Artykuły w czasopismach: „AUTODYN Model”

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Grunwald, Christoph, Benjamin Schaufelberger, Alexander Stolz, Werner Riedel i Thomas Borrvall. "A general concrete model in hydrocodes: Verification and validation of the Riedel–Hiermaier–Thoma model in LS-DYNA". International Journal of Protective Structures 8, nr 1 (marzec 2017): 58–85. http://dx.doi.org/10.1177/2041419617695977.

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The Riedel–Hiermaier–Thoma model, which is available in ANSYS Autodyn since 2000 as a description of concrete and similar geological materials in highly dynamic loading situations, has recently been implemented in the multi-purpose Finite Element code LS-DYNA. This article gives a brief overview of the physical details and verifies the new implementation by comparing single element test results with the established Autodyn code. Four real cases, ranging from low to very high pressure loading by impact, penetration and blast, are used to demonstrate thereafter the validity of the model in a wide range of applications. Simulation results from both codes are compared to experimental data at several occasions. Although slight differences between the implementations are observed, the overall agreement, both between the codes and with experiments, is very good. The systematic work in this publication demonstrates that the Riedel–Hiermaier–Thoma model is a useful addition to the LS-DYNA material library and shall motivate research to apply the model over a wide range of applications. A comprehensive, physically derived dataset is provided for a C70/85 high-strength concrete used in one validation case.

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Hu, Guo, Jun Wu i Liang Li. "Advanced Concrete Model in Hydrocode to Simulate Concrete Structures under Blast Loading". Advances in Civil Engineering 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/7540151.

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The formulations of the advanced concrete RHT model adopted in AUTODYN are investigated and numerical studies are conducted to study the RHT model’s actual performances under various loading conditions. It is found that using of default values in the RHT model is not able to simulate the realistic behavior of concrete under various loading conditions. Thus modified parameters in the RHT model are proposed to better capture the realistic behavior of concrete under such loading conditions. Furthermore, numerical simulation of normal concrete slabs and multilayer concrete slabs subjected to blast loading is conducted using AUTODYN with both the default and modified RHT parameters. Experimental readings from field blast tests are used to validate the numerical model developed. It is shown that the results from numerical simulations using the modified RHT parameters and the measurements from the field blast test agree well in terms of damage pattern, crater diameter, and acceleration. Hence, it can be concluded that the RHT model with modified parameters can capture the mechanical behavior of concrete structures well. The validated model can be further used to conduct a parametric study on the influence of key parameters (i.e., compressive strength, fracture energy, and thickness) on blast resistance of concrete structure.

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Ahmad Mujahid, Ahmad Zaidi, Shah Koslan Md Fuad i Othman Mohd Zaid. "Response of Armour Plate Subjected to Blast Loading Based on Analytical Model of Second Order Single Degree of Freedom". Materials Science Forum 819 (czerwiec 2015): 387–92. http://dx.doi.org/10.4028/www.scientific.net/msf.819.387.

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The rolled homogeneous armour (RHA) plate is commonly used for armoured vehicle skin. Preliminary predictions of the deflections from RHA plate subjected to blast loading is important for establishing guidelines before it is used in vehicle skin. The goal of this work is a reliable technique for predicting the RHA plate response subjected to blast loading, and the empirical result performed by other researchers will be taken as a reference. Based on selected references, a small number of assumptions lead to the developed Single Degree of Freedom (SDOF) idealised models. This paper provides an analytical prediction for the RHA plate response using SDOF in one dimension (1D) approach. The analytical capability was subsequently verified using the non-linear fluid structure interaction (FSI) numerical simulation and the AUTODYN computer code. The midpoint deflections of the RHA plate were taken as the figure of merit. Based on the small error percentage and the support of strong analytical arguments, the second order SDOF analytical approach and numerical simulation using the AUTODYN computer code can be employed as a method of analysis.

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Yarar, Eser, i Alpay Tamer Erturk. "Multiple-Shot Impact Model for Vibration-Assisted SMAT Process". Key Engineering Materials 905 (4.01.2022): 3–8. http://dx.doi.org/10.4028/www.scientific.net/kem.905.3.

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Surface mechanical attrition treatment enhances the mechanical properties of metallic materials by inducing high strength layer on the top surface. In this study, multiple-shot impact behavior was modeled for the 7075-T6 aluminum alloy to achieve maximum magnitudes of equivalent stress, plastic strain, residual stress depth, and residual stress. Finite element simulations have been carried out to investigate the effect of selected framework on stress and strains in constituent. The plastic deformation process during SMAT was analyzed using ANSYS/AUTODYN explicit dynamic solver according to shot velocity and diameter with a dynamic explicit finite element method (FEM). Deformation behavior was evaluated after multiple-shot impact.

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Kamarudin, Khairul H., Ahmad Mujahid Ahmad Zaidi, Ahmad Humaizi Hilmi, Mohamad Faizal Abdullah, Norazman M. Nor, Ariffin Ismail, Mohammed Alias Yusof i S. Rasool Mohideen. "Simulation Study on Hypervelocity Penetration of Lab Scaled Shape Charge Mechanism". Journal of Engineering and Technological Sciences 54, nr 6 (31.12.2022): 220613. http://dx.doi.org/10.5614/j.eng.technol.sci.2022.54.6.13.

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Shaped charge (SC) is a mechanism used by defence industries as anti-armored weapon to penetrate armored plates. Numerous studies have been conducted on the shaped charged effects. However, experimental studies are limited due to great safety requirement and limited access to high grade explosive. Due to these limitations, an experimental study on a small-scale shaped charge mechanism (SCM) penetration blast test was conducted against five (5) types of target materials. The experimental data is then verified by simulation to proof that it can be used to predict the SC penetration data. This paper intent to present a comparative study on the effect of shaped charge blast conducted by simulation with the actual experimental results. In order to conduct this study, a 2D AUTODYN software were used to develop the SC blast model against five (5) types of target materials. This study concludes that the 2D AUTODYN simulations results can predict the hypervelocity penetration for all target materials compared to the experimental test with an average difference of 9.1 %.

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Chen, Qing-hua, Yue-qiu Jiang, Yu-xin Gao, Yu-hang Liu i Jia-qi Yang. "Simplified Algorithm Model for Explosion Shockwave Load in the Cabin". Shock and Vibration 2021 (31.12.2021): 1–12. http://dx.doi.org/10.1155/2021/7726779.

