Mechanics

2006, No. 4

I.K. Gimaltdinov

TWO-DIMENSIONAL AND NON-LINEAR EFFECTS IN THE BUBBLE DETONATION

Explosion of screen of a finite size in a volume of fluid under pressure impulse is studied in two-dimensional formulation. Results on dynamics of origin and collapse of one-dimensional detonation waves in an inhomogeneous volume bubble fraction system due to non-linear effects of pressure waves propagation through the boundary of inhomogeneity are presented.

A.V. Klyukanov

AN EXPERIMENTAL STUDY OF MECHANICAL CHARACTERISTICS OF BRITTLE FRACTURE

The present study deals with experimental mechanical characteristics of brittle fracture (specific for ammoniacal saltpeter). In the work the critical values are experimentally obtained, characterizing fracture of specimens, which give for compressing stresses —2,41 MPa, for strains —0,102 and for Young’s Modulus — 25,5 MPa. Statististical processing of obtained experimental data is carried out. Measurement errors are given for compressing stresses —6,3%, for strains — 12% and for Young’s Modulus— 11,4%.

Y.N. Radayev

ON SYMMETRY GROUPS OF THE PLANE-STRAIN EQUATIONS OF THE MATHEMATICAL PLASTICITY

Group analysis of the system of partial differential equations of plane-strain plastic equilibrium is given. The static equilibrium equations are represented in the stress principal lines co-ordinate net (isostatic net). Their symmetry groups are obtained. The Lie algebra is studied. The group invariant solutions of the system are shown can be expressed via the elementary functions only.