Gases explosion and flammability concentration limits. Series of tests were performed to evaluate the newly developed solidstate fuel air explosives. Lel and uel explained explosive gas the lower explosive limit lel is the minimum concentration of a specific combustible gas required to fire combustion when in contact with oxygen air. Fuel air explosive represent the military application of the vapor cloud explosions and dust explosions accidents that have long. Door frame uses sc joints for better motion thanks will wallace and splinters are individually simulated here but could be optimized for speed vs. Experimental study of fuelair explosive springerlink. Unlike most incendiaries, which contained napalm or phosphorus, the 750 pound cbu55 was fueled primarily by propane. This article describes this ratio and presents an easy way to calculate it when the composition of a fuel is known. I do not know if i accidentally make a fuel air explosive. Pdf ignition of explosive atmosphere by mechanical equipment. Deflagration is an explosion in which the speed of burning is lower than the speed of sound in the surroundings. Normally, when hydrogen and oxygen react, a flame and heat energy are produced. As hydrocarbon fuel vapor and air mixtures burn only at fuel air ratios existing between a rich and lean limit, it becomes necessary to assess the vulnerabiitty hazard of an aircraft fuel tank in terms of those flight parameters causing. Different modes of laminar combustion using a simply tube or by closing the air inlet in a bunsen burner.
Solid state fuel air enhanced blast or thermobaric explosives have very promising features. We recognise the work of the expert group established to steer and advise this project. But by the end of the cold war, the government realized that its whitesonly rule would have to be scrapped, and so its leaders ordered the weapons destroyed and the production facilities dismantled, while holding onto the explosive fuel. A thermobaric weapon, aerosol bomb, or vacuum bomb is a type of explosive that uses oxygen from the surrounding air to generate a hightemperature explosion. Sensitiser provides the heat source hot spot to drive the chemical reaction of oxidiser and fuel. Scope this technical note provides guidance on the identification of hazards, and establishment of safe operating environments and procedures for fuel air explosive fae systems that may be encountered during demining operations in a permissive post conflict environment.
Sciencemadness discussion board fuelair explosives. For what, exactly, only god and the propellerheads in some basement in the pentagon know. A conventional explosive contains both fuel and oxidizer in very close proximity often in the same molecule, which is how it can react so quickly, but this reduces the overall energy. Contentscontinued criteria for nondod explosives activities ae operations and storage on u. In the air force the purpose of explosion proof testing is to insure that equipment used in and around flight vehicles will not cause an explosion if exposed to fuel vapors. Fuelair explosive definition of fuelair explosive by the. Such compounds have a high negative gibbs free energy of reaction, but only a moderate detonation pressure. Both fire and explosion cause dangers to workers, and in many cases the precautions required to prevent an ignition are the same. The flash point of gasoline depending on grade is about 44 degrees f. Jun 01, 2016 a conventional explosive contains both fuel and oxidizer in very close proximity often in the same molecule, which is how it can react so quickly, but this reduces the overall energy. In practice, the blast wave typically produced by such a weapon is of a significantly longer duration than that produced by a conventional condensed explosive.
Previously, bagasse was burned as a means of solid waste disposal. However, ebx types are primarily used to strengthen the blast wave, while tbx are employed to increase temperature and pressure of the explosion. Numerical solutions of the blast wave flow from a spherical explosive charge were obtained using the artificial viscosity technique as employed by oppenheim. In confined spaces, burning may lead to detonation.