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In order to obtain the shockwave load simplified algorithm model for the semiarmored projectile internal explosion in the cabin, this research made use of AUTODYN to provide a numerical modeling method for explosion in the cabin and verified the accuracy of the method via the experiment. Internal explosion simulation calculation was conducted on the operating condition numerical model with different cabin structural dimensions and different explosive loads. The cabin internal explosion space was divided into the noncorner central area, near-wall area, two-sided corner area, and three-sided corner area. Through regression of the abovementioned calculation results, an engineering model to calculate the shockwave load was obtained. It is hoped that the model can offer some references to the antiexplosion design for the ship cabin and for damage assessment of the internal explosion.

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Mohottige, Nimasha Weerasingha, Chengqing Wu i Hong Hao. "Characteristics of Free Air Blast Loading Due to Simultaneously Detonated Multiple Charges". International Journal of Structural Stability and Dynamics 14, nr 04 (2.04.2014): 1450002. http://dx.doi.org/10.1142/s0219455414500023.

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Extensive research has been conducted to investigate the characteristics of blast load due to single charge explosion, including numerical simulations and experimental blast tests in both unconfined and confined environments. Further, available guidelines for blast resistant design such as UFC-3-340-02 (2008) and ASCE 59-11 (2011) provide details to predict blast loads on a structure subjected to single charge explosion. However, blast load characteristics due to multiple charge explosions are poorly discussed in available literature. In this paper, commercially available Hydrocode, AUTODYN is calibrated for single charge explosions. Based on a comparison between numerical simulation and UFC prediction, correction factors for peak reflected pressure and positive reflected impulse as a function of charge weight, scaled distance and mesh size of the numerical model are proposed to minimize the errors in simulations. The calibrated AUTODYN model is then used to conduct parametric studies to investigate the effects of charge weight, scaled distance, number of charges and distance between the charges on the characteristics of free air blast load due to simultaneous detonated multiple charges. Numerical simulation results are used to derive analytical formulas for predictions of peak reflected pressure ratio and positive reflected impulse ratio between single and multiple explosions. The discussion is made on characteristics of free air blast load due to simultaneous detonated multiple charges.

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Choi, Mijin, Jung-Ryul Lee i Cheol-Won Kong. "Development of a Numerical Model for an Expanding Tube with Linear Explosive Using AUTODYN". Shock and Vibration 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/436156.

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Pyrotechnic devices have been employed in satellite launch vehicle missions, generally for the separation of structural subsystems such as stage and satellite separation. Expanding tubes are linear explosives enclosed by an oval steel tube and have been widely used for pyrotechnic joint separation systems. A numerical model is proposed for the prediction of the proper load of an expanding tube using a nonlinear dynamic analysis code, AUTODYN 2D and 3D. To compute a proper core load, numerical models of the open-ended steel tube and mild detonating tube encasing a high explosive were developed and compared with experimental results. 2D and 3D computational results showed good correlation with ballistic test results. The model will provide more flexibility in expanding tube design, leading to economic benefits in the overall expanding tube development procedure.

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Ding, Yu Qing, Wen Hui Tang, Xian Wen Ran i Xin Xu. "Computational Simulations of Dynamic Compaction of Dry Sand". Advanced Materials Research 598 (listopad 2012): 516–19. http://dx.doi.org/10.4028/www.scientific.net/amr.598.516.

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The computational analysis of plate impact experiments on dry sand utilizing the Mie- Grüneisen (MG) equation of state and the P-α compaction model were investigated in this study. A number of two dimensional axial symmetric computations were performed by using the hydrocode AUTODYN. The computational results were compared with the particle velocity on the back surface of the rear plate measured by the VISAR system and the first shock-wave arrival times detected by piezoelectric pins in the samples respectively. It was found that the P-α compaction model was more accurately reproduce the experimental data than the MG EOS.

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Saravanan, S. "Thermo-Structure Approach to Dissimilar Explosive Cladding with Interlayer". Journal of Physics: Conference Series 2478, nr 4 (1.06.2023): 042014. http://dx.doi.org/10.1088/1742-6596/2478/4/042014.

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Abstract A thermodynamic model capable of predicting the change in internal energy, work done, and thermal energy required during aluminum-stainless steel explosive cladding is presented. The mathematical model is instrumental in determining the temperature and pressure developed at the interface, which characterizes the interface microstructure, compared with the numerical simulation. Numerical simulation is implemented by the Smoothed Particle Hydrodynamics method available in ANSYS Autodyn. Furthermore, the effect of different interlayers, such as Al 1100, copper, and SS 304, on kinetic energy utilization and deformation work is discussed. The increase in ram tensile and shear strengths is also reported.

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Zhou, Zhangtao, Zheming Zhu, XinXing Jin i Hao Tang. "Numerical Prediction of Rock Fracturing During the Process of Excavation". International Journal of Geotechnical Earthquake Engineering 1, nr 2 (lipiec 2010): 12–23. http://dx.doi.org/10.4018/jgee.2010070102.

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During the process of excavation, blasting can induce cracking inside the surrounding rock. Considering the effects of material properties and loading conditions, a rock blasting excavation model with two successive excavation steps was developed through the use of AUTODYN code. Four kinds of equation of state (EOS), linear, shock, JWL, and compaction were applied to the materials employed in this numerical model. A modified principal stress failure criterion was applied to determining material statuses, and TNT explosive and a relatively homogeneous igneous rock, diorite, were used in this numerical model. By using this numerical model, rock fracturing process during blasting excavation was simulated, and rock fracturing process during two successive excavations is presented.

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Xu, Xing Chun, Xin Bao Gao i Bo Bo Zhao. "Dynamics Simulation of Particles of a Smoke Generator Based on SPH Method". Applied Mechanics and Materials 723 (styczeń 2015): 176–80. http://dx.doi.org/10.4028/www.scientific.net/amm.723.176.

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With the increasingly wider use of smoke in informationized warfare, the evaluation of combat effectiveness has become a new research focus in the realm. Hence, there is a need to investigate the dynamics regulation of smoke particles. In this paper, the authors construct a simulation model by analyzing the expanding process of initial smoke cloud. Further, the SPH method was employed in the dynamics simulation. The curves of velocity, displacement and pressure with time were presented after calculation in AUTODYN. The curves from the dynamics simulation show a good consistent when compared to the theoretical model. It proves that the dynamics simulation of smoke particles based on SPH method is feasible.

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Soydan, Ali Murat, Bahadır Tunaboylu, Ahmed Galal Elsabagh, Abdul Kadir Sarı i Recep Akdeniz. "Simulation and Experimental Tests of Ballistic Impact on Composite Laminate Armor". Advances in Materials Science and Engineering 2018 (23.08.2018): 1–12. http://dx.doi.org/10.1155/2018/4696143.

