage model, and SPH method. And shock wave properties of different mass explosives in the concrete were analyzed with the similarity theory. The result shows that TNT shock wave propagation law meets the internal-blast similarity law. Peak pressure, positive pressure impulse, maximum velocity and maximum acceleration in the concrete decrease with the increase of scaled distance. And time needed for reaching peak pressure increases linearly with the increase of scaled distance. A theoretical basis of structure and protection design for constructions is achieved in the paper.

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Wu, Sai, Jun Hai Zhao, and Er Gang Xiong. "Finite Element Analysis on the Blast Resistant Performance of Multibarrel Tube-Confined Concrete Column in Different Cross-Sections." Advanced Materials Research 721 (July 2013): 545–50. http://dx.doi.org/10.4028/www.scientific.net/amr.721.545.

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Based on the finite element analysis software ANSYS/LS-DYNA, this paper numerically analyzed the dynamic performance of MTCCCs with different cross sections under blast load, followed by the study and comparison on the differences of the detonation wave propagation and failure modes between the columns in circular cross section and square cross section. The results show: The blast resistant performance of the circular component is more superior than the square component for its better aerodynamic shape that can greatly reduce the impact of the detonation wave on the column; The main difference of the failure modes between the circular and square cross-sectional components under blast load lies in the different failure mode of the outer steel tube. The simulation results in this paper can provide some references for the blast resisting design of MTCCCs.

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Li, Xiao Yong, Cun Yan Cui, Jing Peng Chen, Yun Chun Jiang, Bei Lei Zhao, and Xing Li. "Numerical Simulation of Blast Wave Propagating on the Soil Surface." Applied Mechanics and Materials 602-605 (August 2014): 3256–60. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.3256.

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A numerical simulation of TNT explosion on the soil surface is presented in this paper. It demonstrates how the blast wave propagates on the soil surface and interacts with the soil surface. Compared with the explosion in air, a comparative analysis on the distribution of the shock wave overpressure is implemented. The results show that the space on the soil surface close to the explosion source can be divided into a relatively high pressure region and a relatively low pressure region. Moreover, by defining the scaled height H, the interface of two regions comes about H = 0.35.

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Yang, Fan, Li He, Xiao Liu, and Bin Jia. "Numerical Simulation of Explosion in a Confined Box-Shaped Structure." Advanced Materials Research 671-674 (March 2013): 3204–7. http://dx.doi.org/10.4028/www.scientific.net/amr.671-674.3204.

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In order to study the propagation law of shock wave and blast load distribution when an interior explosion occur in a box structure, a numerical simulation of an interior explosion within a box-shaped structure is presented in this paper using LS-DYNA. Overpressure-time history curve of the blast load at the measured points is obtained by numerical simulation, and compared with the experimental results. Numerical simulation results and experimental results are in good agreement. The results show that the blast wave reflected and superimposed many times in the box-shaped structure. When TNT is located in the center of the box-shaped structure, the center and the corner of the wall suffered the maximum overpressure.

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Chen, Baobao, Changyou Liu, and Jingxuan Yang. "Design and Application of Blasting Parameters for Presplitting Hard Roof with the Aid of Empty-Hole Effect." Shock and Vibration 2018 (September 2, 2018): 1–16. http://dx.doi.org/10.1155/2018/8749415.

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Theoretical calculation and numerical simulation were performed to analyze the mechanism of rock fracturing between holes in deep-hole presplit blasting, crack evolution under the synergistic action of dynamic and static loads, and the mechanism of fracture movement guided by tangential stress concentration of empty holes. The pattern and characteristic zones of main and wing cracks across a cross section were identified. Combined with blast dynamics, the scope of stress-induced cracks around blast holes and the maximum length of secondary cracks induced by detonation gas was calculated. It was found that the initiation and extension of cracks were oriented predominantly along the line passing through the hole centers (LPTHC). Moreover, the maximum length of the tensile crack zone induced by reflected stress waves was obtained. The effects of empty-hole diameter and charge coefficient on crack propagation were analyzed, and the proper blast-hole spacing was determined. Later, a LS-DYNA3D blast model was used to illustrate von Mises stress propagation, strain variation, and evolution of main and wing cracks between holes. The scope of strain failure, fracture pattern, and crack characteristic zones in the rock mass was determined. The results demonstrate that the hole spacing, at 3.2 m, is reasonable. Furthermore, blasting parameters were determined for 8939 working face at Xinzhouyao Mine and then deep-hole blasting was implemented to presplit the hard roof. After presplitting, the working resistance of supports was significantly reduced, thereby achieving effective control on the hard roof.

