scholarly journals Beirut explosion: TNT equivalence from the fireball evolution in the first 170 milliseconds

Shock Waves ◽  
2021 ◽  
Author(s):  
C. J. Aouad ◽  
W. Chemissany ◽  
P. Mazzali ◽  
Y. Temsah ◽  
A. Jahami
Keyword(s):  
Shock Wave ◽  
Excellent Agreement ◽  
Spherical Geometry ◽  
Stopping Distance ◽  
Tnt Equivalent ◽  
Close Range ◽  
Consecutive Time ◽  
Tnt Equivalence ◽  
Increasing Function ◽  
Instantaneous Energy

AbstractThe evolution of the fireball resulting from the August 2020 Beirut explosion is traced using amateur videos taken during the first 400 ms after the detonation. Thirty-nine frames separated by 16.66–33.33 ms are extracted from six different videos located precisely on the map. Time evolution of the shock wave radius is traced by the fireball at consecutive time moments until about $$ t \approx 170$$ t ≈ 170  ms and a distance $$ d \approx 128$$ d ≈ 128  m. Pixel scales for the videos are calibrated by de-projecting the existing grain silos building, for which accurate as-built drawings are available, using the length, the width, and the height and by defining the line-of-sight incident angles. In the distance range $$ d \approx $$ d ≈ 60–128 m from the explosion center, the evolution of the fireball follows the Sedov–Taylor model with spherical geometry and an almost instantaneous energy release. This model is used to derive the energy available to drive the shock front at early times. Additionally, a drag model is fitted to the fireball evolution until its stopping at a time $$ t \approx 500$$ t ≈ 500  ms at a distance $$d \approx 145\pm 5$$ d ≈ 145 ± 5  m. Using the derived TNT equivalent yield, the scaled stopping distance reached by the fireball and the shock wave-fireball detachment epoch within which the fireball is used to measure the shock wave are in excellent agreement with other experimental data. A total TNT equivalence of $$ 200\pm 80\,\mathrm{t}$$ 200 ± 80 t at a distance $$ d \approx 130$$ d ≈ 130  m is found. Finally, the dimensions of the crater size taken from a hydrographic survey conducted 6 days after the explosion are scaled with the known correlation equations yielding a close range of results. A recent published article by Dewey (Shock Waves 31:95–99, 2021) shows that the Beirut explosion TNT equivalence is an increasing function of distance. The results of the current paper are quantitatively in excellent agreement with this finding. These results present an argument that the actual mass of ammonium nitrate that contributed to the detonation is much less than the quantity that was officially claimed available.

Research of High-Power Underwater Explosive Based on Analysis of Underwater Energy

2013 ◽  
Vol 848 ◽  
pp. 183-187
Author(s):  
Qiu An Huang ◽  
Geng Guang Xu ◽  
Yong Jiang Wei ◽  
Xue Mei Liu
Keyword(s):  
Shock Wave ◽  
High Power ◽  
Energy Output ◽  
Underwater Shock Wave ◽  
Tnt Equivalent ◽  
Shock Wave Energy ◽  
Output Structure ◽  
Main Charge ◽  
New Type ◽  
Underwater Shock

In this paper,by researching the underwater energy output structure of explosion and improving the technical method to enhance the energy of underwater high-power explosive,a new type of underwater high-power PBX explosive was developed. This type of PBX,of which the underwater shock wave energy was 1.75 TNT equivalent and its bubble energy was 2.41 TNT equivalent,was suitable for the main charge of underwater weapon warhead and its energy archived the domestic leading level.

scholarly journals EDS Containment Vessel TNT Equivalence Testing

2017 ◽  
Author(s):  
Robert W. Crocker ◽  
Brent L. Haroldsen ◽  
Jerome H. Stofleth
Keyword(s):  
Free Volume ◽  
Pressure Vessel ◽  
Project Manager ◽  
Equivalence Testing ◽  
Phase 2 ◽  
Containment Vessel ◽  
Tnt Equivalent ◽  
Vessel Response ◽  
Tnt Equivalence ◽  
Explosive Destruction

