Blast Radius Research Articles

Revisiting Taylor’s analysis of the Trinity test

Abstract The atomic bomb uses fission of heavy elements to produce a large amount of energy. It was designed and deployed during World War II by the United States military. The first test of an atomic bomb occurred in July 1945 in New Mexico and was given the name Trinity; this test was not declassified until 1949. In that year, Geoffrey Ingram Taylor released two papers detailing his process in calculating the energy yield of the atomic bomb from pictures of the Trinity explosion alone. Many scientists made similar calculations concurrently, although Taylor is often accredited with them. Since then, many scientists have also attempted to calculate a yield through various methods. This paper walks through these methods with a focus on Taylor’s method—based on first principles—as well as redoing the calculations that he performed with modern tools. In this paper, we make use of state-of-the-art computer vision tools to find a more precise measurement of the blast radius, as well as using curve fitting and numerical integration methods. With more precise measurements we are able to follow in Taylor’s footstep toward a more accurate approximation.

Evacuation and shelter plans for asteroid impacts informed by hurricanes and nuclear explosions

Evacuation zone recommendations are determined for potential asteroid impacts. In most impacts on land, the dominant damage mechanism is the blast wave. Hurricane evacuations in the United States show that on average people evacuate to a 1 in a million risk of fatality level. To achieve the equivalent risk from a blast wave, preliminary estimates show that everyone within the 1–2 psi (≈0.07–0.14 atm or bar) blast radius should evacuate as, even when taking shelter, the risk threshold is probably exceeded. From there out to the 0.4–0.5 psi radii, seeking shelter in the basement of a reinforced concrete building or storm shelter, or in a home-built shelter in the basement of a house would suffice as alternatives to evacuation while keeping the fatality risk below 1 in a million. From 0.4 down to 0.1–0.2 psi, windows may break but little to no structural damage to buildings is expected, so simply staying away from windows and doors would be sufficient.

Is there a blast radius of workplace bullying? Ripple effects on witnesses and non-witnesses

Substantial evidence points to detrimental effects of workplace bullying on the health, well-being and job attitudes among those exposed. What is less known is how bullying affects their non-exposed colleagues. In this study, we introduce the concept “blast radius of bullying” and use social information processing theory to investigate how bullying impacts targets, witnesses, and non-witnesses. We suggest three mechanisms to understand the impact bullying may have on non-targets: the working environment mechanism, secondary victimization, and emotional contagion. We hypothesized that non-exposed colleagues in groups where bullying exists would feel some impact of bullying, but that it would be smaller for those further away from the point of impact. We also investigated the association between the severity of mistreatment and outcomes for the above-mentioned categories. We used data (n = 2215) from 195 work groups. The results provided evidence for a blast radius of bullying, however, not as far-reaching as hypothesized as only direct observation of mistreatment was associated with negative outcomes. The severity of mistreatment was not associated with the outcomes, whereas the frequency of observation had some impact for witnesses. The study showed that also witnesses may be regarded as “co-victims”.

The 8 January 2020 theatre ballistic missile attack on US soldiers stationed at Al Asad Air Base, Iraq: case series using a concussion subtypes framework to approach a real-world, chaotic blast-related TBI mass casualty event

ObjectivesThis study aims to describe which concussion subtype(s) result specifically from the explosions of theatre ballistic missiles (TBMs) blast waves, an extremely rare occurrence in modern warfare. We provide feedback...

Oil and Water

Fulmer Hamilton stands in a boilersuit and a hard hat wielding a flare gun. Further oil production threatens disaster on the Kinloch Bravo platform, located off the coast of Scotland in the harsh conditions of the North Sea. Following a power outage, only a manual shutdown can override the system and spare the crew from a petroleum-fueled explosion. The Scottish rig worker is bending the rules, following knowledge and intuition gained on the job. Fulmer succeeds in at least momentarily saving himself and his colleagues, but only after giving himself an easier shot by firing within the blast radius created by the shutdown.