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This paper presents the experimental testing and simulation results of ballistic impact tests on laminated armor samples that consist of three layers of different materials: fiber-cement, Kevlar fabric, and steel. In experimental tests, a 9 mm FMJ bullet was launched towards a 100 cm2 sample of the armor from the fiber-cement side. Ansys Workbench Explicit Dynamics and Ansys AUTODYN 3D were used to model and simulate the ballistic impact. Experimental testing and simulation results were compared to analyze the behavior of composite armor designs, and a good agreement was observed.

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Román, Zsolt. "Convergence Study of 1–D CFD Cell Size for Shockwave Parameters Using Autodyn Hydrocode". Academic and Applied Research in Military and Public Management Science 12, nr 2 (31.12.2013): 213–20. http://dx.doi.org/10.32565/aarms.2013.2.4.

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The use of CFD codes has become widespread to solve the shockwave propagation problem, as they are able to successfully model explosions. Using the structured grid spherically and cylindrical charges cannot be modelled in 3D, thus remapping techniques have been developed to map spherical shockwaves from 1D to 2D and then to 3D. This method highlights the importance of the accuracy of the 1D model, which is mainly dependent on the mesh size. This study aims at finding the required division ratio for the calculation domain.

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Lin, Li, Feng Fan i Xu Dong Zhi. "Numerical Investigation on the Reticulated Domes Subjected to the Multi-Point Impact". Applied Mechanics and Materials 274 (styczeń 2013): 523–26. http://dx.doi.org/10.4028/www.scientific.net/amm.274.523.

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In the present paper, FE model of the single-layer Kiewitt-8 reticulated domes with a span of 60m was built with using of ANSYS/AUTODYN. The dynamic response of the reticulated domes against the multi-point impact was investigated, where a special impactor was involved. Based on the simulation results, four damage modes were concluded，which are local damage, global collapse, local damage with punching plug, punching plug respectively. It was indicated that the initial kinetic energy of the impactor have a close correlation with the damage mode. Furthermore, the characteristics of dynamic response for each damage mode were shown.

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Abdel-Kader, Mohamed. "Numerical predictions of the behaviour of plain concrete targets subjected to impact". International Journal of Protective Structures 9, nr 3 (14.03.2018): 313–46. http://dx.doi.org/10.1177/2041419618759109.

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One widely used model implemented in the hydrocode ANSYS Autodyn is the Riedel–Hiermaier–Thoma material model, which is used for the prediction of concrete behaviour under severe loading, such as blast and impact. In the Riedel–Hiermaier–Thoma model, parameters are adjusted to be a function of the compressive strength of specific concrete. This advantage enables occasional users (and those who cannot conduct experiments to determine all the required concrete parameters) to input only this parameter, while the rest is automatically calculated by default settings. This study is an attempt to calibrate (not modify) this model, with the least number of possible changes, to better predict the performance of concrete targets, particularly spalling and scabbing phenomena, impacted by hard projectiles. It is shown that the present calibration of the Riedel–Hiermaier–Thoma material model performed well when compared to the default settings currently available in the model.

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Ding, Yu Qing, Wen Hui Tang, Xian Wen Ran i Xin Xu. "Numerical Simulation of Small-Scale Explosion in Dry Sand". Advanced Materials Research 705 (czerwiec 2013): 110–14. http://dx.doi.org/10.4028/www.scientific.net/amr.705.110.

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Numerical simulation of small-scale explosion in dry sand using two sand material models including the Sand model and the LA model were carried out in the present study. Three cases were considered which the depths of burial (DOB) of the explosive C4 charge were 0, 30 mm and 80 mm, respectively. The time arrival of the blast-wave front and the maximum overpressure of fixed measuring locations were studied using a two dimensional axisymmetric model in hydrocode ANSYS/AUTODYN. Furthermore, the crater diameters and the heights of detonation product cloud respect to the time were also studied by comparing with the test data. The simulation results indicate that the both sand material models were hardly predict the test data exactly which proves that the sand properties and the material model should be more carefully studied and defined.

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Ma, Chuanlin, Xudong Lu, Xi Lu i Fengjun Yin. "Damage Rule of Marine Isolator under Secondary Shock Vibration". Journal of Physics: Conference Series 2528, nr 1 (1.07.2023): 012027. http://dx.doi.org/10.1088/1742-6596/2528/1/012027.

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Abstract To study the damage of the shock vibration generated by the ship hull to the internal equipment of the ship under the secondary explosion impact, a three-dimensional simulation model of the BE rubber isolator was established. The signal of the impact vibration load was loaded by the AUTODYN software. And the relationship between the damage of the isolator under the primary vibration impact and the frequency, amplitude, and attenuation of the loading signal was found. It is revealed that the damage law curve of the isolator under the secondary shock vibration conforms to a rational function. Based on this discovery, a mathematical model of the secondary shock vibration signal that can predict the isolator damage through the primary shock vibration is established.

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Wang, Y. Z., i K. Chen. "Hypersonic target interception based on short-range damage estimation". Journal of Physics: Conference Series 2478, nr 10 (1.06.2023): 102007. http://dx.doi.org/10.1088/1742-6596/2478/10/102007.

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Abstract Aiming at the interception problem of hypersonic target end phase, the flight interception simulation based on semi-active radar guidance is firstly established, and a warhead based on fragment damage is designed. Secondly, research proposes an effective method of target damage and verifies the interception effect by simulation. AUTODYN was used to establish the 3D finite element model based on the nonlinear flight dynamics model, to simulate the damage process and fragmentation dispersion. In this paper, the probability of success of missile interception is estimated by using conditional probability and the distribution of fragment field combined with the miss distance in the interception process and the fragment explosive dispersion law of the steel ball, so as to ensure the destruction of the terminal hypersonic incoming weapon within the safe range.

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Lashko, Ye, O. Chencheva, S. Sukach, S. Shlyk, S. Gerashchenko i V. Diachenko. "APPLICATION OF THE TECHNOLOGY OF IMPULSE PROCESSING OF METALS FOR ARMOR PROTECTION OF SPECIALIZED VEHICLES". Naukovyi visnyk Donetskoho natsionalnoho tekhnichnoho universytetu, nr 1-2 (2022): 73–85. http://dx.doi.org/10.31474/2415-7902-2022-1(8)-2(9)-73-85.

