Exploding wire

Gun powders/propcl hints Muzzle blast Recoilless rifle blast Exploding sparks Exploding wires Laser sparks Contained explosions ... 

In a subsequent study (Ref 43), Al, Au, Ft and W wires were investigated to determine the effect of the wire material on the initiation of PETN by exploding wires. Hie wires were exploded by a l-uf capacitor charged to 2000v. The results indicate that favorable wire materials are those into which energy is deposited at a rapid rate. They also have low bp s and heats of vaporization. Heat of oxidation of the wire material plays only a minor role. Different wire materials have different optimum lengths for effecting detonation... 

The following refs are presented in two categories viz, open or unclassified literature (1 to 48) and limited distribution (A to X) 1) W.G. Chace H.K. Moore, Conference on the Exploding Wire Phenomenon,... 

Alqudami, A. and Annapoorni, S. (2007) Fluorescence from metallic silver and iron nanoparticles prepared by exploding wire technique. Plasmonics, 2, 5-13. 

Trifluoroethene at pressures above 14 bar, and possibly below, deflagrates with tenfold pressure rises when initiated by an exploding wire. The tests were on air-free and inhibited commercial material. 

By modifying the procedure described above to explode a wire in the water sphere while the system was under compression, they did attain explosions. Measuring the rebound of the cylinder and the loss of aluminum, they could estimate the work produced by the event. Assuming the maximum energy transfer to the water would occur by constant volume heating to the aluminum temperature, foUowed by an isothermal, reversible expansion, they estimated an efficiency of about 25%. Clearly the exploding wire led to an immediate and effective dispersal of the water. 

Further aluminum pour tests were made in a heavy-wall stainless steel tank fitted with Lucite side windows. The tank was supported on a force transducer and pressure transducers were located on either end. In a test, after the spill, there was a predetermined delay and then the wire was exploded. The aluminum usuaUy had puddled on the tank bottom before the wire explosion and steam bubbles could be seen. The shock from the wire explosion usually collapsed the film and, following this, the aluminum expanded. If the shock were sufficiently energetic, the aluminum soon fragmented and expelled the water from the tank in a thermal explosion. In such cases, the force transducers on the bottom ranged from 5 to 10 N sec. (The exploding wire alone led to impulses around 1 N sec.) Efficiencies of an explosion calculated as indicated above were low. 

Extending this concept, we now consider those experiments which led to molten aluminum-water explosions without the presence of a wet, solid surface. In all of these there was an external shock applied to the system—usually in the form of an exploding wire or a detonator. As presumed by the investigators, these artificial shocks could be very effective in collapsing steam films. 

The exploding wire method involves putting a large amount of energy into a wire suddenly, causing it to explode. If 02 is present, a metal oxide aerosol is produced, whereas particles of pure metal are formed in an inert atmosphere such as helium. Exploding wire generators and their size distribution characteristics have been discussed by Phalen (1972). 

Phalen, R. F., Evaluation of an Exploded-Wire Aerosol Generator for Use in Inhalation Studies, Aerosol Sci., 3, 395-409 (1972). 

This definition applies only to chemical explns and not to physical ones, like "exploding wires . It fails to mention that every expln is accompanied by a thundering noise. This definition is sufficient to clarify the meaning of the term "detonation . A more complete definition of the term "explosion will be given at the end of this section, pD220-R... 

The PETN pellet, B, was initiated by exploding wire assembly, A, which contained... 

R. Friedman, Raketnaya Tekhnika No 1, p 122(1961) (Solid Powders as Sources of Cesium Plasma) 17) R.C. Good Jr, AIAA-Jour, Vol 1, No 6, 1397-1402 (June 1963) ( Destructive Effects of Plasmas Generated by Exploding Wires ) 18) W.G. Chace H.K. Moore, Eds, Exploding Wires ,... 

Plenum Press, NY, Vol 3 (1964), pp 9-22 (Some exptl results of exploding wire research and their application in plasma physics) 118-20 122 (Plasma jet)... 

To investigate these problems, Brossard et al (Ref 13) analyzed data on cylindri-cally diverging detonation waves in various propane/C>2/N2 mixtures contained in divergent sectors. Detonation was initiated with an exploding wire located in the apex of the sector angle. The wave velocity was measured with ionization probes, and the wave structure was observed by means of streak-schlieren and soot-track techniques... 

W.G. Chace H.K. Moore, Exploding Wires, Plenum Press, NY, 1959 ibid, Vol 2, 1962 R.L. Aspden, Electronic Flash Photography, Macmillan Co, NY, 1960... 

E.C. Cassidy et al, Investigations of the Exploding Wire Process as a Source for High Temperature Studies, (NBS Monograph 109),... 

EWPh. Abbr for Exploding Wire Phenomena. See W.H. Richardson, "Exploding Wire... 

EW (Exploding Wire). See EXPLODING BRIDGE WIRE (EBW) in this Vol... 

R, DePersio, "Exploding Wire and Spark Gap Center Initiator for High Explosives",... 

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