 G. Szefer:
Dynamics of elastic bodies undergoing large motions and unilateral contact
 E. Włodarczyk:
Brisance of the high explosives
 Z. Dżygadło, I. Nowotarski, A. Olejnik:
Nonlinear, regular and chaotic vibrations of a plate in supersonic flow
 S. Cudziło, K. Jach, M. Mroczkowski, A. Sarzyński, R. Świerczyński, R. Trębiński:
Experimental verification of a theoretical model of the shaped charge jet formation process
 T. J. Hoffmann and B. Niechciałkowska:
Strong discontinuity waves in extended phenomenological electrodynamics
 R. Nawrowski:
Air or SF_{6} insulated heavycurrent busways
 Z. Łęgowski:
A new formulation of the local reflection theory of an oblique shock wave at a rigid wall
 F. Ozek:
Estimation of the range for free space optical links between mobile terminals
 R. Dulski:
Computer faceted thermal target model
 W.A. Trzciński, J. Paszula:
Confined explosions of high explosives
Brief Notes
 J. Cabański:
Generalized exact method of analysis of free and forced
oscillations in the nonconservative physical system
 G. Szefer:
Dynamics of elastic bodies undergoing large motions and unilateral contact
 In the paper, a general description and analysis of motion of elastic bodies experiencing
large displacements and finite strains in terms of unilateral frictional contact will be presented.
Displacements are resolved into displacements due to deformation and displacements due to
rigid body motion. The paper consists of two main parts: the first one deals with the coupling
of rigid body motion and deformation. Using the principles of momentum and angular momentum,
the set of the governing equations of the dynamical system will be derived. The second part deals
with the statement and with the characteristic features of a general dynamic large displacement
contact problem. We end the presentation with some concluding remarks, perspectives and open problems.
Contents
 E. Włodarczyk:
Brisance of the high explosives
 The essential survey of the literature data, concerning the brisance of high explosives (HE)
has been made in this paper. It is confirmed that the quantitative criteria of the theoretical
estimate of the HE brisance proposed in the scientific literature are based on several assumptions,
which are contradictory to the real course of the explosion phenomenon, and therefore
they are erroneous. These criteria must not be applicated in the engineering practice.
The reflection process of the detonation wave from the inertial rigid partition was used
in order to derive the new formula describing the relative brisance of the HE. Moreover,
the brisance of numerous commercial explosives and the military ones has been analysed, too.
The results, presented in this paper, are confirmed by experimentally gained data.
Contents
 Z. Dżygadło, I. Nowotarski, A. Olejnik:
Nonlinear, regular and chaotic vibrations of a plate in supersonic flow
 Aeroelasticity of surface structures in supersonic flow is a domain which involves various
linear and nonlinear vibrations, static and dynamic instabilites and limit cycle motions
(cf. [14]). Various types of bifurcations and regular or chaotic motions can appear
depending on the values of parameters of the system under investigation [311]. In this paper,
nonlinear bending vibrations of a plate of finite length and infinite width in supersonic flow
are considered under the assumption that a nonlinear inplane compressing force is acting
in the plate. The dynamic pressure difference produced by the plate motion in gas stream is
determined on the basis of the potential theory of supersonic flow [1, 2]. Finally, we obtain
a nonlinear partial integrodifferential equation describing the motion of the structure under
investigation. The solution of this equation is obtained in the form of a series of normalised
eigenfunctions of the selfadjoint boundaryvalue vibration problem of the same plate in the vacuum.
Making use of the Galerkin method, we then obtain a set of nonlinear ordinary differential equations
which can be analysed by means of numerical methods. Types of bifurcations occurring in the problem
are investigated, limit cycles of selfexcited vibrations and regions of regular and chaotic motions
can be determined.
Contents
 S. Cudziło, K. Jach, M. Mroczkowski, A. Sarzyński, R. Świerczyński, R. Trębiński:
Experimental verification of a theoretical model of the shaped charge jet formation process
 Experimental verification of a theoretical model of the shaped charge jet formation process
has been performed. The model is based on the numerical solution of the equations of mechanics
of continuous media. It was described in earlier works of the authors. In the first stage of its
experimental verification, flash radiographs of the shape of collapsing liner were taken and then
compared with the results of modelling. After that, theoretical and experimental relations between
detonation parameters of explosives, case material, wave shaper diameter, liner shape and jet
characteristics were investigated. Validity of the theoretical model was assessed on the basis of
comparison of the calculated and experimental jet tip velocities.