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Purpose. Increasing the technical and economic indicators of the technology of impulse processing of metals and means of their diagnostics based on the development of the theoretical foundations of shape change under the impulse impact and the calculation of power parameters. Methodology. Numerical simulation of explosive loading of a plate made of Quardian 500 steel was performed in the Ansys AUTODYN system using a description of the properties of the material subjected to impulse impact and an iterative procedure. The calculation system included atmospheric air, an explosive charge (9.9 kg of trinitrotoluene), a striker plate, a test plate and soil. Results. An experimental study of the dynamic explosive load of Quardian 500 steel has been carried out and the results have been compared with the analytical calculations obtained in the Ansys AUTODYN system using the developed iterative procedure. Adequacy of the developed mathematical model of the numerical study of the explosive load to the results of the natural experiment has been determined. Scientific novelty. The solution of this problem can be used in the future to evaluate the plastic properties of materials during welding and explosion hardening, as well as during explosion stamping of blanks and the combination of welding and explosion stamping operations; with impulse stamping methods - magnetic-pulse, electro-hydraulic, gas detonation, etc., when part of the workpiece collides with the matrix, and the other part continues to deform; when stamping on hammers; when crushing materials by the impact of a rigid body; explosion fragmentation of multicomponent environments and determination of ballistic resistance of elements of combat and special equipment. Scientific significance. The developed mathematical model can be used to evaluate the protection of machine crews and increase the level of tactical and technical characteristics during demining.

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Pei, Shan Bao, i Rong Zhong Liu. "Research on Air-Structure Coupling Characteristics of Sounding Board". Advanced Materials Research 308-310 (sierpień 2011): 1074–79. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.1074.

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According to the characteristics of the shape of sounding board, the structure is immersed in gunpowder pulsation flow, the virtual mass method can be used to research on sounding board. The 3-dimensional element is used to discretize the sounding board and its surrounding air, the gas is coupled with the structure directly by the gas mass matrix. The coupling motion equation model of the sounding board and its surrounding air can be derived.The coupling modal of the sounding board system is calculated by using the software of ansys, and the data of gunpowder explosion pressure pulsation is obtained from the calculation in autodyn, then the frequency and modal of the sounding board system were further analyzed in the software of ansys. The results show that there are some significant changes in the frequency and modal of the sounding board system under the condition of prestress as well as the air-structure coupling of gunpowder pulsation fluid flow.

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Liu, Hua Ning, Yu Zheng, Jian Bo Liu i Wen Bin Li. "The Effect of Tube Materials on Metal Jet Initiating the Confined Composition B". Advanced Materials Research 1014 (lipiec 2014): 175–79. http://dx.doi.org/10.4028/www.scientific.net/amr.1014.175.

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The implementation and validation of a numerical model of the confined Composition B initiated by a metal jet has been studied by AUTODYN-2D. Two different tube thicknesses were used representing strong and weak confinement initiating system. In another contrast, various materials such as Nylon, St45 and Tungsten alloy were adopted to investigate the influence of tube yield stress on the confined explosives initiation behaviour. The results show that, in both cases, the confined explosive is always more likely to be initiated than bare explosive, and the explosive initiation probability increases with the tube thickness and yield stress. The run to detonation generally increases with the increasing lateral confining strength, but decreasing jet tip velocity.

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Liu, Xue, i Qing Ming Zhang. "Numerical Study on Characteristics Shock Initiation of Double-Shell Charges by Hypervelocity Impact". Advanced Materials Research 284-286 (lipiec 2011): 2049–52. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.2049.

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Response of shock initiation of cast TNT charges with double-shell casing impacted by hypervelocity fragment was studied using the non-linear dynamics software AUTODYN. The purpose of the study is to gain insight into the physical phenomena underlying debris cloud impacts, and to develop an equation that predicts critical fragment velocity at which a fragment must travel to cause initiation. First, strength model, reaction rate equation and equation of state of materials are briefly described. Second, the threshold law of shock-induced initiation of cast TNT with double-shell casings was obtained by analyzing pressure of the growth process. Final, the threshold shock initiation velocity of the fragment is calculated under different fragment diameter. Based upon above data we modified empirical Jacobs-Roslund model, which is very helpful to guide the safety study on shell charges structure.

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Bogosian, David, i Bence Gerber. "Analytical Predictions of Fragment Penetration through Hollow Concrete Masonry Units". Shock and Vibration 15, nr 1 (2008): 61–70. http://dx.doi.org/10.1155/2008/586876.

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Modeling steel casing fragment impacts on hollow CMU poses some problems, since the fragments will typically penetrate through the front face and may also penetrate the back face. Techniques are needed for predicting (a) the size of the hole created by the penetration, (b) the size of the annular region of damaged concrete around the hole, and (c) the residual velocity of the fragment. A series of calculations using the AUTODYN code were performed to investigate the accuracy and reliability of the model. The model uses the smooth particle hydrodynamics (SPH) approach to represent the CMU. A variety of steel fragment sizes were projected at a layer of CMU, and the resulting hole size, damage, and fragment residual velocity were tabulated. Results were validated against existing empirical relationships to insure the model's applicability, while additional analyses demonstrated trends and parametric sensitivity.

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Muthusamy, S., i A. Arulmurugu. "Computational of Orthogonal Metal Cutting Process Using Smooth Particle Hydrodynamics". Applied Mechanics and Materials 867 (lipiec 2017): 119–26. http://dx.doi.org/10.4028/www.scientific.net/amm.867.119.

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In modern years, simulating metal cutting process used in Finite element method (FEM). The cutting force is used to identify the excessive friction of machining interface and worn out tool. Optimization of machining parameters are used to maintain the precision of the component, power consumption minimized and tool wear reduced. The current project presents the simulated Finite Element SPH Model used for predict the cutting force and associate with experimental confirmation while turning the AA2219-TiB2/ZrB2 metal matrix composites (MMC). Smooth Particle Hydrodynamics (SPH) machining simulation was carried out using a Lagrangian finite element based machining model to predict the cutting force. The turning simulation operation carried out using ANSYS AUTODYN (SPH) software. Machining parameters are cutting speed, feed rate and depth of cut. The results predicted from the SPH analysis virtually close to the results attained from the experimental work. Simulation of machining test using SPH model is preferred over actual cutting test because of it reduce cost and time.

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Toy, Ahmet Tuğrul, i Barış Sevim. "Structural response of multi-story building subjected to blast load". Journal of Structural Engineering & Applied Mechanics 5, nr 1 (31.03.2022): 13–21. http://dx.doi.org/10.31462/jseam.2022.01013021.

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This paper aims to present blasting effects on the structural response of a 5-story building considering its columns, shear walls, beams, slabs, raft foundation, masonry walls, and windows. A building with a geometry of 12×20 m in plan and a height of 15.5 m is considered. The three-dimensional finite element model of the building is constituted using ANSYS Workbench and blasting analysis is explicitly performed in ANSYS AUTODYN. TNT is exploded to give blasting effects on the structure. The duration of the explosion is set to 3-msec. Stresses, displacements, material status, and pressures due to blasting on some gauge points are presented. It is seen from the study that the blast causes local damage to the load-bearing elements.

