Anatoly Mikhailov, Deputy Chief Designer, Head of the Gas Dynamics Research Section, Russian Federal Nuclear Center |
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To continue a series of publications dedicated to the Russian Federal Nuclear Center All-Russia Research Institute of Experimental Physics (RFYaTs-VNIIEF), and its role in the advanced development of conventional weapons, we shall focus on the Institute s gas dynamics research which constitutes a major aspect of warhead research development. The research in the field of gas dynamics, together with theoretical projections and computer modeling, help determine warhead physical configuration and its basic design. |
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he VNIIEF Gas Dynamics Research Center is known for: a staff of over a thousand researchers, engineers and workers of various specialities, including ten Doctors and over fifty Candidates of Science (Technology), as well as members of Russian and foreign academies; a world-renown research school in substance behavior under intensive dynamic loads and extremely high pressures and temperatures; an independent center of technological research and development in explosive compounds. The Center is directly linked with pilot and series-production facilities; research in detonation physics, shock wave phenomena, and other explosive processes by multiple laboratory techniques and facilities mostly developed by VNIIEF researchers and designers; detonation test sites and mobile measurement systems adapted to a wide range of tasks related to weapon tests.
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Multichannel recording of detonation process |
In the late 1980s and through the early 1990s, VNIIEF launched the development of conventional munitions and, in cooperation with traditional developers of warheads and weapons, has achieved significant results in the improvement of weapon systems. These results have been achieved due to the following principles pursued by the Institute: 1. The research and development of warhead technology has been concentrated at a single enterprise. The Experimental Physics Research Institute has the capacity to perform all the essential stages of its research and development: the theoretical evaluation and estimation of physical configuration, capability assessment, and target success ratios, as well as the design, experimental development, manufacturing and tests of its prototypes. And finally, the introduction of complete systems into series production. 2. A thorough understanding of the gasdynamic processes has been achieved due to the ability to evaluate and model them using digital codes based on vast libraries of parameters describing the equation of state, as well as physical and mechanical properties of construction materials, explosives and detonation byproducts. The computational modeling and experimental validation of estimates are integrated into an iterative process. 3. The ability has been achieved to precisely control explosion frontage and dynamics, destruction action and concentration of the energy of explosion according to a specified algorithm. The basic technologies of the Institute s Gas Dynamics Research Center used for conventional warhead development include: 1. High-speed photography and photochronography based on both traditional optomechanical cameras and optronic recorders. 2. Pulsed radiography, which is one of the most advanced methods used to conduct experiments in the field of gas dynamics. VNIIEF maintains the most diverse and powerful inventory of radiography equipment in Russia. As a rule, all this equipment from comparatively soft X-ray installations of about 1 MeV (used to diagnose shock and detonation wave fronts), to powerfully charged belatrons and linear electron accelerators producing tens of MeV (these are capable of transilluminating over 200 mm of lead within approximately 0.1 us), has been developed and solely manufactured by VNIIEF. Characteristics of several major radiography installations of the VNIIEF Gas Dynamics Research Center are presented in Table 1. The registration of X-ray images is carried out by both traditional X-ray film recorders and unique multiframe optronic recorders, as well as by recorders in which the sensitivity of X-ray film increases at certain instants of time, while this or that process is being examined. To diagnose fragmentation fields, cumulative jets and their effect on targets, a wide-screen system has been developed with a maximum hit registration area of 10 m2.
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Stvol-series detonation impact stands |
Techniques of X-ray image digitization make it possible to determine the volume of objects, their shape and substance density distribution; detect cavities and cracks and, using a series of images, measure the mean velocities of impacting elements and restore three- dimensional geometry. 3. Multichannel measurements of time intervals and analog signals (with the number of measurement channels amounting to several hundreds) can be made by means of modern digital recorders based on computer technologies, and unique optronic recorders with signal modulation by miniature Kerr gates. These recorders are adapted to various fiber-optic, electromechanical, piezo-electric, piezo-resistive and other sensing systems. All of the above-mentioned techniques can be combined with standard methods adopted for warhead tests. 4. The Stvol-series detonation impact facilities are part of the VNIIEF Gas Dynamics Research Center. Based on the use of energy from distributed HE charges detonated in the explosion-containing volumes of detonation chambers, they are designed to produce high-intensity mechanical loads on missile and artillery weapons under development. These chambers can withstand loads of up to 104 g and can accommodate separate elements and structures of missile and artillery weapons with a maximum weight of 400 kg and a maximum caliber of 410 mm. To avoid going into a detailed description of the VNIIEF experimental gas dynamics research facilities, we shall outline the main trends and results of VNIIEF activities in the development of warheads for conventional weapon systems. They are: smart blast-fragmentation warheads which, according to a specified algorithm, can compensate for a miss and a type of target by changing the characteristics of fragmentation field: the speed, direction, shape and mass of fragments. Some warheads have up to eight detonation modes. Their fragmentation field energy in a specified direction can be increased 2.5 times compared to that of isotropic ones; screen-type blast-fragmentation warheads featuring the speed distribution of fragments from 0.1 to 2.0 km/s; adaptive systems for the active protection of tanks and weapon systems; high-capacity programmable detonation piezo-electric generators; systems making it possible to accelerate clusters of submunitions in the desired direction to a speed over 12 km/s; systems for detonation-free destruction and the de-activation of ammunition and unidentified explosion-hazardous objects; vehicles for safe removal of explosive material; explosion-proof containers capable of withstaning an explosion of up to 150kg TNT for the transportation and detonation of ammunition and other explosive materials. Such containers are being developed not only for Russia, but also custom-produced on requests from some U.S. laboratories; improvement of a large number of shaped-charge monoblock and tandem warheads which will increase their piercing capacity by 20 to 80 percent and of a series of projectile-forming warheads for weapon systems increasing their combat capabilities by 30 to 200 percent, and providing the stability and requisite flight parameters of impacting fragments over a distance of up to 200 m. The vast experience of the VNIIEF Gas Dynamics Center is a necessary institution under conditions of a proposed nuclear test ban. The Institute can serve as the basic facility for the development and tests of Russian conventional warheads. We are also open for international cooperation in otherl fields. Table 1. VNIIEF Radiography Installations
Installation |
Eg max, MeV |
t, us |
Number of frames |
Pulsed transillumination capacity, lead, mm |
BIM 234 |
70 |
0.2 |
1 - 10 |
180, two projections |
BIM 234.2000 |
70 |
0.2 |
1 |
220 |
BIM 234.3000 |
70 |
0.2 |
1 - 10 |
260 |
ERIDAN-3 |
1 |
0.3 |
1 - 2 |
60 mm (steel) |
GONG |
1 |
0.01 |
1 |
50 mm (steel) |
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