The overall package of precautions required will depend on the possible consequences of a fire or explosion. Final may also use tp bulletphysics on similar collisions. Combustible dust an explosive issue air handling systems. The blu82 was developed by the usaf during the vietnam war. Explosive fuel article about explosive fuel by the free. Following in parallel, and using a second stage fueled with liquid hydrogen, was the saturn i block ii vehicle. Lel and uel explained explosive gas projectmaterials. A thermobaric weapon, aerosol bomb, or vacuum bomb, is a type of explosive that uses oxygen from the surrounding air to generate a hightemperature explosion. In many cases where an explosive atmosphere can form, any ignition will cause a fire rather than an explosion. Methane and propane mixed with oxygen or air release in rough order 10 times as much energy as tnt. Chock thesis submitted to the faculty of the virginia polytechnic institute and state university in partial fulfillment of the requirements for the degree of master of science in aerospace engineering approved. Density is an important consideration when choosing an explosive. Ignition of explosive atmospheres by mechanical equipment is a problem in many industries and has led to a large number of incidents including those that have been classified as major accidents. Special fuels that are sprayed into the atmosphere and catch fire on coming into contact with oxygen in air.
Explosives hazardous areas an area in which explosives materialsubstances of explosives ordnance are exposed to the atmosphere such that they require special precautions for the construction and use of equipment in order to prevent ignition of an explosives materialsubstance. On december 27, 1999, interfax reported russian forces were using fuel air explosive bombs in the fighting in chechnya. Army garrisons or installations 810, page 64 subdivision of explosives quantities 811, page 65 interpolation and extrapolation 812, page 65 measuring distance 8, page 65 ammunition and explosives risk 814, page 66 blast considerations 815, page 66. Thermobaric and enhanced blast explosives tbx and ebx.
The flammable range also called explosive range is the concentration range of a gas or vapor that will burn or explode if an ignition source is introduced three basic requirements must be met for explosion to take place. The results show that the effect of the fae explosion at 36 m from the explosion center is definitely more pronounced than that of a tnt charge of the same mass, and solid fuels. The cbu55 was a cluster bomb fuel air explosive that was developed during the vietnam war by the united states air force, and was used only infrequently in that conflict. Fuel cells understand the hazards, control the risks. Da pam 38564 ammunition and explosives safety standards. Results show that the peak overpressure, positive duration, and positive specific impulse increase as the content of. Fuelair explosives hy folks, recently i was trying to create an fireball with an 1 dl of gas and 100200g of dinamite. However, it has been shown that for a gelled based metal enhanced fuel air explosive metal content of approximately 60 %, air blast surpasses the energy density of conventional propylene oxide fuel air explosives. Oct 01, 20 fuel air explosive bombs are not an incendiary or chemical weapon. To investigate the explosion characteristics of the composite explosive, charges with various contents of the tih2 powder are prepared and tested in air explosion experiments. May 30, 2006 moab mother of all bombs gbu43b massive ordnance air blast us military duration. For free running explosives, the density is often specified as the pounds of explosives per foot of charge length in a given size borehole.
A thermobaric weapon is a type of explosive that utilizes oxygen from the surrounding air to generate an intense, hightemperature explosion, and in practice the blast wave such a weapon produces is typically significantly longer in duration than a conventional condensed explosive. The stoichiometric airfuel ratio is an important parameter of fuels. Cg shot of a powerful fuel air bomb over a small and unfortunate empty house. Dust explosions can occur where any dispersed powdered combustible material is present in highenough concentrations in the atmosphere or other oxidizing gaseous medium, such as pure oxygen. Fuel air explosive fae fuel air explosives fae disperse an aerosol cloud of fuel which is ignited by an embedded detonator to produce an explosion.
Chemical initiation of detonation in fuel air explosive clouds abstract the invention relates to the chemical initiation of detonation of a fuel in air fae cloud such as might be used in a minefield breaching system. Fuelair explosive article about fuelair explosive by the. The lfl is the concentration of fuel vapor in air below which combustion is not possible. Explosive weapon effects final report acknowledgements this report and its annexes were authored by the gichd. It mixes with the surrounding air by convection and diffusion during. Then only fuel issues from the tube as shown in the second picture in fig. A fuel air explosive apparatus as set forth in claim 1, wherein said liquid.