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Yang, Li, Qian Li Zhao, Xiao Dong Chai i Xiao Ying Ma. "Research on the Regular between Concentration of Superfine Powder Extinguishing Agent Explosion Scatter and Fire-Extinguishing Ability". Advanced Materials Research 887-888 (luty 2014): 1017–23. http://dx.doi.org/10.4028/www.scientific.net/amr.887-888.1017.

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In order to improve high-rise fire-extinguishing efficiency and reduce fire-extinguishing cost, a mathematical model of explosion and dispersion of extinguishing agent was built by using AUTODYN on the basis of isentropic expansion law of detonation outcome and theory of hydrodynamics to simulate the dispensing process of high-rise superfine powder fire-extinguishing agent. Different locations on the high-rise fire-extinguishing bomb were selected to be Gauss points and then were analyzed, all calculating results were contrasted finally. A method used for evaluating fire-extinguishing efficiency of fire-extinguishing bomb was put forward according to the analysis of agent concentration of different moment that it was dispensed, which was referentially meaningful to study the extinguishing efficiency of extinguishing agent.

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Li, Gang, Li Da Zhu, Jian Yu Yang i Wan Shan Wang. "Numerical Simulation of Rock Fragmentation Process for TBM Cutters Based on Three-Dimensional Dynamic Fracturing Method". Advanced Materials Research 472-475 (luty 2012): 2033–36. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.2033.

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The rock breakage process is the interaction process between TBM and rock mass, which is affected by TBM specifications, such as thrust force, cutter tip width and profile, cutter spacing, RPM, and torque, and rock mass properties mainly including rock material strength, rock brittleness, joint spacing and orientation. In this study, based on the systematic study of the existed rock constitutive model achievements and introduction of rock breaking mechanism, main failure mode of rock in the breaking process of disc cutter is added and revised in order to meet the actual situation. The method of establishing finite element model of disc cutter breaking process using ANSYS AUTODYN-3D software is introduced. After the dynamic simulation, we can obtain that geotechnical interface disturbance insulted by disc cutter. Based on plenty of experiments, it confirms reliability of numerical methods and provides a method to study cutting performance for different geological conditions.

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COSTA NETO, M. L., i G. N. DOZ. "A numerical analysis of a concrete slab breaching using high explosives". Revista IBRACON de Estruturas e Materiais 12, nr 1 (luty 2019): 122–38. http://dx.doi.org/10.1590/s1983-41952019000100010.

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Abstract Explosive breaching of walls, demolition of buildings with high structural robustness and non-programmed explosions may be extremely dangerous, the high risk of these events demands continuous researches to support the development of optimized constructive techniques and design. In this context, this work presents a numerical study of the explosive breaching of concrete wall using an optimized contact explosive charge with cilindrical shape, the CFD software Autodyn ® Ansys was used. The results were evaluated in terms of damage pattern of the concrete slab, where was considered the cratering dimensions, the breakthrough hole and concrete spalling. A significant gain of the destructive potential of the explosive was observed by the simple rearrangement of its dimensions when compared to the base model, also the robustness of software to model and simulate a complex experiment that involves the detonation of a contact explosive charge was verified.

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Mamatha, T. G., A. Patnaik, S. Biswas i P. Kumar. "Finite element modelling and development of SiC-filled ZA-27 alloy composites in erosive wear environment: a comparative analysis". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 225, nr 11 (19.09.2011): 1106–20. http://dx.doi.org/10.1177/1350650111412706.

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The erosion wear resistance of silicon carbide (SiC) filled Zn–Al alloys is determined insolid particle erosive wear test rig under five different operation conditions such as impact velocity, SiC content, erodent temperature, impingement angle, and erodent size. This study evaluates the influence of independent parameters on erosive wear behaviour of composites. A design of experiments L16 orthogonal array design is conducted in a controlled way and a regression model is developed in order to verify the experimental results. This article tries to develop finite element simulation model (ANSYS/AUTODYN) to validate the experimental results. The results obtained in this study enable the influence and significance of various parameters to be better understood. It is observed SiC-reinforced ZA-27 alloy composites exhibit better erosion resistance as compared with ZA-27 alloy composite. In this investigation, the physical and mechanical properties of all the filled and unfilled composites are also evaluated for structural applications.

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Jin, Wen, JianBin Men, JianWei Jiang i HaiFeng Li. "Study on Impact Response of Typical Powder in Confined Space". Journal of Physics: Conference Series 2478, nr 7 (1.06.2023): 072061. http://dx.doi.org/10.1088/1742-6596/2478/7/072061.

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Abstract A novel experiment combined with simulation method was developed to investigate the impact response of the powder which was put into a submunition. The powder’s material model parameter was determined by powder mechanical test. Machete hammer test platform was built to apply 20kG~30kG load to the submunition. The submunition was recycled and the powder state was observed after impacting by the Machete hammer. What’s more, nonlinear dynamics analysis software (AUTODYN) was applied to clarify the impact response and density distribution process of the powder. A verified ideal model was carried out to simulate the explosive impact loading process of the submunition. The powder density distribution was reconstructed by MATLAB. Meanwhile, a law of the powder’s centroid with the over loading was successfully established based on the simulation data. The results shows that the peak value of the impact loading has a linear relationship with the relative offset of the centroid position.

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Zhao, Xiao Xu, i Ya Dong Gong. "Research on the Load on Cutter Head of Hard Rock Tunnel Boring Machine". Applied Mechanics and Materials 684 (październik 2014): 303–7. http://dx.doi.org/10.4028/www.scientific.net/amm.684.303.

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Study on the load exerted on cutter head is very useful for the design and performance prediction of hard rock tunnel boring machines. A composite model based on smoothed particle hydrodynamics and finite element method was carried out using AUTODYN software to study the rock fragmentation mechanism of constant cross-section disk cutters in cutter head. The normal force, rolling force and side force on the disk cutters with different cutter radius were researched in the numerical simulation study. The results were verified by historical literature data. To obtain the distribution of the forces with different cutter radius, the loading of cutter head of a Ф5.75 hard rock tunnel boring machine were analyzed. The result shows that it is useful for cutter head’s design and its layout optimization.

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Zhao, Guangming, Chongyan Liu, Cheng Pan i Xiangrui Meng. "Researches on Crack Propagation of the Two Filled Noncoalescent Coplanar Flaws under the High Strain Rate Loading by means of AUTODYN-Based Simulation". Geofluids 2020 (24.11.2020): 1–10. http://dx.doi.org/10.1155/2020/8875734.