Contents
 T. J. Hoffmann and B. Niechciałkowska:
Strong discontinuity waves in extended phenomenological electrodynamics
 In the paper the description of discontinuity of the electromagnetic field in the continuum
medium in terms of the extended electrodynamics in considered. The classical field theory based
on the analytical LagrangeHamilton methods has been used as a formal apparatus.
The classical theory of discontinuity waves is applied to the description of the discontinuity
of the field. Dynamics of the electromagnetic field is expressed in terms of the Lagrange equations
of motion in the linear approximation.
Contents
 R. Nawrowski:
Air or SF_{6} insulated heavycurrent busways
 In the paper the method of calculation of the eddy current losses, the temperature,
the electrodynamics forces, material and energetic optimization of the shape of busways
system with air and SF_{6} insulation are presented. The method discussed takes into
consideration coupling between the electromagnetic field and the thermal field. The method is
based on the numerical solution of equations joining the temperature and the eddycurrent losses.
The method of successive approximations and numerical optimizations are used to solve the equations.
In this paper it is assumed that the analyzed system is linear and infinitely long in the direction
of the conductors.
Contents
 Z. Łęgowski:
A new formulation of the local reflection theory of an oblique shock wave at a rigid wall
 A complete solution to the local theory of the shock wave reflection at an inclined wall
has been obtained for the first time in two particular regions. One is the region near
the Mach stem confluence S point with the wall and the other in the vicinity
of the triple point T of an irregular shockwave configuration. The correct lines
of regularirregular transitions have been established for the selfsimilar reflection problem
in shock tubes. The solutions for all shockfronts geometry have been obtained in the vicinity
of the triple point, which are in agreement with the results of experimental measurements.
In all the region of interaction the backwardreflected shock waves have been obtained for incident
waves of arbitrary intensity. It has been formulated the hypothesis concerning the regularirregular
transition of weak shock waves, as a result of disintegration of an arbitrary discontinuity formed
at the terminal stage of regular reflection.
Contents
 F. Ozek:
Estimation of the range for free space optical links between mobile terminals
 The motivation being the modern trend towards mobile communication, the maximum estimated ranges
of communication have been numerically evaluated for free space optical links between mobile
onsea terminals, for different bit rates and atmospheric conditions. An analysis of possible sources
of noise, by day and night, is given. The advantages of a wide angle elliptic beam of medium power
diodes at the transmitter and a fourquadrant detector at the receiver are emphasized. The effect of
the size and position of the laser spot formed on the detector is pointed out.
Contents
 R. Dulski:
Computer faceted thermal target model
 The paper proposes a computer Faceted Thermal Target Model (FTTM) describing target's radiative
properties in the infrared spectral region. The model is intended for simulation of a target in
analyses of the influence of thermalscene conditions on the possibilities of target detection by
a thermodetection system. This is a model describing the target as a set of facets. The set of data
for the model requires information on the shape and dimensions of the target as well as on distribution
of temperature and emissivity coefficient of its surface. The model enables to determine emission of
radiation from the target surface for various directions of detection, which makes it possible
to obtain the data necessary to design devices for infrared recognition, with a limited application
of costly experimental investigations.
Contents
 W.A. Trzciński, J. Paszula:
Confined explosions of high explosives
 In the present paper, effects of turbulent combustion of the detonation products of high explosives
in confined explosions are studied. Explosions of TNT, TNT/RDX and the mixtures of these explosives
with Al are investigated in a steel chamber of 150liter volume. The chamber is filled with nitrogen
or air under normal conditions. Overpressure histories are recorded at the chamber wall. The dependence
of the mean overpressure on the loading density of TNT is determined. This dependence is used to
determine the TNT equivalent of explosives tested for confined explosions. On the basis of the measured
overpressure histories and the results of thermochemical calculations, the rate of energy release and
final heat effects of combustion of the detonation products in air are also estimated. Finally,
the degree of afterburning of the detonation products is calculated for explosive mixtures tested.
Contents
 J. Cabański:
Generalized exact method of analysis of free and forced
oscillations in the nonconservative physical system
 In this paper, the fundamental problems in the generalized exact form used for the analysis
of oscillations in composite physical systems, are presented. To these generalized problems
belong such as: separation of variables in the complex Hilbert space, orthogonality
of the eigenvectors of boundaryvalue problems, influence of the initial conditions
and forced oscillations. The generalizations have been presented in the operator forms.
In the case of real physical systems, it is necessary to transform the operator forms into
suitable scalar ones. The presented approach is an essential extension of the method
of separation of variable applied to the linear system of differential equations.
Contents
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