Issue 2/2008

UDK 532.517.4+519.63
SHOCK WAVE INTERACTION WITH AN OBLIQUE INTERFACE BY / A. N. Razin // P. 3

A solution has been obtained for interaction between a planar shock wave and an oblique interface separating two gases with different densities. The passage through the interface of a shock wave approaching both from the light and the heavy gas is considered. Test cases are suggested that can be used with 2D gas-dynamic codes to study methodological issues of interactions between a shock traveling over a skew mesh and an interface.

UDK 532.517.4+519.63
INVESTIGATION OF TURBULENT MIXING DEVELOPMENT IN THREE-LAYER GASEOUS SYSTEMS WITH AN OBLIQUE INTERFACE BY / N. V. Nevmerzhitsky, A. N. Razin, E. D. Senkovsky, V. I. Dudin, E. A. Sotskov, A. A. Nikulin, L. V. Tochilina, O. L. Krivonos // P. 12

Results are presented of an experimental study focused on turbulent mixing developing at interfaces in three-layer gaseous systems after the passage of a steady shock wave. The experiments were conducted using an air shock tube with a 120x40 mm cross-section, Mach number of the incident shock wave was M~1.3. Turbulent mixing development behavior at the following interfaces in the system was studied: Air – He – SF₆, Air – SF₆ – Air and Air – SF₆ – He. In each series of tests, one of the interfaces was parallel to the incident shock front, and the other was oriented at a specific angle to the front. This experimental geometry ensured turbulent mixing development in 2D flows.
New experimental data were obtained on turbulent mixing development behaviors in 2D flows. These data are very useful for understanding the physics of this phenomenon, for the verification of physical models and numerical techniques. A brief theoretical analysis of the observed flow is given.

UDK 539.17
ELEMENTS OF THE SIMILARITY THEORY FOR NON-STATIONARY UNIFORM SYSTEMS IN ONE-VELOCITY NEUTRON KINETICS / N. B. Babichev, I. V. Lutikov, A. A. Sevastyanov // P. 18

The universality property (independence of the medium nuclear-physical characteristics) has been proved for non-stationary solutions of one-velocity neutron transport equation in uniform systems. On this basis, similarity formulae have been derived for eigenfunctions. The material presented in this paper, in whole, represents a branch of the similarity theory in neutron kinetics.

UDK 539.17
PECULIARITIES OF ONE- VELOCITY NEUTRON KINETICS IN OPTICALLY- THICK UNIFORM SYSTEMS AND A SOLUTION TO MILNE’S PROBLEM IN QUASI- STATIONARY FORMULATION / N. B. Babichev, I. V. Lutikov, V. P. Neznamov // P. 21

The following unique property of the Kinetic equation solutions has been discovered as a result of conversion to a dimensionless phase space: within a uniform system with infinite optical thickness, their spatial and angular terms are independent of the nuclear-physical characteristics of the matter in the system. Based on this statement and on the known solution to Milne’s problem for an inert medium, a new (quasi-stationery) solution to Milne’s problem has been derived for an arbitrary medium. This is highly valuable, because quasi- stationery solution is the correct solution for a neutron-multiplying medium.

UDK 539.17
FEATURES OF NEUTRON SPATIAL DISTRIBUTION NEAR INTERFACES / N. B. Babichev, A. A. Sevastyanov // P. 32

Analytical formulae have been derived for calculations of eigenfuction gradients in the one-velocity integral equation for neutrons near interfaces between optically thick systems consisting of substances with different nuclear-physical properties. It follows from these formulae that eigenfunction gradients diverge logarithmically at interfaces. Similar divergences take place in case of stepwise neutron sources acting in the system (Q = const within a specified spatial zone and Q = 0 outside this zone) in optically thin systems.

УДК 534.222.2; 531.3
X-RAY DIFFRACTION STUDIS OF THE PHASE TRANSFORMATION OF SHOCK COMPRESSED α-QUARTZ / L. A. Egorov, D. A. Volkov, I. N. Govorunov, V. V. Mokhova, M. N. Pavlovskii // P. 38

First results from X-ray diffraction structural study shock compressed α-quartz et pressure ~ 22 GPa are presented. An analysis of the date leads to the conclusion that crystal of α-quartz compresses to specific volume V = 0.304 cm³/g keeping its initial hexagonal structure. Further compression accompanies the transformation from hexagonal structure to structure of rutile-type with variable ratio a/c of a parameters of tetragonal prism.

УДК 585.512
3D MODEL OF CONCENTRATED SHELL WITH MAGNETIC FIELD / S. A. Kholin, V. I. Nechpai, L. F. Potapkina, S. G. Smirnov // P. 42

The effects of 2D and 3D capsule irradiation asymmetry  on thermonuclear mixture compression and ignition are compared using the model of concentrated shell with magnetic field.