Dasgupta's Detonation

Dasgupta's Detonation

Analysis of factors influencing infrared extinction area of explosive smokescreen

ObjectivesComparative studies of different smokescreen designs are essential to determine differences in extinction performance. This study aims to investigate the extinction performance of explosive smokescreen under different conditions, and to provide an evaluation method for the optimal design of its charge structure. MethodsThe process of formation of the smokescreen with a cylindrical charge structure is described based on the smoothed particle hydrodynamics method. The blast radius and particle density distribution of the smokescreen were calculated for different charge structures and charge ratios through simulations. Lambert–Beer's law was combined to obtain the infrared extinction area. An analysis was then conducted to determine the influence of the number of baffles in the charge structure and charge ratio on the extinction performance of the smokescreen. Field tests were conducted to verify the simulation results. ResultsIncreasing the number of baffles in the projectile structure made the particle distribution of the smokescreen more uniform and resulted in a larger infrared extinction area. An increase in the explosive quantity, made the smokescreen more dispersed. However, too much of the explosives caused the smokescreen to be sparse, reducing the infrared extinction area.

Attenuation of blast waves from an intense explosion in dusty gases: a case study

An intense explosion in dusty gas is analyzed considering the Beirut ammonium nitrate explosion of 2020 as a case study. The data available from various sources for the Beirut explosion are used to determine the energy released and the possible reduction in damage radius if there were additional dust particles in the atmosphere. The relationship derived in our previous article ( Proc. R. Soc. A 476 , 2020) between the blast radius and the time of arrival of the shock seems quite accurate, and here the energy released by the explosion and the mass of trinitrotoluene (TNT) equivalent based on energy considerations and blast damage are estimated for dusty gases. These estimates depend on Γ , the ratio of specific heats of the dusty gas mixture. The hydrostatic overpressure and dynamic pressure are calculated from previous results by using the data available. The variation of the three dust parameters in the atmosphere, i.e. (i) mass concentration of dust particles ( k p ) , (ii) specific heat ratio ( β ) , and (iii) density ratio ( G ) , gives the estimated TNT equivalence as ≈ 0.1 kt to 2.5 kt up to a distance of 500 m. Enhanced decay and reduced pressure is evident for dusty gases with appropriate dust parameters.

Conceptual Design of a Reusable Submunition Dispenser for Unmanned Aerial Vehicles

The paper describes a concept for developing a dedicated combat asset for performing effective fragmentation attack on surface targets and having dimensions and weight suited to being carried by an unmanned aerial vehicle (UAV) with a maximum payload of 150 kg. The designed combat asset, i.e. cluster bomblets ejected from a reusable submunition dispenser, will be intended for destroying enemy personnel, unarmoured ground targets, lightly armoured equipment, ground support equipment, and aircraft and field ammunition depots. The introduction of the paper analyzed the existing submunition dispenser and cluster bomblet solutions. The key aspects of the paper include the calculation of the effective blast radius of the designed cluster bomblet and the analysis of the trajectory of a bomb dropped from horizontal flight. A bombing analysis was carried out, taking into account the influence of the atmosphere and drop control conditions on bombing accuracy and proper fragment coverage of the bombed area. A preliminary concept of the airdrop control system was developed, which could enable effective bombing with a series of cluster bomblets. As part of the work, element models and CAD assembly models of the dispenser and cluster bomblet structures were fabricated.

186 Thyroid Monitoring for Patients Born After the Chernobyl Disaster Within the Blast Radius: A Literature Review

Abstract Aim There is a well-documented increase in incidence of thyroid cancer in individuals living within the blast radius at the time of the Chernobyl nuclear disaster. Following a case encountered in our clinical practice of a patient born within the blast radius but after the blast itself, we aimed to evaluate the evidence of increased thyroid cancer within such a cohort. Method We reviewed the existing literature for evidence for or against an increase in thyroid cancer in this population group. Identified articles were reviewed and appraised, evaluating the evidence for any possible increase in incidence. Results Very few papers looked at risk in such a population, but those identified suggested no increase in risk of thyroid cancer in individuals born within the radius, after the blast. Conclusions We conclude there is little evidence supporting routine monitoring for individuals born within the blast radius after the blast, and as such this should be included in the British Thyroid Association guidelines.

