Wyniki wyszukiwania - BazTech

1

Semi Active Noise Damping by Vacuum Packed Particles

Rutkowski M., Zalewski R.

Machine Dynamics Research

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2012

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Vol. 36, No. 3

81-88

EN

This research is the next stage of research related to extraordinary features of Special Granular Structures. Some properties of granular structures, e.g. the changing of structure of the material, once it is submitted to internal underpressure in a sealed container, led the authors to believe that the acoustic properties may also change with pressure. Performed research regarding material sound absorption of investigated granular structures shows new potential possibilities of their application and confirms, that one can control acoustic properties of such structures.

2

Six Parameters Rheological Model for Special Granular Structures

Zalewski R., Skoniecki Ł.

Machine Dynamics Research

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2011

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Vol. 35, No. 3

107-116

EN

The main objective of presented paper is to propose a mathematical model capable to capture the real response of the special granular structures subjected to cyclic loading. ABS filled cylindrical form was subjected to triangular excitation rule with constant frequency and various underpressure values. Numerical simulations are provided that enabled for verification of proposed model and real behavior of the granular conglomerate. Proposed model is suitable to describe a mechanical response of SGS on applied kinematical excitation.

3

Mathematical Model for Special Granular Structures

Zalewski R., Skoniecki Ł.

Machine Dynamics Research

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2011

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Vol. 35, No. 2

98-107

EN

The main objective of presented paper is to propose a mathematical (rheological) model capable to capture the real response of the special granular structures subjected to cyclic loading. ABS filled cylindrical form was subjected to triangular excitation rule with constant frequency and various underpressure values. Detailed analysis of the numerical model's response is provided and rheological model, capable to capture correctly the real behaviour of the special granular structures is proposed.

4

Experimental Analysis of Beam Vibrations Damping with the Special ABS Granular Structure

Zalewski R., Bajkowski J. M.

Machine Dynamics Research

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2011

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Vol. 35, No. 3

98-106

EN

The analysis and generalization of experimental data obtained for the steel beam covered with hermetic sleeve with granular material, were used to determine the influence vacuum effect on beam vibrations. Increasing the underpressure value leads to clustering and interlocking of the grains, thus the so called jammed state and force chains occur. Experimental results confirmed that the granular-filled vacuum structure can be used for easily controlled significant increase in damping ratio of the system.

5

Analysis of special granular structures response on the external loading

Zalewski R.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

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2010

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z. 4/80

111-118

EN

This paper concerns problems related to complex response of Special Granular Structures (SGS) on applied external loading. Typical experimental results acquired from uniaxial compression tests are presented. For the most part influences of underpressure and strain rate are discussed. Universal dependencies between determined Young modulus values and underpressures and proof stresses vs. underpressures are introduced. Finally complex behavior of SGS is analyzed basing on experimentally obtained surfaces: E=f(V,p) and k=(V,p).