The V26 containment vessel was procured by the Project Manager, Non-Stockpile Chemical Materiel (PMNSCM) for use on the Phase-2 Explosive Destruction Systems. It was fabricated under Code Case 2564 of the ASME Boiler and Pressure Vessel Code, which provides rules for the design of impulsively loaded vessels [1]. The explosive rating for the vessel, based on the Code Case, is nine (9) pounds TNT-equivalent for up to 637 detonations. This report documents the results of tests that were performed on the vessel at Sandia National Laboratories to qualify the vessel for explosive use [2]. Three of these explosive tests consisted of: (1) 9lbs bare charge of Composition C-4 (equivalent to 11.25lbs TNT); (2) a 7.2lbs bare charge of Composition C-4 (equivalent to 9lbs TNT); (3) a bare charge of 9lbs cast TNT. The results of these tests are compared in order to provide an understanding of how varying charge size affects vessel response when the ratio of free volume to charge volume is small, and in making direct comparisons between TNT and Composition C-4 for TNT equivalency calculations. In a previous paper [3], the 7.2lbs bare charge of Composition C-4, (2) above, was compared to 7.2lbs of Composition C-4 distributed into 6 charges.

Modeling of Boiling Liquid Expanding Vapor Explosion (BLEVE): Plane, Cylindrical and Spherical 1D Model

2008 ◽  
Author(s):  
G. A. Pinhasi ◽  
Y. Dahan ◽  
A. Dayan ◽  
A. Ullmann
Keyword(s):  
Shock Wave ◽  
Current Model ◽  
Dynamic State ◽  
Vapor Explosion ◽  
Two Phase ◽  
Boiling Liquid ◽  
Energy Models ◽  
Model Predictions ◽  
1D Model ◽  
Tnt Equivalence

A 1D plane, cylindrical and spherical numerical model was developed for estimating the thermodynamic and the dynamic state of the boiling liquid during a boiling liquid expanding vapor explosion (BLEVE) event. The model predicts, simultaneously, the flow properties of the expanding two-phase flashing mixture and its surrounding air. The possible presence of a shock wave formed by the fluid expansion through the air is accounted for in the model. Model predictions of the shock wave strengths, in terms of TNT equivalence for the various coordinate systems, were compared against those obtained by simple energy models. As expected, the simple energy models over predicts the shock wave strength. However, the simple model which accounts for the expansion irreversibility, produces results which are closer to current model predictions. For the 1D plane case the model simulates a BLEVE scenario in a tunnel, whereas for the spherical case the more realistic BLEVE scenario in free space is being studied.

scholarly journals TNT equivalent of the shock wave energy generated during the supersonic flight of an aircraft

2021 ◽  
Vol 2124 (1) ◽  
pp. 012001
Author(s):  
Ya V Drobzheva ◽  
D V Zikunkova ◽  
V M Krasnov
Keyword(s):  
Shock Wave ◽  
Wave Energy ◽  
Acoustic Pulse ◽  
Nonlinear Effects ◽  
Aircraft Design ◽  
Resistance Force ◽  
Supersonic Speed ◽  
Tnt Equivalent ◽  
Shock Wave Energy ◽  
The Impact

Abstract To assess the impact on human health of the sonic boom that occurs when an aircraft is flying at supersonic speed, and, accordingly, to solve the problem of noise reduction by optimizing the aircraft design, it is proposed to evaluate the shock wave energy using the TNT equivalent of a cylindrical explosion. An example of calculating the shock wave energy during flights of F4 and F18 aircraft at different altitudes is considered. To calculate the evolution of an acoustic pulse during its propagation from the boundary of the shock wave transition to the acoustic one, the wave equation and its solution are used, taking into account the inhomogenei-ty of the atmosphere, nonlinear effects, absorption and expansion of the wave front, as well as the results of ground-based measurements of acoustic pulses. The results of calculations of the dependence of the explosion energy on the flight altitude, as well as on the type of aircraft are explained on the basis of the formula for the atmospheric resistance force.

scholarly journals Full-Scale Experimental Verification of the Explosion Shock Wave Model of a Natural Gas Pipeline

2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
Shaohua Dong ◽  
Yinuo Chen ◽  
Xuan Sun ◽  
Hang Zhang
Keyword(s):  
Shock Wave ◽  
Natural Gas ◽  
Wave Model ◽  
Full Scale ◽  
Gas Pipeline ◽  
Operating Conditions ◽  
Natural Gas Pipeline ◽  
Tnt Equivalent ◽  
The Absolute ◽  
Shock Wave Model