Research on Dynamic Response of Slopes With Weak Interlayers Under Mining Blasting Vibration

As blasting technology starts to be used in a wide range of areas, blast loading has led to an increasing number of geological disasters such as slope deformation, collapses, and soil slippage. Slopes with weak interlayers are more likely to be deformed and damaged under the influence of blast loading. It is of great importance to study the evolution for the deformation of slopes with weak interlayers during blasting excavation. This study constructed a slope model with a weak interlayer to investigate the influence of different factors of blasting, including explosive charge, blast radius, blast origin, and multi-hole blasting, on the internal dynamic response. The deformation mechanism of slopes with weak interlayers under the influence of blast loading was analyzed. Test results show that each layer of the model had a different displacement response (uncoordinated dynamic response) to blasting with various factors. Explosive energy and the pattern of dynamic response of each layer varied depending on different settings of blasting factors such as explosive charge, blast radius, blast origin, and detonation initiation method. When the explosive energy produced under the influence of various factors was small, the change in the uncoordinated dynamic response between layers was significant, and the change gradually became less significant as the explosive energy increased. Therefore, this study has proposed the concept of critical explosive energy, and it is speculated that when the explosive energy produced with various factors is less than critical explosive energy, the dynamic response is mainly affected by the internal structure of the slope (property difference induced geologic layers). In other words, the uncoordinated motion of material’s particles in each layer is caused by different limitations and the degree of movement of the particles, which leads to the uncoordinated dynamic response and uncoordinated deformation of each layer. If the explosive energy is greater than the critical value, the dynamic response of each layer is mainly affected by the explosive energy. The differences in the internal structure of the slope are negligible, and the incoordination of dynamic responses between layers gradually weakens and tends to synchronize.

Urban security of urban objects affected as a result of terrorist attacks

This study examines the development of an optimal urban planning methodology that ensures the safety of buildings and structures in residential areas affected by hostilities in Syrian cities as part of the recovery and reconstruction process to minimize the loss of urban property and population in the event of a recurrence of such hostilities in the future. The study is based on the urban planning methodology developed by the author to assess the destruction of residential areas and is considered its continuation, which allows determining the degree of destruction of residential areas in the radius of the source of destruction by the excessive pressure of a blast wave and the explosives used. The principles of safest urban planning were determined by analyzing and comparing urban planning models and determining the optimal distance between buildings by defining the blast radius and the safest distance at which buildings can be located.

Local, Regional and Transnational Queer-feminist Arab, Muslim, and People of Color Insurgent-Abolitionist Horizons

How can radical queer-feminist contestations of the longstanding disciplining and punishment of women, trans peoples, and gender dissidents elucidate the blast radius of the multiple, dynamic, intersectional ‘cages’ that define the daily conditions of racialized gendered-queer life that require obliterating? I examine the notion of capitalist and authoritarian nation-state ‘cages’ that punitively condemns racialized queer-feminist lives in the decolonial context of gender-based sexual harassment in Egypt and the inspiring autonomous and lateral anti-authoritarian and anti-capitalist initiative that some of my queer-feminist Egyptian and Muslim fieldwork participants incepted to combat harassment in an ongoing post-revolutionary Egyptian ‘Arab Spring/Islamist Winter.’ My participants did not rely on state-discipline and carceral punishment mechanisms nor did they seek to replicate the reproduction of patriarchal violence towards abusers. Rather, through knowledge production (al-intag al-marify) they sought a more compassionate-transformative justice approach in combatting harassment that centered on illuminating harassment as a micro-fascistic cis-heteropatriarchal by-product emergent from macro-fascistic statist and capitalist structural hierarchies and inequities that cyclically reify each other at the vertical and horizontal level. Even prior to a covet19-viral laden world, they recognized that there is nowhere left to hide (if there ever was one for innumerable disenfranchised racialized/queered/feminized/classed/disabled/debilitated lives marked and targeted by a necro-politics of death. They gesture towards a non-ideological revolutionary driven ethics and politics that demands that we must all ask how we will collectively decide how live or die. They reject playing to a statist-politics of recognition, reform and rights, or recourse to martial and emergency laws that are contingent on and reify capitalist-state paradigms that (further) strips and extinguishes our communitarian and individual agency as a species. Instead, they argue for a politics of responsibility that focuses on interconnecting the burning ashes, timbres, and fires of our intersecting local, regional, and transnational struggles through mutual aid and social solidarity towards each other and nonhuman life.