In a motor car, petrol in the carburettor is mixed with the right amount of air so that when ignited in the cylinder it explodes. Item description riskestimate distance meters 10% pi 0. Since an adequate supply of oxygen cannot be drawn from the air, a source of oxygen must be incorporated into the explosive mixture. Sep 16, 2015 an explosive mixture of cyclotrimethylenetrinitramine rdx and titanium hydride tih2 is introduced. When designing an engine for a particular fuel, its important to know how much air is needed to completely burn a certain amount of fuel. Cole and 2002 bali nightclub bombings recommended in alqaedas traditional curriculum of explosives training.
A wealth of experience related to the fuel air explosives fae programs exists in the services to assist in material selections and possible formulation guides. Air delivered thermobaric systems were only used outside the city. Described as the most powerful nonnuclear weapon in the u. If the equipment does not cause an explosion, it is said to be explosion. One technique, recommended by the national transportation safety board ntsb, is to maintain sufficient fuel in the center wing tanks of transport aircraft to limit the liquid fuel temperature rise and evaporation, thus keeping the vapor fuel air ratio below the explosive limit. Jul 25, 2003 the flash point is the minimum temperature of a liquid where it will give off sufficient vapors to form an ignitable mixture in air. Some commercial explosives with high fuel content may readily ignite and burn. They can combine superior air blast impulse with metal fragmentation and metal acceleration effects. Is gasoline considered an explosive or a flammable liquid. Energetic measures of effectiveness of aluminized explosives.
Full text of fuel air explosive systems see other formats technical note 09. Tp5 shape collision used in procedural wood fracturing. Other explosives with superior characteristics were also developed. But because of their wide area effects, which make them highly indiscriminate weapons, human rights watch believes fuel air. Experiments on an explosion of a fuelair explosive fae are carried out in open field, and comparative analyses between solid fuels, liquidsolid fuels of different recipes, and tnt of the same mass are applied. To speed up the rate of combustion, it is necessary to disperse the oil in air before ignition. Blu96b 2000lb fuelair explosive fae ii bomb youtube. Thermobaric weapon project gutenberg selfpublishing. Such a cloud is most likely to burn as a deflagration, but the most severe explosion is a detonation that. Use of a mixture of tnt and amrnonium nitrate, called amatol became widespread to relieve the shortage of tnt. Cliff weapons systems division aeronautical and maritime research laboratory dstotr0796 abstract 3nitro1,2,4triazol5one nto is an explosive ingredient under investigation as a potential insensitive replacement for rdx in explosive formulations. Introduction to explosives for official use only c4.
However, due to an enhanced impulse the blast effect of such explosives. The fuel air bomb is one of the most wellknown types of thermobaric weapons. As with all explosive materials, chemical composition is only a starting point in discussing performance. Pdf solid state fuelair enhanced blast or thermobaric explosives have very promising features. If the concentration of the gas is below the lel value, the mix between the gas itself and the air is. A fuel air explosive apparatus as set forth in claim 1, wherein said standard sized, plastic beverage bottle is of a size selected from the group consisting of 0.
Verifying performance of thermobaric materials for small to medium caliber rocket warheads pdf. Review of methods for calculating pressure profiles of. There was no fireball butt presure,destruction and noise was unproportionall with the amount of explosive. Gases and compressed air air, lng, lpg and other common gas properties, pipeline capacities, sizing of relief valves related documents acetone thermophysical properties chemical, physical and thermal properties of acetone, also called 2propanone, dimethyl ketone and pyroacetic acid. Fuelair explosive fae oder fuelair bomb, umgangssprachlich. A component of the system is adapted to carry fuel to the breaching site and is also adapted to carry a compatible. Anfo and waterbased explosives such as water gels and emulsions are more difficult to ignite in the open. Tp for physics and debris, vray for final render, and ffx for any fire, smoke and dust. Transition to detonation in fuelair explosive clouds.