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To study the influence of fillings on rock failure. By turning to the Drucker-Prager strength model and cumulative damage criteria, investigations are made, with the nonlinear AUTODYN software, into crack propagation behaviors in crack-filled and unfilled specimens under uniaxial dynamic loading. Under investigations are crack initiation position, sequence and angle, and coalescence mode. According to the mode of propagation and coalescence, cracks are divided into three types, i.e., the tensile wing, the antiwing, and the horsetail. The simulation results show that under uniaxial dynamic loading, differences are found in initiation position, angle, and coalescence mode for specimens with cracks filled or otherwise. However, filling does not affect crack initiation sequence. Under the same loading, the damage to filled specimen is less severe than that to the unfilled specimen.

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Huang, Jun Qing, Wei Zhang, Xue Hui Yang i Wen Yue Wang. "Techniques of Fragment Numerical Simulation of Armour-Piercing Warhead Penetrating Target Process Base on AUTODYN". Advanced Materials Research 466-467 (luty 2012): 834–38. http://dx.doi.org/10.4028/www.scientific.net/amr.466-467.834.

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Needing to analyse fragment’s destructive effect for military researching purpose, it is produced after armour-piercing warhead penetrate target. How to reduce physical test expense and acquire believable researching result at the same time have been puzzled problems that must be solved as soon as possible. Discussing techniques of fragment produced in armour-piercing warhead penetration process with the way of numerical simulation based on AUTODYN, it is a program that analyses dynamics in this paper. Techniques mainly include the Lagrange, the SPH, the Lagrange combining with the SPH and the Lagrange combining with restriction invalidation, at the same time, analysed different technique’s merit and demerit by establishing the numeric simulation model of armour-piercing warhead destroying target and obtaining simulation result. By researching the technique of making numeric fragment, establishing favorable base for researching armour-piercing warhead destroying mechanism.

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Grujicic, M., B. Pandurangan, J. D. Summers, B. A. Cheeseman, W. N. Roy i R. R. Skaggs. "Application of the Modified Compaction Material Model to the Analysis of Landmine Detonation in Soil with Various Degrees of Water Saturation". Shock and Vibration 15, nr 1 (2008): 79–99. http://dx.doi.org/10.1155/2008/765494.

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A series of transient non-linear dynamics computational analyses of the explosion phenomena accompanying the detonation of a 100g C4 mine buried in sand to different depths is carried out using the software package AUTODYN. The mechanical response of sand under high deformation-rate conditions has been represented using the modified compaction material model developed in our recent work [1]. While the mechanical response of the other attendant materials (air, gaseous-detonation products and AISI 1006 mild steel) is accounted for using the material models available in literature. The results obtained (specifically, the temporal evolution of the sand overburden shape and pressure at various locations in air above the detonation site) were compared with their experimental counterparts for a (50wt%-sand/50wt.%-clay) soil obtained recently by Foedinger [2]. The comparison revealed that the modified compaction material model for sand can account reasonably well for the magnitude, spatial distribution and the temporal evolution of the dynamic loads accompanying detonation of shallow-buried mines in soils with various clay and water contents.

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Taha, Ahmed K., Zhengguo Gao i Dahai Huang. "The Numerical Investigation of Aluminum Foam-protected Reinforced Concrete Slabs under Blast Loading Using AUTODYN-3D". MATEC Web of Conferences 206 (2018): 01014. http://dx.doi.org/10.1051/matecconf/201820601014.

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Aluminum foam is a lightweight material with high energy absorption capacity. In this study A Nonlinear three-dimensional hydrocode numerical simulation was carried out using autodyn-3d, which is an extensive code dealing with explosion problems. In this simulation, a high explosive material (comp B) is blasted against several concrete panels. The model was first validated using experimental tests carried out by Chengqing and has shown good results. Several numerical tests were carried out to study two parameters that affect the deflection of reinforced concrete panels. The parameters included are the thickness of concrete target and the thickness of steel plate. The results showed that increasing the thickness of the steel plate has an insignificant effect on the deflection of the reinforced concrete target while increasing the thickness of the concrete panel has a significant effect on the deflection of the concrete target.

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Han, Jing, Hua Wang i Zhi Fei Wang. "Numerical Simulations of SFRC Projectile Penetrating into Limestone Using FEM/SPH Coupling Method". Applied Mechanics and Materials 217-219 (listopad 2012): 51–54. http://dx.doi.org/10.4028/www.scientific.net/amm.217-219.51.

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The method of using efficient inert projectile with highly efficient propulsion has great potential for the rapid and efficient excavation of rocks and ore in both surface and underground. In this paper, a series of numerical experiments were performed to simulate rock fragmentation resulted from steel fiber reinforced concrete (SFRC) projectile by using hydrodynamic finite element code AUTODYN. The fully coupled method was been adopted, in which the limestone, molded using Lagrangian mesh, is coupled to SFRC projectile molded using smoothed particle hydrodynamics (SPH) method. The numerical model was verified by comparing the simulation results with the field experiment data. Furthermore, the effect factors of geometric parameters of SFRC projectile and fibers content on the muck production were also discussed. The results of this study suggest that numerical simulation could be substituted for field experiment used for performance assessment of SFRC projectile.

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Taha, Ahmed K., Zhengguo Gao, Dahai Huang i M. S. Zahran. "Numerical investigation of a new structural configuration of a concrete barrier wall under the effect of blast loads". International Journal of Advanced Structural Engineering 11, S1 (28.11.2019): 19–34. http://dx.doi.org/10.1007/s40091-019-00252-8.

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AbstractIn this study, a non-linear three-dimensional hydrocode numerical simulation was carried out using AUTODYN-3D, which is an extensive code dealing with explosion problems. A high explosive material (comp-B) is blasted against several concrete wall barriers. The model was first validated using referenced experimental tests and has shown good results. Several numerical models were carried out to study the effect of changing the shape of wall barrier from flat to convex curve and concave curve, and also investigated the effect of changing the angle of curvature. The results showed that changing the shape of a wall barrier from flat to convex curve has the best performance in mitigating the effect of blast waves. It is also concluded that convex walls with 60° angle of curvature have the best performance compared to other barrier walls.

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Wang, Haifu, Jianguang Xiao, Yuanfeng Zheng i Qingbo Yu. "Failure and Ejection Behavior of Concrete Materials under Internal Blast". Shock and Vibration 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/8409532.