Chaos Engineering (Principles of Chaos Engineering) As the Pathway to Excellence and Relevance in Engineering Education in Africa

A study on engineering in sub-Saharan Africa revealed that engineering is pivotal for economic and social development of any country. This is profound as it underscores the potentials embedded in engineering education for excellence and relevance in Africa. This has not been the case in Africa, as the region has not developed evenly with other countries from the Global South. Hence, the impetus for chaos engineering as a panacea to excellence and relevance in engineering education in Africa. Chaos engineering has been defined by various authors and one of the profound definitions is that chaos engineering is the discipline of experimenting on a distributed system with the intent to build confidence in the system`s capability to withstand turbulent conditions during production. This study therefore looked at chaos engineering, its history and applicability and conceptualize it as a pathway for excellence and relevance in engineering education in Africa. Findings from the that engineering is pivotal for economic and social development of any country but it has not resulted to such in Africa which necessitates chaos principles. It was found out that experimentation is a basic principle of chaos engineering while the advanced principles are hypothesizing about steady state, vary real-world events, run experiments in production, automate experiments to run continuously, minimize blast radius. These all were conceptualized as the pathway to excellence and relevance in engineering education in Africa. The study recommended that there is a need to intensify effort on researching more into chaos engineering in Africa.

BLAST RADIUS: No. 4 in a Series of Data Humanization Performances

At around 7:30pm on April 13, 2017 the US government dropped the Massive Ordnance Air Blast (MOAB) bomb near the Moman Dara Village in the Asadkhel area in the Achin district of Nagarhar province in eastern Afghanistan. Nicknamed the "Mother of All Bombs" the weapon is the largest non-nuclear weapon in the US arsenal, with a blast radius, meaning the area in which serious effects on people and structures can be felt, of a mile. While the MOAB was the largest weapon released, it was but one of 4,361 air weapons that targeted Afghanistan during 2017, according to US Air Forces Central Command declassified airpower summaries. At 7:30am on April 13, 2018, the anniversary of this event, I walked a path equivalent to the blast radius of MOAB on land in Arizona. This walk memorialized the civilians killed, the villages terrorized, the populations forced to migrate, and the lands scarred as a result of the endless wars being carried out in the name of protecting US citizens.

Perencanaan Rute Evakuasi pada Kasus Kebocoran Pipa Gas Alam dengan Simulasi Berbasis Computational Fluid Dynamic

Melting of metals generally used the energy source of natural gas which is flowed through a pipeline at high pressure. Production activities in companies that use these gases have high potential hazards because they can cause fires or explosions if not managed properly. This study aims to analyzed natural gas dispersion in the event of gas pipeline leak, determine assembly point and evacuation route map plan for workers in the event of emergency condition. Natural gas dispersion was simulated using Computational Fluid Dynamic Ansys Fluent. Results of simulation showed distribution concentration of natural gas indoors at leakage almost uniform with concentration between 5%-13,17%. At that concentration the mixture of air and natural gas has the potential to explode because it is in the range of natural gas flammability. The maximum natural gas concentration of 13.17% at a height of 12 m above the leak hole. Generated two points Assembly point based on the calculation of blast radius with total area of 58,500 cm2 and can accommodate as many as 65 workers. Keywords :CFD Simulation, Natural Gas Dispersion, Assembly point, Evacuation Rute

