Voitenko compressor

In 1965 a Russian scientist proposed that the shaped charge originally developed for piercing thick steel armor be adapted to the task of accelerating shock waves. The resulting device, looking a little like a wind tunnel, is called a Voitenko compressor.

The Voitenko compressor initially separates a test gas from a shaped charge with a malleable steel plate. When the shaped charge detonates, most of its energy is focused on the steel plate, driving it forward and pushing the test gas ahead of it. Ames translated this idea into a self-destroying shock tube. A 66-pound shaped charge accelerated the gas in a 3-cm glass-walled tube 2 meters in length. The velocity of the resulting shock wave was a phenomenal 220 000 feet per second. The apparatus exposed to the detonation was, of course, completely destroyed, but not before useful data were extracted. [http://history.nasa.gov/SP-440/ch6-15.htm] [http://www.globalsecurity.org/military/systems/munitions/bullets2-shaped-charge.htm] In a typical Voitenko compressor, a shaped charge accelerates hydrogen gas which in turn accelerates a thin disk up to about 40 km/s. [http://www.nas.nasa.gov/About/Education/SpaceSettlement/Nowicki/SPBI134.HTM]

These devices produce extremely high heat and pressure conditions exceeding 1,000,000 K ,and are hence suited for nuclear fusion applications. The UTIAS explosive-driven-implosion facility was used to produce stable, centered and focused hemispherical implosions to generate neutrons from D-D reactions.The simplest and most direct method proved to be in a predetonated stoichiometric mixture of deuterium-oxygen.The other successful method was using a miniature Voitenko-type compressor,where a plane diaphragm was driven by the implosion wave into a secondary small spherical cavity that contained pure deuterium gas at one atmosphere. [http://handle.dtic.mil/100.2/ADA121652] [http://adsabs.harvard.edu/abs/1982edhi.book.....S] In brief, PETN solid explosive is used to form a hemispherical shell (3mm to 6mm thick) in a 20-cm diameter hemispherical cavity milled in a massive steel chamber. The remaining volume is filled with a stoichiometric mixture of (H₂ or D₂ and O₂). This mixture is detonated by a very short thin exploding wire located at the geometric center. The arrival of the detonation wave at the spherical surface instantly and simultaneously fires the explosive liner. The detonation wave in the explosive liner hits the metal cavity,reflects, and implodes on the preheated burnt gases,focuses at the center of the hemisphere (50 microseconds after the initiation of the exploding wire) and reflects, leaving behind a very small pocket (1mm) of extremely high-temperature, high-pressure and high density plasma.

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