The sound of a deflagration, Elon's "fast fire," is different from that of a detonation wave.
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A deflagration wave is subsonic, or slower than the speed of sound, whereas a detonation wave is supersonic, faster than the speed of sound.
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The combustion tube is meant to test flame acceleration and deflagration to detonation transition, which, sure, but it's also fantastic to blow things up with.
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According to the Chinese Foreign Ministry, the crew on board the Sanchi died within an hour of the accident "because of the large-scale deflagration and the toxic gas."
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Deflagration to detonation transition (DDT) refers to a phenomenon in ignitable mixtures of a flammable gas and air (or oxygen) when a sudden transition takes place from a deflagration type of combustion to a detonation type of explosion.
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Comparing explosions of initially unmixed fuels is difficult (being part detonation and part deflagration).
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Subsonic explosions are created by low explosives through a slower burning process known as deflagration.
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Damage to buildings, equipment and people can result from a large-scale, short-duration deflagration. The potential damage is primarily a function of the total amount of fuel burned in the event (total energy available), the maximum flame velocity that is achieved, and the manner in which the expansion of the combustion gases is contained. In free-air deflagrations, there is a continuous variation in deflagration effects relative to the maximum flame velocity. When flame velocities are low, the effect of a deflagration is to release heat.
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The phenomenon is exploited in pulse detonation engines, because a detonation produces a more efficient combustion of the reactants than a deflagration does, i.e. giving a higher yields. Such engines typically employ a Shchelkin spiral in the combustion chamber to facilitate the deflagration to detonation transition. The mechanism has also found military use in thermobaric weapons.
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Explosion or deflagration pressures are the result of the ignition of explosive gases, mists, dust/air suspensions, in unconfined and confined spaces.
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An analogous deflagration to detonation transition (DDT) has also been proposed for thermonuclear reactions responsible for supernovae initiation. This process has been called a "carbon detonation".
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The heat released by the deflagration causes the combustion gases and excess air to expand thermally. The net result is that the volume of the vessel or structure must expand to accommodate the hot combustion gases, or the vessel must be strong enough to withstand the additional internal pressure, or it fails, allowing the gases to escape. The risks of deflagration inside waste storage drums is a growing concern in storage facilities.
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The Shchelkin spiral is a device that assists the transition from deflagration (subsonic combustion) to detonation in a pulse detonation engine. The spiral is named after Kirill Ivanovich Shchelkin, a Russian physicist who described it in his 1965 book Gas Dynamics of Combustion.. In pulse detonation engines, direct detonation of the combustible mixture can be relatively straightforward, but require more energy than when detonation is preceded by deflagration. The deflagration to detonation transition (DDT) must however occur within the length of the detonation tube, which can be solved by providing the Shchelkin spiral. The Shchelkin spiral acts as an obstacle by creating a partial blockage of the detonation tube, effectively shortening the distance along the detonation tube in which the transition occurs..
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As such, the accident is widely quoted as one of the first, if not the first, confirmed accidental occurrences of an unconfined vapor cloud deflagration that turns into a detonation - a so-called deflagration to detonation transition. The accident represents a "worst- possible" sort of case history for assessment of the hazards of fuel transportation. The accident took place in Port Hudson, Franklin County, Missouri, on December 9, 1970. The pipeline was owned by Phillips Pipeline Company.
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Combustion can vary in degree of violence. A deflagration is a propagation of a combustion zone at a velocity less than the speed of sound in the unreacted medium. A detonation is a propagation of a combustion zone at a velocity greater than the speed of sound in the unreacted medium. An explosion is the bursting or rupture of an enclosure or container due to the development of internal pressure from a deflagration or detonation as defined in NFPA 69.
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Low explosives are compounds where the rate of decomposition proceeds through the material at less than the speed of sound (). The decomposition is propagated by a flame front (deflagration) which travels much more slowly through the explosive material than a shock wave of a high explosive. Under normal conditions, low explosives undergo deflagration at rates that vary from a few centimetres per second to approximately . It is possible for them to deflagrate very quickly, producing an effect similar to a detonation.
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300px The M84 features a magnesium-based pyrotechnic charge inside a thin aluminum case, contained within a perforated cast steel body. Unlike the high explosives (HE) used in traditional ordnance, the pyrotechnic charge produces a subsonic deflagration, not a supersonic detonation, minimizing the blast effects. On initiation the auditory and visual elements of the deflagration being permitted to escape via the perforations in the cast outer body. This design minimizes the risk of collateral damage due to flame, blast and unconsumed fragments of the inner case.
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A deflagration is characterized by a subsonic flame propagation velocity, typically far below , and relatively modest overpressures, typically below . The main mechanism of combustion propagation is of a flame front that moves forward through the gas mixture - in technical terms the reaction zone (chemical combustion) progresses through the medium by processes of diffusion of heat and mass. In its most benign form, a deflagration may simply be a flash fire. In contrast, a detonation is characterized by supersonic flame propagation velocities, perhaps up to , and substantial overpressures, up to .