As developments in natural gas pipelines increasingly incorporate higher grades of steel, larger diameters, and higher pressures, the consequences of an accident caused by leakage, explosion, or ignition become progressively more severe. Currently, major technical obstacles include the quantification of the impact of an explosion shock wave of a high-strength, large-diameter natural gas pipeline, and the selection of a reasonable shock wave overpressure model appropriate to the operating conditions. In this paper, six models of shock wave overpressure theories, namely, the TNT equivalent method, the TNO method, the multienergy method, the British Gas method, the Shell method, and the Lee formula, were compared and analyzed to determine their applicability. A shock wave model adapted to the characteristics of a full-scale test was proposed, and the model verification of a full-scale blasting test was conducted on pipelines with diameters of 1422 mm and 1219 mm, respectively. Subsequent results indicated that the modifications to the TNT equivalent and the test parameters correlated with changes in the suitability of the model. Henrych’s formula calculation model of the British Gas method was found to correspond strongly with the measured value, in which the absolute value of the relative error was less than 30% and the absolute error within the range of 78 m to 800 m was no more than 0.05 MPa. Thus, the Henrych formula was adopted as the primary model formula for the shock wave overpressure calculations in this study. To further correct the error of the model, the trend between the curve obtained by the Henrych formula and the fitting curve of the measured value was compared and analyzed. The positive and negative compensations of the shaded area before and after the intersection point were carried out, and the new error correction overpressure model formula was obtained by fitting, with the error controlled within 15%.

scholarly journals Dynamic response of aluminium sheet 2024-T3 subjected to close-range shock wave: experimental and numerical studies

2021 ◽  
Vol 10 ◽  
pp. 349-362
Author(s):  
Amin Bassiri Nia ◽  
Ali Farokhi Nejad ◽  
Li Xin ◽  
Amran Ayob ◽  
Mohd Yazid Yahya ◽  
...  
Keyword(s):  
Shock Wave ◽  
Dynamic Response ◽  
Aluminium Sheet ◽  
Numerical Studies ◽  
Close Range

Theoretical and Experimental Research on Perforation Remnant Energy

2011 ◽  
Vol 339 ◽  
pp. 379-385 ◽  
Author(s):  
Cheng Bing Li ◽  
Jin Xiong ◽  
Ming Yong Ma
Keyword(s):  
Energy Source ◽  
Shock Wave ◽  
Theoretical Analysis ◽  
Experimental Research ◽  
Energy Method ◽  
Underwater Explosion ◽  
Oil Well ◽  
Energy Equivalent ◽  
Tnt Equivalent ◽  
Explosive Charges

During the perforating and testing combination, the tubing, packer and casing are strongly impacted by shock-wave generated from oil perforators would be damaged. The energy conversion and energy equivalent theories and the underwater explosion energy method are applied to investigate the perforation remnant energy. The theoretical analysis results indicate that the explosion remnant energy of the perforators is the main energy source causing damage of the tubing, packer and casing and the explosion process of the perforators with guns in the oil well can be simplified to the explosion of ordinary explosive charges in the perforation liquid. TNT equivalent and HMX equivalent of perforation remnant energy of three type perforators are obtained by experiments and Cole Formula. Studying results can help to predict dynamic wellbore behaviors and provide a reference for designing the perforation program.

scholarly journals Application of grid convergence index to shock wave validated with LS-DYNA and ProsAir

2020 ◽  
Vol 39 (3) ◽  
pp. 20-26
Author(s):  
Ricardo Castedo ◽  
Carlos Reifarth ◽  
Anastasio P Santos ◽  
Jorge J Losada ◽  
Lina M López ◽  
...  
Keyword(s):  
Shock Wave ◽  
Solid Mechanics ◽  
Field Trials ◽  
Physical Problem ◽  
Shock Propagation ◽  
Measured Variable ◽  
Tnt Equivalent ◽  
Grid Convergence ◽  
Grid Convergence Index ◽  
Computational Solid Mechanics