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In order to investigate the failure and ejection behavior of concrete materials under internal blast, the default Riedel-Hiermaier-Thoma (RHT) concrete model in AUTODYN and a meshfree processor called SPH are employed in this numerical simulation. It is shown that the failure mechanisms are significantly different in these damaged zones. Crushed zone is caused by shear failure while fractured zone is induced by tensile failure, and spalled zone is formed by a combination of shear and tensile failure. In addition, the ejection velocity distribution of the fragmented concrete mass on free surface is examined. The results indicate that the ejection velocity declines monotonously with the increase of the distance to symmetry axis of computational model. On the wall of the prefabricated borehole, two types of fragmented concrete mass are analyzed, and bottom initiation is recommended to eject the fragmented concrete mass effectively. Moreover, an algorithm of average ejection speed is developed to effectively estimate the drill capacity of high velocity, energetic (HE) projectiles. At last, the validity of numerical simulation is verified by physical experiments.

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Bohanek, Vječislav, Barbara Štimac Tumara, Chan Hay Yee Serene i Muhamed Sućeska. "Shock Initiation and Propagation of Detonation in ANFO". Energies 16, nr 4 (9.02.2023): 1744. http://dx.doi.org/10.3390/en16041744.

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The ammonium nitrate (AN) and fuel oil (FO) mixture known as ANFO is a typical representative of non-ideal explosives. In contrast to ideal explosives, the detonation behavior of ANFO exhibits a strong dependence on charge diameter, existence, and properties of confinement, with a large failure diameter and long distance required to establish steady-state detonation. In this study shock initiation and propagation of detonation in ANFO were studied experimentally by determining the detonation velocity at different distances from the initiation point, as well as by numerical modeling using AUTODYN hydrodynamics code and a Wood–Kirkwood detonation model incorporated into EXPLO5 thermochemical code. The run-to-steady-state detonation velocity distance was determined as a function of charge diameter, booster charge mass, and confinement. It was demonstrated that a Lee–Tarver ignition and growth reactive flow model with properly calibrated rate constants was capable of correctly ascertaining experimentally observed shock initiation behavior and propagation of detonation in ANFO, as well as the effects of charge diameter, booster mass, and confinement.

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Xie, Zhi-yuan, Yan-xin Wang, Rui-ze Xu i Jian-guang Xiao. "Research on ignition and reaction characteristic of PTFE-based reactive materials". Journal of Physics: Conference Series 2478, nr 3 (1.06.2023): 032094. http://dx.doi.org/10.1088/1742-6596/2478/3/032094.

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Abstract In order to study the ignition characteristic of PTFE-based reactive materials (RMs), Al/W/PTFE RMs with different W powder contents were prepared and split Hopkinson pressure bar (SHPB) test was carried out under different loading conditions. The temperature rise of three RMs were calculated theoretically. The material model parameters of the three formulations were calculated by using the mixture equation of state theory and Johnson-cook model, and the impact process was numerically simulated by using AUTODYN dynamics software. The results showed that the Al/PTFE (26.5/73.5) formula material has ignition reaction when the impact speed is 27.47m/s, and Al/W/PTFE (7.94/45.33/46.73) formula material is 28.68m/s. Al/W/PTFE (5.29/80/14.71) only has weak ignition reaction under experimental conditions. The ignition reaction of RMs is related to the impact temperature rise. Under the impact condition, local high temperature induced ignition occurred at the crack of RMs.With the increase of W powder content, the overall temperature rise of RMs decreased, and the reaction degree of RMs decreased.

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Abebe, Solomon, i Tesfaye Alemu Mohammed. "Performance Assessment of Reinforced Concrete Frame under Close-In Blast Loading". Advances in Civil Engineering 2022 (27.03.2022): 1–24. http://dx.doi.org/10.1155/2022/3979195.

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The need for assessing and retrofitting structures increased with time as terrorism-induced explosion trends rose with time. This paper presents a numerical investigation on performance assessment of a two-story, one-bay seismic resistant reinforced concrete framed building under close-in blast loading. ANSYS AUTODYN, an explicit nonlinear finite element software program, was used for 3D model development and analysis. The experimental results reported in the literature were used to validate proposed FE models. Furthermore, parametric studies on close-in explosive story-to-story locations and charge masses were performed on both conventional and seismically detailed RC framed structures. FEA results showed that a decrease in scaled distance raised effective plastic strain and damage index values. Furthermore, simultaneous use of close-spaced transverse steel reinforcement spacing in mid-height and ends of reinforced concrete columns is found to be effective in reducing both effective plastic strains and damage index values.

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Langdon, Geneive, Gerald Nurick, Neil Du Plessis i Ian Rossiter. "Using Perforated Plates as a Blast Wave Shielding Technique for Application to Tunnels". Applied Mechanics and Materials 82 (lipiec 2011): 467–72. http://dx.doi.org/10.4028/www.scientific.net/amm.82.467.

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Tunnels are vulnerable to devastating explosions, due to the concentration of explosive energy that would be many times greater than in an unconfined blast. One way to mitigate the damage resulting from an explosion is to disrupt the blast wave as it propagates along a tunnel. This paper presents the results of an investigation into the performance of perforated plates as a blast wave mitigation method in tunnel-like structures. Plastic explosive was detonated at the open end of a small-scale rigid steel tube and the blast wave propagated down the tube towards a thin, steel target plate. Increasing the separation distance between the perforated plate and target plate decreased the target plate deformation and increased the impulse at which tearing initiated. Large plastic displacement of the perforated plates was observed. Ansys Autodyn was used to model the experiments and provide additional insight into the blast wave propagation.

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Pană, Iuliana Florina, Luminiţa Cristina Alil i Florin Ilie. "Aspects Regarding Shock Wave Mitigation Through Different Media". Scientific Bulletin 20, nr 2 (1.12.2015): 49–54. http://dx.doi.org/10.1515/bsaft-2015-0008.

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Abstract The main application of underwater detonation since the Second World War is to destroy military ships. Nowadays, a lot of studies are performed in order to discover a controlled and safe application of shock waves through different media. The paper presents the results of a research on a bubble curtain behaviour subjected to shock waves generated by an underwater TNT blast. The main objective was to analyze the mitigation solution of underwater explosion effects by means of gas bubbles. Simulations using ANSYS AUTODYN and explicit dynamics procedures were performed on a 3D model, in order to better understand the physical process of formation and propagation of a shock wave in the biphasic medium which represents the purpose of many researchers. The numerical simulations were performed taking into account the interaction between a shock wave and the bubble curtain considering a random distribution in space and bubble dimensions.

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Yang, Feng, Lixin Xu, Hongbo Zhai i Jianjun Su. "Numerical Simulations of Air Shock Wave Overpressure Propagation in Shallow-buried Explosion". Journal of Physics: Conference Series 2470, nr 1 (1.03.2023): 012022. http://dx.doi.org/10.1088/1742-6596/2470/1/012022.