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Avoidance will make it impossible for an explosion or deflagration to occur, for instance by means of suppressing the heat and the pressure needed for an explosion using aluminum mesh structure such as eXess, by means of consistent displacement of the O2 necessary for an explosion or deflagration to take place, by means of padding gas (f. i. CO2 or N2), or, by means of keeping the concentration of flammable content of an atmosphere consistently below or above the explosive limit, or, by means of consistent elimination of ignition sources.
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A flame arrester during testing A flame arrester made for a 91 cm (36 inch) pipe weighing 10 tons A flame arrester (also spelled arrestor), deflagration arrester, or flame trap is a device that stops fuel combustion by extinguishing the flame.
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While it is possible to start a detonation directly with a large spark, the amount of energy input is very large and is not practical for an engine. The typical solution is to use a deflagration-to-detonation transition (DDT)—that is, start a high-energy deflagration, and have it accelerate down a tube to the point where it becomes fast enough to become a detonation. Alternatively the detonation can be sent around a circle and valves ensure that only the highest peak power can leak into exhaust. Also the pulse compression detonation system can be applied to solve the initiation problem.
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BNCP, (cis- bis-(5-nitrotetrazolato)tetraminecobalt(III) perchlorate) is another common initiator material. It is relatively insensitive. It undergoes deflagration to detonation transition in a relatively short distance, allowing its use in detonators. Its burning byproducts are of relatively little harm to environment.
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Smokeless powders are classified as, typically, division 1.3 explosives under the UN Recommendations on the transportation of Dangerous goods – Model Regulations, regional regulations (such as ADR) and national regulations. However, they are used as solid propellants; in normal use, they undergo deflagration rather than detonation.
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It has a very slow decomposition rate, and therefore a very low brisance. It is not, in the strictest sense of the term, an explosive, but a "deflagrant", as it does not detonate but decomposes by deflagration due to its subsonic mechanism of flame-front propagation.
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The chemical decomposition of an explosive may take years, days, hours, or a fraction of a second. The slower processes of decomposition take place in storage and are of interest only from a stability standpoint. Of more interest are the other two rapid forms besides decomposition: deflagration and detonation.
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In addition, mixtures of excessive quantities of air and gas should be avoided as this could lead to the deflagration (explosion) of the gas in question if a combustion source is present. Long- term storage of wood-gas, except through the use of a gasholder-type water- displacement apparatus, should not be attempted, due to the volatile elements present in the gas, which, if allowed to excessively precipitate, will condense in the storage vessel. Under no circumstances should wood-gas ever be compressed to more than above ambient, as this may induce condensation of volatiles, as well as lead to the likelihood of severe injury or death due to carbon monoxide or deflagration if the vessel leaks or fails.
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In July he won the British tournament Albion 2, and won Respawn 5 in Germany a month later. He took 3rd in Syndicate 2017 in September. In January 2018, Glutonny won the Danish tournament Valhalla, using Wario, Cloud Strife, and Donkey Kong. He won Deflagration, held in Strasbourg, the following month.
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A blast injury is a complex type of physical trauma resulting from direct or indirect exposure to an explosion. Blast injuries occur with the detonation of high-order explosives as well as the deflagration of low order explosives. These injuries are compounded when the explosion occurs in a confined space.
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In some cases explosives can be made to fall into either class by the conditions under which they are initiated. In sufficiently large quantities, almost all low explosives can undergo a Deflagration to Detonation Transition (DDT). For convenience, low and high explosives may be differentiated by the shipping and storage classes.
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The heat liberated raises the temperature to about . This is entirely different from deflagration, which depends solely upon available fuel regardless of pressure or shock. The decomposition results in much higher ratio of energy to gas moles released compared to other explosives, making it one of the hottest detonating high explosives.
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Many of the injured were very close to the gas leak or sleeping in their homes. The lack of information on how to act in situations of this kind caused people not to worry too much about the fact until a few seconds before the deflagration, which contributed to the large number of people injured.
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When it reached a set of heaters 170 metres away, it ignited. This caused a deflagration (a burning vapour cloud). The flame front burnt its way through the vapour cloud, without causing an explosion. When the flamefront reached the rupture in the heat exchanger, a fierce jet fire developed that lasted for two days.
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The remaining unburned propellant shattered allowing more surface area of the rocket motor to burn, in turn increasing the pressure and rate of combustion to a speed that was no longer considered burning but was now a deflagration and destroyed the tower, and the pilot was disqualified because the judges refused to believe it was unarmed.