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Fan, Jun Qi, Jun Xia Yang, Fu Li Kong, and Kui Huang. "A Theoretical Model on Blast Lung Injury from an Explosion." Advanced Materials Research 850-851 (December 2013): 1220–24. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.1220.

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About the prediction of the biological damage effects on the lung of human under explosion wave, there are three different criterions, including excessive pressure-impulse criterion, kinematic velocity criterion and specific energy criterion. In the paper, based on the established three criterions and the practical anatomical structure of lung , a new theoretical model on blast lung injury from an explosion is developed. In the present model, the problem of blast lung injury is simplified as the one-dimensional propagation of stress wave in metal foam. Results show that the failure stress of the lung is 0.036~0.072 MPa, and the three criterions can convert to each other.

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Li, Shu Fang, and Shi Liang Chu. "Prediction Model of Silicon Content in Hot Metal Using Optimized BP Network." Advanced Materials Research 933 (May 2014): 206–11. http://dx.doi.org/10.4028/www.scientific.net/amr.933.206.

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In the course of systematic modeling, the artificial neural networks method is studied. In allusion to the defect of grads descension of traditional back propagation network algorithms, some improving measures have been taken to determine the optimal prediction and analysis model. These measures include adaptive learning, additive momentum, reasonable selection of drive function, and using genetic algorithm to optimize the input parameters. And to learn and predict the utilization of blast furnace production data, better application result is acquired.

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Kao, Chin Ming, Li Chen, Chang Huan Kou, and Shih Wei Ma. "Applying Back-Propagation Neural Network for Estimating the Slump of Concrete." Advanced Materials Research 651 (January 2013): 986–89. http://dx.doi.org/10.4028/www.scientific.net/amr.651.986.

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This paper proposes the back-propagation neural network (BPN) and applies it to estimate the slump of high-performance concrete (HPC). It is known that HPC is a highly complex material whose behaviour is difficult to model, especially for slump. To estimate the slump, it is a nonlinear function of the content of all concrete ingredients, including cement, fly ash, blast furnace slag, water, superplasticizer, and coarse and fine aggregate. Therefore, slump estimation is set as a function of the content of these seven concrete ingredients and additional four important ratios. The results show that BPN obtains a more accurate mathematical equation through learning procedures which outperforms the traditional multiple linear regression analysis (RA), with lower estimating errors for predicting the HPC slump.

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Dong, Yong Xiang, Shun Shan Feng, Xiang Jie Duan, and Li Xing Xiao. "Influence of Soft Interlayer in Concrete Sandwich Panel on Propagation Characteristics of Plane Explosive Wave." Advanced Materials Research 255-260 (May 2011): 2370–74. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.2370.

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The propagation characteristics and laws of concrete sandwich with foam soft interlayer under contact explosion were studied by numerical simulation. Based on a reasonable choice of the constitutive model and physical parameters by numerical methods, the plane blast wave propagation features of the concrete structure are illustrated, including the stress wave propagation and attenuation, space-time evolution of damage and wave reflection and transmission at layered interfaces, and the total energy distribution in various medium layers. The structural failure and destruction of two-dimensional dynamic process was reproduced by numerical computation. Meanwhile, it is pointed out that the role of soft interlayer in concrete sandwich structure is mainly by its low wave impedance, the waveform of incident wave is changed and stress wavelength is pull wide, the radial diffusion of energy is enhanced and the amplitude of impulse and energy inputting the third layer is reduced, thus as a result the protective performance of overall concrete sandwich structure is improved.

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Bílek Jr., Vlastimil, Libor Topolář, Hana Šimonová, et al. "Pilot Study of the Effect of Admixtures in Fine-Grained Cement-Based Composites on Volume Changes and Fracture Parameters." Advanced Materials Research 969 (June 2014): 294–97. http://dx.doi.org/10.4028/www.scientific.net/amr.969.294.

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The partial replacement of cement in concrete by an alternative admixture is a current topic in materials engineering. In order to examine the effect of replacing 20 % of the weight of Portland cement in fine-grained concrete using selected admixtures on volume changes and mechanical fracture parameter values, a set of specimens was fabricated from these quasi-brittle materials. Granulated blast-furnace slag, high-temperature fly ash, metakaolin and specially selected combinations of them were used as admixtures. Three-point bending fracture tests were conducted on these specimens and load versus crack mouth opening displacement (PCMOD) diagrams were recorded during the testing. In this paper, the outputs of the double-K fracture model were used for the prediction of beginning of stable crack propagation in fine-grained cement-based composites with admixtures.