On the thermomechanics and footprint of fragmenting blasts

In this paper, a mathematical model is developed to simulate the progressive time-evolution of an object that fragments, which may contain biohazardous materials or materials that may thermally degrade into a toxic state. Estimates are made for the blast radius that one can expect for a given amount of detonation energy and the resulting atmospheric heating of fragments. The atmospheric heating of the fragments is important, since if the heating is sufficiently high, the biohazardous material can be neutralized. If the material is not heated sufficiently, then the location in which it lands can be considered as “contaminated”. This analysis is useful is determining safe areas after such a blast. Ascertaining the temperature of the fragments is extremely difficult to measure in experiments, thus motivating the development of the model. The model balances the released energy from the initial blast pulse with the subsequent kinetic energy and then numerically computes the trajectory of the fragments under the influence of the drag from the surrounding air and gravity. Preliminary field experiments with explosives are described and the results are compared to the output from the model. The subsequent drag heating of the material is then computed in order to ascertain the temperature of the blast fragments.

On firework blasts and qualitative parameter dependency.

In this paper, a mathematical model is developed to qualitatively simulate the progressive time-evolution of a blast from a simple firework. Estimates are made for the blast radius that one can expect for a given amount of detonation energy and pyrotechnic display material. The model balances the released energy from the initial blast pulse with the subsequent kinetic energy and then computes the trajectory of the material under the influence of the drag from the surrounding air, gravity and possible buoyancy. Under certain simplifying assumptions, the model can be solved for analytically. The solution serves as a guide to identifying key parameters that control the evolving blast envelope. Three-dimensional examples are given.

Exploding Targets in Recreational Use

Exploding targets are marketed for their ability to indicate long-range marksmanship by detonating upon high velocity impact. The Internet has popularized recreational use of these targets outside of the scope of their intended design. We present a case of a 47-year-old man who was a bystander during recreational use of exploding targets. A .300 Winchester Magnum rifle was used to detonate an exploding target, on top of which was placed a fire extinguisher inside an aluminum pipe. The decedent was struck in the abdomen by a fragment of aluminum and collapsed. Despite emergency efforts at the scene, he was pronounced dead. Scene investigation revealed aluminum fragments throughout the blast radius. External examination and postmortem radiograph showed an entry wound of the left mid-abdomen without evidence of retained shrapnel. The autopsy findings included a hemoperitoneum due to transection of the right common iliac artery and inferior vena cava. A 10.6 g fragment of aluminum was recovered from within the abdomen. This case illustrates a dangerous misuse of exploding targets that has been popularized in the media. It also exemplifies a potential pitfall of a negative radiograph, despite the presence of metal shrapnel, because of the radiolucency of aluminum.

Optical observations of meteors generating infrasound: Weak shock theory and validation

AbstractWe have recorded a data set of 24 cm sized meteoroids detected simultaneously by video and infrasound to critically examine the ReVelle (1974) weak shock meteor infrasound model. We find that the effect of gravity wave perturbations to the wind field and updated absorption coefficients in the linear regime on the initial value of the blast radius (R0), which is the strongly nonlinear zone of shock propagation near the body and corresponds to energy deposition per path length, is relatively small (<10%). Using optical photometry for ground truth for energy deposition, we find that the ReVelle model accurately predicts blast radii from infrasound periods (τ) but systematically underpredicts R0 using pressure amplitude. If the weak shock to linear propagation distortion distance is adjusted as part of the modeling process, we are able to self‐consistently fit a single blast radius value for amplitude and period. In this case, the distortion distance is always much less (usually just a few percent) than the value of 10% assumed in the ReVelle model. Our study shows that fragmentation is an important process even for centimeter‐sized meteoroids, implying that R0, while a good measure of energy deposition by the meteoroid, is not a reliable means of obtaining the meteoroid mass. We derived an empirical period‐blast radius relation of the form R0 = 15.4τ − 0.5 (τ ≤ 0.7 s) and R0 = 29.1τ − 11.6 (τ > 0.7 s) appropriate to centimeter‐sized meteoroids. Our observations suggest that meteors having blast radii as small as 1 m are detectable infrasonically at the ground, an order of magnitude smaller than previously considered.