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G2ZT is a bistetrazole. It is an explosive approximately as powerful as RDX, but it releases less toxic reaction products when detonated: ammonia and hydrogen cyanide. When combined with ADN or AN oxidizers, the amount of HCN produced by a deflagration may be reduced. The compound is thus considered by its advocates to be an environmentally friendlier explosive than traditional nitroamine-based explosives.
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The sensitivity of NHN straddles the line between highly sensitive primaries and a sensitive secondary. Due to this fact, NHN can be considered a true Non-primary explosive detonator. (NPED) An added benefit of NHN is that it will make the DDT (Deflagration to Detonation) transition in a cardboard shell, thus eliminating any chance of shrapnel danger posed by using metal shells.
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In this article, explosion means "the sudden conversion of potential energy (chemical or mechanical) into kinetic energy", p. 408 as defined by the US National Fire Protection Association, or the common dictionary meaning, "a violent and destructive shattering or blowing apart of something". No distinction is made as to whether it is a deflagration with subsonic propagation or a detonation with supersonic propagation.
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HBT is a bistetrazole. It is an explosive approximately as powerful as HMX or CL-20, but it releases less toxic reaction products when detonated: ammonia and hydrogen cyanide. When combined with ADN or AN oxidizers, the amount of HCN produced by a deflagration may be reduced. The compound is thus considered by its advocates to be a more environmentally friendly explosive than traditional nitroamine-based explosives.
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Wood in a fireplace. Deflagration (Lat: de + flagrare, "to burn down") is subsonic combustion propagating through heat transfer; hot burning material heats the next layer of cold material and ignites it. Most "fires" found in daily life, from flames to explosions such as that of black powder, are deflagrations. This differs from detonation, which propagates supersonically through shock waves, decomposing a substance extremely quickly.
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RDX has a high nitrogen content and a high O:C ratio, both of which indicate its explosive potential for formation of N2 and CO2. RDX undergoes a deflagration to detonation transition (DDT) in confinement and certain circumstances. The velocity of detonation of RDX at a density of 1.76 g/cm3 is 8750 m/s. It starts to decompose at approximately 170 °C and melts at 204 °C.
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Lead azide has immediate deflagration to detonation transition (DDT), meaning that even small amounts undergo full detonation (after being hit by flame or static electricity). Lead azide reacts with copper, zinc, cadmium, or alloys containing these metals to form other azides. For example, copper azide is even more explosive and too sensitive to be used commercially. Lead azide was a component of the six .
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In October 2020, a Tallboy bomb was found in the Piast Canal in northwest Poland near the town of Świnoujście and scheduled for defusing. The bomb had been dropped in the April 1945 attack on the Lützow, a German cruiser. The Tallboy wound up detonating during a deflagration operation, but there were no reported injuries to divers nor any damage to the port infrastructure from the underwater explosion.
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Some authors use the term flash fire to describe these low-speed deflagrations. At flame velocities near the speed of sound, the energy released is in the form of pressure and the results resemble a detonation. Between these extremes, both heat and pressure are generated. When a low-speed deflagration occurs within a closed vessel or structure, pressure effects can produce damage due to expansion of gases as a secondary effect.
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However some environmental groups say this phase-out of fossil fuel vehicles must be brought forward to limit climate change. Production of gasoline fueled cars peaked in 2017. Other hydrocarbon fossil fuels also burnt by deflagration (rather than detonation) in ICE cars include diesel, Autogas and CNG. Removal of fossil fuel subsidies, concerns about oil dependence, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for cars.
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A fuse is made to project out, then lit, and the resulting deflagration sends the projectile anvil several feet into the air. Anvils were traditionally fired on St. Clement's Day, honoring Pope Clement I, the patron saint of blacksmiths and metalworkers. Although its practice has lessened in recent years, enthusiasts still participate in anvil launching events and competitions. On September 5, 2011, The Science Channel premiered Flying Anvils, a reality television series about anvil firing.
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In 2005, Congress held new hearings on lingering security issues at Los Alamos National Weapons Laboratory in New Mexico. But documented problems continued to be ignored. In November 2008 a drum containing nuclear waste was ruptured due to a 'deflagration' according to an inspector general report of the Dept. of Energy, which due to lab mistakes, also occurred in 2014 at the Carlsbad plant with significant disruptions and costs across the industry.
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The effect is most commonly associated with a nuclear explosion, but any sufficiently energetic detonation or deflagration will produce the same effect. They can be caused by powerful conventional weapons, like thermobaric weapons, including the ATBIP and GBU-43/B Massive Ordnance Air Blast. Some volcanic eruptions and impact events can produce natural mushroom clouds. Mushroom clouds result from the sudden formation of a large volume of lower-density gases at any altitude, causing a Rayleigh–Taylor instability.