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Abstract Shallow-buried explosion is a typical working condition of ammunition. Studying the overpressure propagation law of air shock wave in shallow-buried explosion is helpful to completely characterize the ammunition power in actual combat. In this paper, a numerical model of shallow-buried explosion of cylindrical charge based on Euler method is established in the framework of simulation software AUTODYN, which simulates the formation process of crater when cylindrical charge is initiated under the conditions of different charge amount and different buried depth, and analyzes the propagation law of explosion shock wave in the air. The following conclusions are drawn: compared with the mass of charge, the depth of burial has more influence on the surface air shock wave. According to the simulation data, the empirical formulas related to the peak overpressure of shock wave and the charge, buried depth and horizontal detonation center distance are fitted.

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Dar, Uzair Ahmed, Weihong Zhang i Yingjie Xu. "FE Analysis of Dynamic Response of Aircraft Windshield against Bird Impact". International Journal of Aerospace Engineering 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/171768.

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Bird impact poses serious threats to military and civilian aircrafts as they lead to fatal structural damage to critical aircraft components. The exposed aircraft components such as windshields, radomes, leading edges, engine structure, and blades are vulnerable to bird strikes. Windshield is the frontal part of cockpit and more susceptible to bird impact. In the present study, finite element (FE) simulations were performed to assess the dynamic response of windshield against high velocity bird impact. Numerical simulations were performed by developing nonlinear FE model in commercially available explicit FE solver AUTODYN. An elastic-plastic material model coupled with maximum principal strain failure criterion was implemented to model the impact response of windshield. Numerical model was validated with published experimental results and further employed to investigate the influence of various parameters on dynamic behavior of windshield. The parameters include the mass, shape, and velocity of bird, angle of impact, and impact location. On the basis of numerical results, the critical bird velocity and failure locations on windshield were also determined. The results show that these parameters have strong influence on impact response of windshield, and bird velocity and impact angle were amongst the most critical factors to be considered in windshield design.

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Králik, Juraj, i Michal Baran. "Numerical Analysis of the Exterior Explosion Effects on the Buildings with Barriers". Applied Mechanics and Materials 390 (sierpień 2013): 230–34. http://dx.doi.org/10.4028/www.scientific.net/amm.390.230.

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Generation and transmission of blast waves in real terrains is of major importance for risk analysis procedures involving accidental explosion scenarios. This paper aims to show the approach to addressing air pressure waves from explosions using empirical formulas and compare them with numerical computations, which is solved using the computational program AUTODYN. Simulation of a simple model of the building is presented in the interaction with the air pressure wave caused by the explosion, which is initiated at a distance of 30 meters from the front of the building. The explosion process will be shown in 2D axial plane which is then remapped into Eulerian multi-material 3D space using the interaction of the rigid obstacles. The weight of 1000 kg TNT charge is used, which is located one meter above the ground and represents the explosive placed in a car in accordance with FEMA requirements. The effects of the protection structures are investigated.

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FIKUS, Bartosz. "Preliminary Numerical Estimation of Selected Terminal Ballistic Effects Produced by Explosion of Mortar Projectile". Problems of Mechatronics Armament Aviation Safety Engineering 9, nr 1 (31.03.2018): 49–60. http://dx.doi.org/10.5604/01.3001.0011.7178.

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Results of theoretical modelling of mortar projectile’s fragments propulsion were shown. Taking into account universality of application of the considered ammunition, it seems to be reasonable to conduct simulations of projectile’s fragments propulsion and interaction with the environment. In the conducted investigations, due to dynamic character of the whole phenomena, characterized by extremely high values of strains and strain’s rate, the meshless explicit approach was used (Smoothed Particle Hydrodynamics method implemented in AUTODYN software). This approach minimalized the negative effects of deformation of “classical” Lagrangian mesh. In order to validate a numerical model, the results were compared with the simplified Gurney’s formula, which provides high accuracy of fragment’s velocity for regular shapes of casing. Comparison of the results showed low value of relative discrepancy (lower than 10%) for the cylindrical part of the casing in which detonation was fully developed and resulted in higher values of relative discrepancy of initial velocity for the non – cylindrical region, especially where the detonation was not developed.

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Kojima, Tomohisa, Masahiro Suzuki i Mitsuo Notomi. "Numerical Simulation on Dynamic Fracture of Glass Plate Fitted with Polymeric Film". Advanced Materials Research 1166 (27.09.2021): 57–64. http://dx.doi.org/10.4028/www.scientific.net/amr.1166.57.

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The impact resistance improvement is important for window glass to protect people from injury. Although it has been proved that the impact resistance of a glass plate can be improved easily by fitting a thin polymeric film, its mechanism has not been clarified yet. The purpose of this study is to clarify the reinforcing mechanism of the impact resistance of a glass plate by fitting a polymeric film. To clarify it, a numerical simulation model was built using ANSYS Autodyn to simulate the dynamic fracture of a glass plate fitted with a polymeric film. The simulation model and results were examined by comparing them to the experimental result in the previous study. The Johnson-Holmquist (JH2) damage model was used for the constitutive law of the glass plate. A polymeric film with 0.2 mm thickness (3% with the glass plate) was modeled at the non-impact surface of the glass plate. The nodes of the glass plate at the interface with the film connected the nodes of the film by perfect bonding. By comparing the simulation results to the experiment, it was indicated the importance of modeling the remaining fragments of the glass plate and the adhesive layer of the film in simulating the dynamic fracture of the glass plate fitted with polymeric film.

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Liu, Ruifeng, Wenxian Wang, Tingting Zhang i Xiaodan Yuan. "Numerical study of Ti/Al/Mg three-layer plates on the interface behavior in explosive welding". Science and Engineering of Composite Materials 24, nr 6 (27.11.2017): 833–43. http://dx.doi.org/10.1515/secm-2015-0491.

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AbstractIn this study, a finite element model of the explosive welding process of three-layer plates composed of Ti/Al/Mg was established, and the interfacial behaviors of three-layer plates were researched. We investigated the influences that affect the quality of explosive bonding and explored the influence factors of variable physical parameters in the simulation. The finite difference engineering package AUTODYN with the smoothed particle hydrodynamics method has been used to model the collision in this work. The von Mises strength model was used to describe the behavior of Ti/Al/Mg composite plates. Wave morphology on the Al/Mg interface and straight morphology on the Ti/Al interface were produced in this study; meanwhile, jet phenomenon occurred obviously in the simulation process. The contours of velocity, pressure, shear stress, and effective plastic strain of Ti/Al/Mg were also discussed. The result of X-direction velocity showed a delay in time and location of collision point between the Ti/Al and the Al/Mg interface. The detonation point was the minimum pressure, and the collision point was the maximum pressure compared with other sections. The value of effective plastic strain must exceed a threshold to obtain a good bonding, and the shear stress was of opposite sign in the simulation.

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