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Xu, Peng Cheng, Qian Dong, Xin Ping Li, and Yi Luo. "Influence Research of Underground Caverns Blasting Excavation on Excavation Damage Zone of Adjacent Cavern." Advanced Materials Research 838-841 (November 2013): 901–6. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.901.

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The influence of the single cavern blasting excavation in underground caverns on the stability of surrounding rock of adjacent caverns can not be ignored.In–situ blasting vibration test and dynamic finite element analysis were used to study the laws of blasting seismic wave propagation, two different material constitutive models were adopted, compared with measured data,to select material constitutive model which was more in line with the dynamic characteristics of rock mass in underground caverns.On this basis, the influence mechanism for blast–induced EDZ(Excavation Damage Zone) of the adjacent cavern is studied through the method of numerical simulation. The results show that the numerical simulation resulted by adopting kinematic hardening model were more close to measured data than adopting ideal elastic–plastic model; the middle part of adjacent tunnel side wall facing blasting had the largest damaged rock mass range; both sides of the arch and the foundation rock of the adjacent cavern emerged damaged rock mass area, and the area of adjacent tunnel side wall facing blasting was larger than side wall not facing blasting.

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Kitov, I. O., J. R. Murphy, O. P. Kusnetsov, B. W. Barker, and N. I. Nedoshivin. "An analysis of seismic and acoustic signals measured from a series of atmospheric and near-surface explosions." Bulletin of the Seismological Society of America 87, no. 6 (1997): 1553–62. http://dx.doi.org/10.1785/bssa0870061553.

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Abstract During December 1985, Soviet scientists monitored a series of high-explosive tests at a bombing range near Kustanai, Kazakhstan, in which both seismic and acoustic data were recorded at distances of 6, 9.5, and 21 km from bomb blasts at different altitudes. These data show a remarkable variety of seismo/acoustic phenomena associated with energy conversion processes at the Earth's surface, including air-coupled Rayleigh waves and acoustic signals produced by propagating seismic disturbances having phase velocities near the speed of sound in air. These data provide valuable new insights into the mechanisms responsible for the generation of seismic and acoustic signals by atmospheric and near-surface explosions. In particular, theoretical simulation results are presented that are shown to account for most of the features of the observed data, and, therefore, it is concluded that the simplified theoretical models employed in these simulations can provide a quantitative basis for assessing the effects of source and site conditions on the characteristics of the signals produced by such explosions.

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Chitombo, Gideon. "Importance of Geology in Cave Mining." SEG Discovery, no. 119 (October 1, 2019): 1–21. http://dx.doi.org/10.5382/geo-and-mining-05.

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Editor’s note: The Geology and Mining series, edited by Dan Wood and Jeffrey Hedenquist, is designed to introduce early-career professionals and students to a variety of topics in mineral exploration, development, and mining, in order to provide insight into the many ways in which geoscientists contribute to the mineral industry. Abstract Cave mining methods (generically referred to as block caving) are becoming the preferred mass underground mining options for large, regularly shaped mineral deposits that are too deep to mine by open pit. The depth at which caving is initiated has increased over the past few decades, and operational difficulties experienced in these new mines have indicated the need for a much improved geologic and geotechnical understanding of the rock mass, if the low-cost and high-productivity objectives of the method are to be maintained and the mines operated safely. Undercuts (the caving initiation level immediately above the ore extraction level) are now being developed at depths of &gt;1,000 m below surface, with the objective of progressively deepening to 2,000 and, eventually, 3,000 m. Many of the deeper deposits now being mined by caving have lower average metal grades than previously caved at shallower depths and comprise harder and more heterogeneous rock masses, and some are located in higher-stress and higher-temperature environments. As a result, larger caving block heights are required for engineering reasons; mining costs (capital and operating) are also escalating. In these deeper cave mining environments, numerous hazards must be mitigated if safety, productivity, and profitability are not to be adversely affected. Fortunately, potential hazards can be indicated and evaluated during exploration, discovery, and deposit assessment, prior to mine design and planning. Major hazards include rock bursts, air blasts, discontinuous surface subsidence, and inrushes of fines. These hazards are present during all stages of the caving process, from cave establishment (tunnel and underground infrastructure development, drawbell opening, and undercutting) through cave propagation and cave breakthrough to surface, up to and including steady-state production. Improved geologic input into mine design and planning will facilitate recognition and management of these risks, mitigating their consequences.

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Sil, Arjun, and Diptimoyee Phukan. "Quantification and analysis of air blast load propagation characteristics on structures." Journal of Building Pathology and Rehabilitation 4, no. 1 (2019). http://dx.doi.org/10.1007/s41024-019-0063-7.