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Sulfur should be avoided in pyrotechnic compositions containing potassium chlorate, as these mixtures are prone to spontaneous deflagration. Most sulfur contains trace quantities of sulfur-containing acids, and these can cause spontaneous ignition - "Flowers of sulfur" or "sublimed sulfur", despite the overall high purity, contains significant amounts of sulfur acids. Also, mixtures of potassium chlorate with any compound with ignition promoting properties (ex. antimony(III) sulfide) are very dangerous to prepare, as they are extremely shock sensitive.
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Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance. These produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not so quickly as to routinely destroy the barrel of the gun. Cordite was used initially in the .
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An armoured cruiser, , was a fourth ship to suffer an explosive deflagration at Jutland with at least 893 men killed. The rear magazine was seen to detonate followed by more explosions as the cordite flash travelled along an ammunition passage beneath her broadside guns. Eyewitness reports suggest that may also have suffered an explosion as she was lost during the night action with all hands — 857 men. British reports say she was seen to blow up.
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The Zalău explosion occurred on September 14, 2007 in a block of flats in Zalău, Romania as the result of a gas leak. Two people died and eight were injured in the explosion.România Liberă, Explozie devastatoare la Zalau: 2 morti, 15 raniti The structure was severely affected and the block of flats E24 was demolished in October 2007.Blocul din Zalău avariat de explozie este demolat astăzi A total of 19 families were affected by the deflagration.
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The tests delivered good overall results except for one of the outer engines experiencing thrust fluctuations. Elon Musk reported that this may have been due to debris ingestion. The booster was then retired to the SpaceX facility in Hawthorne, California. First stage of Falcon 9 Flight 21 descending over the floating landing platform, January 17, 2016, immediately prior to a soft touchdown followed by deflagration of the rocket after a landing leg failed to latch, causing the rocket to tip over.
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Green mix is an early step in the manufacturing of black powder for explosives. It is a rough mixture of potassium nitrate, charcoal and sulfur in the correct proportions (75:15:10) for black powder, but is not milled, pressed or corned. It burns much more slowly than black powder, when it chooses to burn at all, can still explode if ignited in a confined place; the deflagration is usually characterized by short, uneven sizzling followed by relatively long periods of smoulder.
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Located inside the turret bustle, the autoloader is designated CHA (, "automatic loading") and was designed by Creusot-Loire Industrie. The autoloader itself weighs 500 kg (empty) and has a total volume of 1.68 m3 (1.40 x 2.40 x 0.50 m). In case of ammunition cooking off, the deflagration is vented by two blow-out panels. The autoloader allows the reloading of the gun while firing on the move, providing it a sufficient rate of fire to deal with six targets in one minute.
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His SoundBlast invention eliminates the deflagration process in the creation of a detonation wave in a short tube, enabling a timing accuracy of sub 20µs. This timing accuracy allows for the assembly of very useful arrays of coherent detonation tubes. His detonation wave technology has applications in propulsion, weapons, and as a high energy impulse seismic source. In 2006, Fullerton and co-founder Mark Roberts founded Cedar Ridge Research in order to develop new technologies in a wide variety of fields.
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A main sequence star supported by thermal pressure can expand and cool which automatically regulates the increase in thermal energy. However, degeneracy pressure is independent of temperature; white dwarfs are unable to regulate temperature in the manner of normal stars, so they are vulnerable to runaway fusion reactions. The flare accelerates dramatically, in part due to the Rayleigh–Taylor instability and interactions with turbulence. It is still a matter of considerable debate whether this flare transforms into a supersonic detonation from a subsonic deflagration.
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Pressure piling describes phenomena related to combustion of gases in a tube or long vessel. As the flame front propagates along the tube, the unburned gases ahead of the front are compressed, and hence heated. The amount of compression varies depending on the geometry and can range from twice to eight times the initial pressure. Where multiple vessels are connected by piping, ignition of gases in one vessel and pressure piling may result in a deflagration to detonation transition and very large explosion pressure.
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The Minié ball is a conical bullet with three exterior grease-filled grooves and a conical hollow in its base. The bullet was designed by Minié with a small iron plug and a lead skirting. Its intended purpose was to expand under the pressure of the powder deflagration, pressing the skirt out to grip the rifling, and secondarily to obturate the barrel and increase muzzle velocity. The precursor to the Minié ball was created in the 1830s by the French Army captains Montgomery and Henri-Gustave Delvigne.
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The other failure mode is a deflagration to detonation transition; the supersonic pressure wave formed in the combustion chamber may destroy the engine. Combustion instability was also a problem during Atlas development. The Rocketdyne engines used in the Atlas family were found to suffer from this effect in several static firing tests, and three missile launches exploded on the pad due to rough combustion in the booster engines. In most cases, it occurred while attempting to start the engines with a "dry start" method whereby the igniter mechanism would be activated prior to propellant injection.