Understand the hazards, control the risks page 5 of 32 health and safety executive how fuel cells work 5 a fuel cell is a device for harnessing the energy liberated when hydrogen, or a hydrogenrich fuel, reacts with oxygen to produce water. Fuel tank safety enhancements of large transport airplanes. A highimpulse thermobaric bomb hit, also known as fuel pump, fuel pump, fuel air explosive fae or fax, a weapon of heat and pressure or vacuum pump is a liquid container volatile or high pressure gas models an explosive mixed with finely powdered and usually two separate explosive charges. Fuel a chemical that reacts with oxygen to produce heat. They can combine superior air blast impulse with metal fragmentation and acceleration effects, thus enabling to create ordnance with improved. Fuelair explosive definition of fuelair explosive by. Some aspects of blast from fuelair explosives sciencedirect. Thermobaric and enhanced blast explosives tbx and ebx since the differences between tbx and ebx are usually small, these two terms are therefore often interchangeably used in the literature. Fuelair explosive how is fuelair explosive abbreviated. Pdf solid state fuelair explosives robert weinheimer. Fuel tank safety enhancements of federal aviation large transport airplanes administration 57th annual international air safety seminar november 1518, 2004 shanghai, china daniel i.
The editors of the report were samuel paunila gichd and n. Chemical initiation of detonation in fuelair explosive clouds. Everyday fire and most controlled explosions are examples of deflagration. Nov 12, 2000 the largest air deliverable conventional weapon in the world is a fuel air explosive. But in a very diffuse reaction even if it efficiently detonates in the air. An explosive functions either by detonation rate of decomposition faster than the speed of sound or deflagration very rapid burning. Eventually, picric acid was accepted all over the world as the basic explosive for military uses. The flame propagation velocity is less than 100 meters per second usually much lower, and the overpressure is less than 0. Fuel air explosives also called thermobaric explosives weapons with organic fuels have been known since the 1960s. Around 1902, the germans and british had experimented with trinitrotoluene tnt, first prepared by wilbrand in 1863. To evaluate hydrogen safety the following set of issues should be addressed for each of the applications hydrogen release, mixing, and distribution thermal, pressure, and missile effects from h 2 fires and h 2air cloud explosions mitigation techniques for detection, dilution, and removal of hydrogen. Fuel air aka thermobaric or novel explosives contain more fuel and rely on mixing it finely with the air and using atmospheric oxygen as the oxidizer, so. Solid state fuel air ebx and tbx enhanced blast and thermobaric explosives have very promising features. Explosive atmospheres classification of hazardous areas.
Hazardous materials hazmat certification and mobility. Guidelines for identifying hazardous areas identify a. Transition to detonation in fuelair explosive clouds sciencedirect. A dust explosion is the rapid combustion of fine particles suspended in the air within an enclosed location. A highimpulse thermobaric bomb hit, also known as fuel pump, fuel pump, fuelair explosive fae or fax, a weapon of heat and pressure or vacuum pump is a liquid container volatile or high pressure gas models an explosive mixed with finely powdered and usually two separate explosive charges. The equipment is tested by operating it in an explosive fuel air mixture. The fuel air explosive fae is one of the bestknown types of thermobaric. With few exceptions, denser explosives give higher detonation velocities and pressures. An explosive is a chemical material that is capable of extremely rapid combustion resulting in an explosion or detonation. Air explosion characteristics of a novel tih 2 rdx composite. Review of methods for calculating pressure profiles of explosive air blast and its sample application by jeffrey m. How air fuel ratio can be diagnosed and monitored with the help of air. From similarity considerations, the turbulent mixing rates should scale with the explosion length and time scales.
Russian fuel air explosives vacuum bombs human rights watch. The ufl is the fuel vapor concentration above flammable materials can cause fires and explosions if they are not handled properly. The accumulations of combustible dust must be removed. Fuel air explosives hy folks, recently i was trying to create an fireball with an 1 dl of gas and 100200g of dinamite. Experiments on an explosion of a fuelair explosive fae are carried out in open field, and comparative analyses between solid fuels, liquidsolid fuels o. Sensitisers are generally small air bubbles or pockets within the explosive.