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Suresh, C., and K. Ramajeyathilagam. "Numerical Investigation of Thin Plate Subjected to Blast Wave Propagation in Air and Water." International Journal of Vehicle Structures and Systems 11, no. 5 (2019). http://dx.doi.org/10.4273/ijvss.11.5.06.

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Numerical investigations on a thin rectangular plate subjected to air blast and underwater using LS DYNA is presented in this paper. For the analysis, the box model setup, air/water medium and target plate are modelled and the explosive is assumed at a distance of 150 mm from the target plate at the normal line passing through the centre of the plate. The target plate is modelled using piece-wise linear plasticity material model, the fluid using Gruinesian equation of state, air using linear polynomial equation of state and explosive using JWL equation of state. Parametric study in terms of charge weight is carried and the results are presented for various shock factors. The free field pressure time history and the permanent deformation are compared with experimental results available in literature. The study indicates that the permanent deformation is about 5.5 times that of air blast in underwater explosion.

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Bayarsaikhan, Ch, M. Ulziibat, L. Tungalag, Ch Lkhagvajav, and Alexis Le Pichon. "Analysis of Infrasound Propagation at Regional Distance by Mining Explosion." Proceedings of the Mongolian Academy of Sciences, March 18, 2011, 42–52. http://dx.doi.org/10.5564/pmas.v0i4.45.

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Seismic and acoustic recordings are particularly important to help identifying and locating industrial blasting sources. We have analyzed seismo-acoustic signals from mine blast for 2000 and 2005 in order to determine detection seismo-acoustic signals of explosion by seismic and infrasound stations. Several large mines in the region routinely generate explosions that are detected seismically and with infrasound. The mine range in distance from 40-500 km from the seismic, infrasound array. In last few years mining activity in Mongolia significantly increased. All events identified as quarry blasts have occurred during daytimes between 03:00 p.m. and 08:00 a.m. GMT and on weekdays from Monday to Friday. The corresponding number of infrasound detection is found to be dependent upon the regional weather condition, which is included air temperature, epicentral distance, wind force and velocity. We present the seismic and infrasound IMS stations and some results of analysis.DOI: http://dx.doi.org/10.5564/pmas.v0i4.45 Proceedings of the Mongolian Academy of Sciences 2009 No 4 pp.42-52

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Costa, Emiliano. "Assessment of a coupled approach to determine the stress caused by gun blast loads." Journal of Defense Modeling and Simulation: Applications, Methodology, Technology, December 17, 2019, 154851291989233. http://dx.doi.org/10.1177/1548512919892337.

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This paper aims at assessing a custom numerical procedure built to predict the level of stress in the structural components and equipment in proximity of a cannon-like weapon system when firing. In such a blast scenario, the structures adjacent to a gun may undergo sudden and unwanted damages, since they are commonly subjected to the blast load due to the impingement and propagation of the shock waves expanding from the weapon muzzle. The proposed procedure pertains the coupled use of an in-house developed tool (GUNWave3D) based on the power-law scaling technique and a general-purpose commercial fast dynamic solver to compute the structural response of the loaded components. The in-house tool, in particular, allows one to rapidly calculate the blast parameters over the surfaces of the items of interest in the function of the weapon characteristics and launch conditions, also accounting for the asymmetric shape characterizing the gun blast wave. Taking as reference the numerical free field peak overpressure profiles of a 30 mm gun, whose blast quantities were already validated in a previously published work, the final stage of the assessment was accomplished. Such an estimation consists of the comparison between the structural stresses calculated using the blast loads predicted through the in-house tool and those computed adopting the free spherical air blast of the tri-nitro-toluene model. This operation has the objective to quantify the discrepancy between the computational results of two Lagrangian techniques that can be alternatively adopted in industrial gun blast design procedures and methodologies.

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Hutchinson, John W. "Energy and Momentum Transfer in Air Shocks." Journal of Applied Mechanics 76, no. 5 (2009). http://dx.doi.org/10.1115/1.3129773.

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A series of one-dimensional studies is presented to reveal basic aspects of momentum and energy transfer to plates in air blasts. Intense air waves are initiated as either an isolated propagating wave or by the sudden release of a highly compressed air layer. Wave momentum is determined in terms of the energy characterizing the compressed layer. The interaction of intense waves with freestanding plates is computed with emphasis on the momentum and/or energy transferred to the plate. A simple conjecture, backed by numerical simulations, is put forward related to the momentum transmitted to massive plates. The role of the standoff distance between the compressed air layer and the plate is elucidated. Throughout, dimensionless parameters are selected to highlight the most important groups of parameters and to reduce parametric dependencies to the extent possible.

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Journal articles on the topic 'Air blast propagation'

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