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Because of its popularity that video retroactively had the Smarter Every Day label added to it. Sandlin formally launched the Smarter Every Day series on April 24, 2011 with a video titled "Detonation vs Deflagration - Smarter Every Day 1," which became the title format for subsequent videos and the sole focus of his YouTube channel. Episodes of Smarter Every Day feature Sandlin as the host and narrator, and revolve around scientific exploration and discovery. Sandlin's primary interest and educational background is in flight and space, which appear frequently in his videos.
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A dynamite gun is any of a class of artillery pieces that use compressed air to propel an explosive projectile (such as one containing dynamite). Dynamite guns were in use for a brief period from the 1880s to the beginning of the twentieth century. Because of the instability of early high explosives, it was impractical to fire an explosive-filled shell from a conventional gun. The violent deflagration of the propellant charge and the sudden acceleration of the shell would set off the explosive in the barrel of the weapon.
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The fleet was to ultimately reach Bona, Algeria, where it would surrender to Allied forces. A few hours later, off Asinara island, the squadron was attacked by German Dornier Do 217 bombers carrying Fritz X radio- controlled bombs; two of them hit Roma, which sank after the violent deflagration of the forward ammunition magazines. Captain Del Cima and Admiral Bergamini went down with the ship, along with 1,391 officers and men. Del Cima was posthumously awarded the Silver Medal of Military Valor, but the decoration was never handed over to his relatives.
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When used in explosive devices, the main cause of damage from a detonation is the supersonic blast front (a powerful shock wave) in the surrounding area. This is a significant distinction from deflagrations where the exothermic wave is subsonic and maximum pressures are at most one eighth as great. Therefore, detonation is a feature for destructive purpose while deflagration is favored for the acceleration of firearms' projectiles. However, detonation waves may also be used for less destructive purposes, including deposition of coatings to a surface or cleaning of equipment (e.g.
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Unintentional detonation when deflagration is desired is a problem in some devices. In Otto cycle, or gasoline engines it is called engine knocking or pinging or pinking, and it causes a loss of power, excessive heating, and harsh mechanical shock that can result in eventual engine failure.See article on engine knocking In firearms, it may cause catastrophic and potentially lethal failure. Pulse detonation engines are a form of pulsed jet engine that have been experimented with on several occasions as this offers the potential for good fuel efficiency.
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All regular jet engines and most rocket engines operate on the deflagration of fuel, that is, the rapid but subsonic combustion of fuel. The pulse detonation engine is a concept currently in active development to create a jet engine that operates on the supersonic detonation of fuel. Because the combustion takes place so rapidly, the charge (fuel/air mix) does not have time to expand during this process, so it takes place under almost constant volume. Constant volume combustion is more efficient than open-cycle designs like gas turbines, which leads to greater fuel efficiency.
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British technical experts created the first "flash bang" or "stun" grenade for the Special Air Service's Counter terrorist wing.Bonneville, Leigh, The SAS 1983-2014 (Elite), Osprey Publishing, 2016, , p.9 Unlike a fragmentation grenade, stun grenades are constructed with a casing made to remain intact during deflagration and avoiding fragmentation injuries, while having large circular cutouts to allow the light and sound of the explosion through. The filler consists of a pyrotechnic metal-oxidant mix of magnesium or aluminium and an oxidizer such as potassium perchlorate or potassium nitrate.
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The commentary by BATFE staff in response to objections to adding new enforcement against hobby rocket motors is quite instructive. In 2009, the court ruled in favor of the hobby organizations and ordered the BATF to remove APCP and other slow burning materials from its list of regulated explosives. That judgement established 1 meter per second burning rate ("ATFE’s own burn rate threshold for deflagration is 1000 millimeters (or one meter) per second." Tripoli Rocketry Ass’n, 437 F.3d at 81-82) as the threshold for a material on the BATFE list of explosive materials.
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Flame arresters should be used only in the gas group and conditions they have been designed and tested for. Since the depth on an arrester is specified for certain conditions, changes in the temperature, pressure, or composition of the gases entering the arrester can cause the flame spatial velocity to increase, making the design of the arrester insufficient to stop the flame front ("propagation"). The deflagration may continue downstream of the arrester. Flame arresters should be periodically inspected to make sure they are free of dirt, insects using it as a nest, or corrosion.
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This can happen under higher pressure or temperature, which usually occurs when ignited in a confined space. A low explosive is usually a mixture of a combustible substance and an oxidant that decomposes rapidly (deflagration); however, they burn more slowly than a high explosive, which has an extremely fast burn rate. Low explosives are normally employed as propellants. Included in this group are petroleum products such as propane and gasoline, gunpowder (including smokeless powder), and light pyrotechnics, such as flares and fireworks, but can replace high explosives in certain applications, see gas pressure blasting.
