Abstracts of papers for

Previous issue vol. 43, no. 4 (2002)

vol. 44, no. 1 (2003)

Next issue vol. 44, no. 2 (2003)

Contents of issue 1, vol. 44

1. E. Włodarczyk: Compression of gas bubble with inertial coating
2. E. Włodarczyk, J. Janiszewski: Analysis of annular detonation wave parameters
3. W.A. Trzciński: Modelling of the shock-to-detonation transition in condensed explosives
4. M. Fusik Z. Koruba: Model of a gyroscope control for an autonomous scanning device aboard of a UAV
5. S. Cudziło, R. Trębiński, W.A. Trzciński: Analysis of the process of acceleration of plates of a model reactive armour
6. A. Jackowski: Investigation of pores collapse in the initial phase of shaped charge liner reduction
7. Z. Koruba: Model of final navigation segment for combat unmanned aerial vehicle

E. Włodarczyk: Compression of gas bubble with inertial coating

The compression problem of the polytropic gas bubble coated by the layer of an ideal incompressible liquid has been solved in the closed form. The simple algebraic formulae, which determine the velocity and pressure fields in the liquid layer, as well as the critical (minimal) radius of the maximally compressed bubble, have been derived. The adiabatic and isothermal gas compressions were examined. The time of the compression process was determined. The general solution of the problem was achieved. The solutions, known in the literature of the similar but simplified problems, result from our solution as particular cases. Key words: two-component media (liquid-gas), gas bubbles compression, detonation, hot-spots, sinters.

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E. Włodarczyk, J. Janiszewski: Analysis of annular detonation wave parameters

Theoretical, qualitative and quantitative analysis of annular detonation wave parameters is carried out. In accordance with the theory of detonation optics, the chemical reaction zone is replaced by the surface of strong discontinuity. This surface is termed the detonation wave front. It was found that in the upper layer of the cylindrical charge, the annular detonation wave propagates with a velocity comparable to the Chapman-Jouguet velocity, and its front is similar to the half-toroidal surface. The radial cumulation of the annular detonation wave parameters occurs in the direct neighbourhood of the charge axis. All the parameters, except for the specific volume, increase to infinity when the charge radius decreases to zero. The phenomena of the dissociation and ionization of detonation product in the cumulation state have been neglected, therefore the results obtained in the direct neighbourhood of the charge axis are of a qualitative character.

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W.A. Trzciński: Modelling of the shock-to-detonation transition in condensed explosives

In the present work, a model describing the phenomena of initiation of detonation in condensed explosive by a shock wave is proposed. The model is adjusted to the system corresponding to the so-called wedge test, which is used for determination of the shock sensitivity of explosives. The system is described, the problem of initiation is formulated and the method of solution of the problem is presented. The results of modelling are compared with the wedge test data given in literature. It is proved that the model proposed can be applied for determination of the rate of chemical decomposition of explosives (the so-called macrokinetic equation).

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M. Fusik Z. Koruba: Model of a gyroscope control for an autonomous scanning device aboard of a UAV

The paper presents a niodel of optical scanning system that can be used as means of detection and tracking of moving ground vehicles. The device can be mounted aboard of a UAV. Kinematic relations between UAV, moving target ami changes in position of an optical axis of scanning device are derived. A model of a gyroscope control as a servomechanism of the scanning device is presented.

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S. Cudziło, R. Trębiński, W.A. Trzciński: Analysis of the process of acceleration of plates of a model reactive armour

In the paper, an experimental and theoretical analysis of the process of acceleration of plates of a model reactive armour is made. Impulse X-ray photography is used for recording the motion of plates launched by the detonation products of a layer of explosive. The theoretical analysis of the driving process is made by the use of a simple model, in which the deformation of plates is taken into account. It is proved that the model proposed can be useful in prediction of the motion of plates of reactive armour.

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A. Jackowski: Investigation of pores collapse in the initial phase of shaped charge liner reduction

The method and experimental results of investigations of shaped charge liner reduction during early stage of collapse are presented in this paper. The liners made of sintered copper with porosity of 6, 8, 10 and 15% were examined. The tests for two variants of loading pressure were carried out. From the research it follows that during early phase of liners collapse, the decay of pores does not occur. Verification of experimental results, on the basis of theoretical model of compression of porous material, was made.

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Z. Koruba: Model of final navigation segment for combat unmanned aerial vehicle

The paper presents the concept of unmanned aerial vehicle (UAV) application to direct destruction of ground targets (radar stations, combat vehicles or tanks). The kinematic model of UAV motion takes into account individual stages of the mission performed by the vehicle, i.e. programme-run flight in target seeking, tracking flight following the target detection and flight in target homing. The law was stated for the control of UAV autopilot.

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