The discretization error is not always calculated, even though it is essential for the studies of computational solid mechanics. However, it is well known that an error committed by the mesh used can be as large as the measured variable, which greatly invalidates the results obtained. The grid convergence index (GCI) method makes possible to determine on a solid basis, the order of convergence and the asymptotic solution. This method seems to be a suitable estimator despite further research is needed in the context of blast situations and finite element (FE) calculations. For this purpose, field trials were performed consisting in the detonation of a spherical hanging load of homemade explosive. The pressure generated by the shock wave was measured in different positions at two distances. With these data, a TNT equivalent has been obtained and used to calculate the shock propagation with the solvers LS-DYNA and ProsAir. This work aims to verify the GCI method by comparing its results with field data along with the simulations carried out. The comparison also seeks to validate the methodology used to obtain the TNT equivalent.This research shows that the GCI gives good results for both solvers despite the complexity of the physical problem. Besides, LS-DYNA displays better correlation with the experimental data than the ProsAir results, with an error of less than 10% in all values.

scholarly journals Shock-wave experiment with the Chelyabinsk LL5 meteorite: experimental parameters and the texture of the shock-affected material)

2019 ◽  
Vol 64 (8) ◽  
pp. 859-868
Author(s):  
E. V. Petrova ◽  
V. I. Grokhovsky ◽  
T. Kohout ◽  
R. F. Muftakhetdinova ◽  
G. G. Yakovlev
Keyword(s):  
Shock Wave ◽  
Spherical Geometry ◽  
Petrographic Analysis ◽  
Small Bodies ◽  
Zone Formation ◽  
Experimental Parameters ◽  
Material Texture ◽  
Shock Experiment ◽  
Shock Modeling ◽  
Shock Wave Experiment

The shock experiment with Chelyabinsk LL5 light lithology material was performed as a spherical geometry shock. The material experienced shock and thermal metamorphism from the initial S3–4 up to complete melt stage. Temperature and pressure realized were estimated above 2000°С and 90 GPa. Textural shock effects were studied by the means of optical and electron microscopy. By the only experimental impact, all the range of the shock pressures and temperatures was realized. Four zones were revealed from the petrographic analysis: 1 – melt zone, 2 – melted silicates zone, 3 – black ring zone, 4 – weakly shocked initial material. Several features of the material texture were noted: displacement of the metal and troilite phases from the central melt zone; mixed lithology zone formation (light-colored chondrules within the silicate melt); dark-colored lithology ring formation; generation of radial-oriented shock veins. Thus, at the experimental fragment, four texture zones were formed. These zones correspond to the different lithology types of the Chelyabinsk LL5 meteorite, which could be found in different fragments of the meteoritic shower from UrFU collection. The results obtained prove that the shock wave loading experiment could be used for space shock modeling. Therefore, the processes of the small bodies of the Solar system could be experimentally modeled at the laboratory conditions.

Instrumentation for detecting channelling radiation in the high-voltage electron microscope

1983 ◽  
Vol 41 ◽  
pp. 318-319
Author(s):  
J. H. Butler ◽  
C. J. Humphreys
Keyword(s):  
Monochromatic Light ◽  
Incident Beam ◽  
Laboratory Frame ◽  
Relativistic Electrons ◽  
Voltage Electron ◽  
Dipole Emission ◽  
Sinusoidal Oscillations ◽  
Pass Through ◽  
Incident Beam Energy ◽  
Increasing Function

Electromagnetic radiation is emitted when fast (relativistic) electrons pass through crystal targets which are oriented in a preferential (channelling) direction with respect to the incident beam. In the classical sense, the electrons perform sinusoidal oscillations as they propagate through the crystal (as illustrated in Fig. 1 for the case of planar channelling). When viewed in the electron rest frame, this motion, a result of successive Bragg reflections, gives rise to familiar dipole emission. In the laboratory frame, the radiation is seen to be of a higher energy (because of the Doppler shift) and is also compressed into a narrower cone of emission (due to the relativistic “searchlight” effect). The energy and yield of this monochromatic light is a continuously increasing function of the incident beam energy and, for beam energies of 1 MeV and higher, it occurs in the x-ray and γ-ray regions of the spectrum. Consequently, much interest has been expressed in regard to the use of this phenomenon as the basis for fabricating a coherent, tunable radiation source.

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