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It has been thought that the most likely cause of her loss was a deflagration or low-order explosion in 'X' magazine that blew out her bottom and severed the steering control shafts, followed by the explosion of her forward magazines from the second volley.Roberts, p. 116. More recent archaeological evidence shows that the ship was actually blown in half within the opening minutes of the engagement with Von der Tann which fired only fifty-two shells at Indefatigable before the fore part of the ship also exploded.McCartney (2017b), pp.
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On 31 May 1916, three British battlecruisers were destroyed by cordite deflagrations initiated by armour-piercing shells fired by the German High Seas Fleet. At 16:02 was cut in two by deflagration of the forward magazine and sank immediately with all but two of her crew of 1,019. German eyewitness reports and the testimony of modern divers suggest all her magazines exploded. The wreck is now a debris field. At 16:25 was cut in two by detonation of the forward magazine and sank with all but 21 of her crew of 1,283.
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The booster was fitted with a variety of technologies to facilitate the flight test, including grid fins and landing legs to facilitate the post-mission test. If successful, this would have been the first time in history that a rocket booster was returned to a vertical landing. On 15 April, SpaceX released a video of the terminal phase of the descent, the landing, the tip over, and a small deflagration as the stage broke up on the deck of the ASDS.CRS-6 First Stage Landing, SpaceX, 15 April 2015.
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In practical use, such conditions are impossible to attain, and blasts produce moderate amounts of toxic gases such as carbon monoxide and nitrogen oxides (NOx). The fuel component of ANFO is typically diesel, but kerosene, coal dust, racing fuel, or even molasses have been used instead. Finely powdered aluminium in the mixture will sensitise it to detonate more readily. ANFO is classified as a blasting agent, meaning that it decomposes through detonation rather than deflagration at a velocity higher than the speed of sound in the material but cannot be detonated with a No. 8 blasting cap without a sensitizer.
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Most guns use compressed gas confined by the barrel to propel the bullet up to high speed, though devices operating in other ways are sometimes called guns. In firearms the high- pressure gas is generated by combustion, usually of gunpowder. This principle is similar to that of internal combustion engines, except that the bullet leaves the barrel, while the piston transfers its motion to other parts and returns down the cylinder. As in an internal combustion engine, the combustion propagates by deflagration rather than by detonation, and the optimal gunpowder, like the optimal motor fuel, is resistant to detonation.
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During this phase the electrical resistance of the bridgewire assembly rises. Then an electric arc forms in the metal vapor, leading to drop of electrical resistance and sharp growth of the current, quick further heating of the ionized metal vapor, and formation of a shock wave. To achieve the melting and subsequent vaporizing of the wire in time sufficiently short to create a shock wave, a current rise rate of at least 100 amperes per microsecond is required. If the current rise rate is lower, the bridge may burn, perhaps causing deflagration of the PETN pellet, but it will not cause detonation.
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Because of this, the LPG which contained the truck began to escape from the tank in a matter of minutes, expanding by about 250 meters. The truck driver got off and tried to repair and close the valve without success, so he started yelling at people to get away from the place. After the expansion of the gas by a block, there was a deflagration caused by a small spark that was advancing until it reached the tank truck. As a result, one person died instantly and several were injured, in addition to causing several fires throughout that block.
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Technically, only devices that use spin-stabilized projectiles fired from a rifled barrel are recoilless rifles, while smoothbore variants (which can be fin-stabilized or unstabilized) are recoilless guns. This distinction is often lost, and both are often called recoilless rifles. Though similar in appearance to a tube-based rocket launcher (since these also operate on a recoilless launch principle), the key difference is that recoilless weapons fire shells utilizing a conventional smokeless propellant. While there are rocket-assisted rounds for recoilless weapons, they are still ejected from the barrel by the deflagration of a conventional propelling charge.
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Liquid seal flame arrestors are liquid barriers following the principle of a siphon where the liquid stops the entering deflagration and/or detonation and extinguishes the flame, they work by bubbling the gas through a non-flammable and ideally non-gas-absorbing liquid, which is typically water. They stop the flame by preventing it from reaching the submerged intake. These devices are normally very effective at stopping flashbacks from reaching the protected side of the system. They have the disadvantages of only working in one orientation and tend to be much larger than dry type arrestors.
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Tunneling of magnetization Chudnovsky explained magnetic avalanches experimentally observed in molecular magnets as deflagration."Magnetic flames" Chudnovsky received his undergraduate, graduate, and postdoctoral education at Kharkiv University in Ukraine, in the school of theoretical physics founded by Lev Landau and his students. The denial by USSR of exit visa to Chudnovsky in 1979 led to his unemployment for eight years during which he continued independent research in theoretical physics and participated in the unofficial Refusenik Science Seminar in Moscow.Making Waves: Stories from My Life by Yakov Alpert He was frequently harassed and interrogated by the KGB.
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Mixtures of dispersed combustible materials (such as gaseous or vaporised fuels, and some dusts) and oxygen in the air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to as flammability limits or explosive limits. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both to producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust.
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The method of powder application at the concert created "an extremely dense dust cloud over the stage and its immediate vicinity", people near the stage were standing "almost ankle-deep" in colored corn starch powder, and the powder was repeatedly suspended into the air using air blowers as well as compressed gas canisters. At about 20:30, a large deflagration occurred when a cloud of colored powder ignited after being discharged from the stage onto a crowd of 1,000 people during a concert. Some of the crowd breathed in the powder, causing respiratory problems. As recorded in an amateur video by an audience member, a massive fireball suddenly engulfed the stage.
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The strong heating leads to wood gas deflagration which, if the covering of the pile is too strong, to an explosion. At the top as well as at the foot of the pile, individual holes are made in the surface, by means of which the fire in the pile is regulated. Under this blanket, incineration is conducted with carefully regulated air access in such a way that, if possible, no more wood burns than is absolutely necessary to heat the entire wood mass to the charring temperature. The wood must char, not burn, inside the pile; air being let in through the small holes so that no fire can start.
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In engineering applications, deflagrations are easier to control than detonations. Consequently, they are better suited when the goal is to move an object (a bullet in a firearm, or a piston in an internal combustion engine) with the force of the expanding gas. Typical examples of deflagrations are the combustion of a gas-air mixture in a gas stove or a fuel-air mixture in an internal combustion engine, and the rapid burning of gunpowder in a firearm or of pyrotechnic mixtures in fireworks. Deflagration systems and products can also be used in mining, demolition and stone quarrying via gas pressure blasting as a beneficial alternative to high explosives.
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Falcon 9 Flight 21 launched the Jason-3 satellite on January 17, 2016, and attempted to land on the floating platform Just Read the Instructions, located for the first time about out in the Pacific Ocean. Approximately 9 minutes into the flight, the live video feed from the drone ship went down due to the losing its lock on the uplink satellite. The vehicle landed smoothly onto the vessel but one of the four landing legs failed to lock properly, reportedly due to ice from the heavy pre-launch fog preventing a lockout collet from latching. Consequently the booster fell over shortly after touchdown and was destroyed in a deflagration upon impact with the pad.
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During normal plant operations and in normal operating temperatures, the hydrogen generation is not significant. When the nuclear fuel overheats, zirconium in Zircaloy cladding used in fuel rods oxidizes in reaction with steam: :Zr + 2H2O → ZrO2 \+ 2H2 When mixed with air, hydrogen is flammable, and hydrogen detonation or deflagration may damage the reactor containment. In reactor designs with small containment volumes, such as in Mark I or II containments, the preferred method for managing hydrogen is pre-inerting with inert gas—generally nitrogen—to reduce the oxygen concentration in air below that needed for hydrogen combustion, and the use of thermal recombiners. Pre-inerting is considered impractical with larger containment volumes where thermal recombiners and deliberate ignition are used.
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By the 20th century, the weapon had become so common that the modern noun "rifle" is now often used for any long- shaped handheld ranged weapon designed for well-aimed discharge activated by a trigger (e.g., personnel halting and stimulation response rifle, which is actually a laser dazzler). Like all typical firearms, a rifle's projectile (bullet) is propelled by the contained deflagration of a combustible propellant compound (originally black powder, later cordite, and now nitrocellulose), although other propulsive means such as compressed air are used in air rifles, which are popular for vermin control, small game hunting, competitive target shooting and casual sport shooting ("plinking"). The distinct feature that separates a rifle from the earlier smoothbore long guns (e.g.
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However no satisfactory mechanism was advanced for the sudden ingress of such an amount of water, amounting to a couple of tons. Neither were victims of the explosion scalded, as might have been anticipated. Professor Taylor offered a gas theory of the explosion, in which he contended that deflagration would cause a pressure of gas to build up sufficiently quickly in the vaults - the entrance to which was small and through the roof—to cause the explosion. The difficulty with this explanation was in believing that the vaults were well enough sealed as to result in an explosion, when a more gradual forcing up of the cellar roof might more reasonably be anticipated.
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In the absence of a countervailing process, the white dwarf would collapse to form a neutron star, in an accretion-induced non-ejective process, as normally occurs in the case of a white dwarf that is primarily composed of magnesium, neon, and oxygen. The current view among astronomers who model Type Ia supernova explosions, however, is that this limit is never actually attained and collapse is never initiated. Instead, the increase in pressure and density due to the increasing weight raises the temperature of the core, and as the white dwarf approaches about 99% of the limit, a period of convection ensues, lasting approximately 1,000 years. At some point in this simmering phase, a deflagration flame front is born, powered by carbon fusion.
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The main mechanism of detonation propagation is of a powerful pressure wave that compresses the unburnt gas ahead of the wave to a temperature above the autoignition temperature. In technical terms, the reaction zone (chemical combustion) is a self-driven shock wave where the reaction zone and the shock are coincident, and the chemical reaction is initiated by the compressive heating caused by the shock wave. The process is similar to ignition in a Diesel engine, but much more sudden and violent. Under certain conditions, mainly in terms of geometrical conditions (such as partial confinement and many obstacles in the flame path that cause turbulent flame eddy currents), a subsonic flame may accelerate to supersonic speed, transitioning from deflagration to detonation.
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1987 – The Vulcan Point Focal Shaped Charge The need for point-focal penetration led to the development of the Vulcan shaped charge system. After initial experiments using the precursor of the Vulcan to inject liquids which reacted hypergolically with the explosive fill of steel cased munitions, Alford realised that a magnesium cone, which was much manageable than the liquids required for hypergolic reaction, formed a jet which ignited as it was formed. This was quickly shown to provide a simple and reliable means of bringing about relatively gentle deflagration of small and large steel cased munitions with only a low probability of causing detonation. Since then a range of projectiles has been developed for the Vulcan for various other applications.
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A cold-compromised joint in the right SRB failed at launch and eventually allowed hot gases from within that rocket booster to sear a hole into the adjacent main external fuel tank and also weaken the lower strut holding the SRB to the external tank. The leak in the SRB joint caused a catastrophic failure of the lower strut and partial detachment of the SRB, which led to a collision between the SRB and the external tank. With a disintegrating external tank and severely off-axis thrust from the right SRB, traveling at a speed of Mach1.92 at , the Space Shuttle stack disintegrated and was enveloped in an "explosive burn" (i.e. rapid deflagration) of the liquid propellants from the external tank.
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A video on safety precautions at blast sites The largest commercial application of explosives is mining. Whether the mine is on the surface or is buried underground, the detonation or deflagration of either a high or low explosive in a confined space can be used to liberate a fairly specific sub-volume of a brittle material in a much larger volume of the same or similar material. The mining industry tends to use nitrate-based explosives such as emulsions of fuel oil and ammonium nitrate solutions, mixtures of ammonium nitrate prills (fertilizer pellets) and fuel oil (ANFO) and gelatinous suspensions or slurries of ammonium nitrate and combustible fuels. In Materials Science and Engineering, explosives are used in cladding (explosion welding).
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A schematic diagram of a shock wave situation with the density \rho, velocity u, and temperature T indicated for each region. The Rankine–Hugoniot conditions, also referred to as Rankine–Hugoniot jump conditions or Rankine–Hugoniot relations, describe the relationship between the states on both sides of a shock wave or a combustion wave (deflagration or detonation) in a one-dimensional flow in fluids or a one-dimensional deformation in solids. They are named in recognition of the work carried out by Scottish engineer and physicist William John Macquorn Rankine and French engineer Pierre Henri Hugoniot. See also: Hugoniot, H. (1889) "Mémoire sur la propagation des mouvements dans les corps et spécialement dans les gaz parfaits (deuxième partie)" [Memoir on the propagation of movements in bodies, especially perfect gases (second part)], Journal de l'École Polytechnique, vol. 58, pages 1–125.
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'Intuitive, Delaunay has defined intuition as the brusque deflagration of all the reasonings accumulated each day'. The following year, in Cubisme et Tradition (1911) Metzinger writes of the immobility of paintings of the past, and that now, artists permit themselves the liberty of 'moving around the object to give, under the control of intelligence, a concrete representation derived from several successive aspects.' He continues, 'The painting possesses space, and now it also reigns in the duration' ["voilà qu'il règne aussi dans la durée"].,Alexandre Thibault, La durée picturale chez les cubistes et futuristes comme conception du monde: Suggestion d'une parenté avec le problème de la temporalité en philosophie, Université Laval, 2006Timothy J. Clark, Farewell to an Idea: Episodes from a History of Modernism, , 1999, 2001 With motion and time, intuition and consciousness, Metzinger could now claim his art had moved closer to nature, closer to a true, yet subjective, reality.
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A firearm is a barreled ranged weapon that inflicts damage on targets by launching one or more projectiles driven by rapidly expanding high-pressure gas produced by exothermic combustion (deflagration, hence the word stem "fire-") of a chemical propellant, historically black powder, now smokeless powder. In the military, firearms are categorized into "heavy" and "light" weapons regarding their portability by foot soldiers. The subset of light firearms that use kinetic projectiles and are compact enough to be operated to full capacity by a single infantryman (rather than being crew-served) are also referred to as "small arms", a hyponym to which the word "firearm" are often referring in common usage. Such firearms include handguns such as revolvers, pistols and derringers, and long guns such as rifles (of which there are many subtypes such as anti-material rifles, sniper rifles, designated marksman rifles, battle rifles, assault rifles and carbines), shotguns, submachine guns/personal defense weapons, squad automatic weapons and light machine guns.
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