Wyniki wyszukiwania - BazTech

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Numerical comparison of blast waves generatedby cylindrical explosive charges with varying shapes and materials

Panowicz R., Trypolin M., Konarzewski M.

Computer Assisted Methods in Engineering and Science

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2016

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Vol. 23, no. 4

206--212

EN

A significant influence of explosive charge geometry is frequently observed during experimental testing.In this paper, the effect of explosive charge shape, along with its material properties, on the generatedblast waves is studied. The FEM analysis was conducted for six different explosive materials and threedifferent cylindrical shapes, with geometrical proportions of length L to diameter D varying between 2, 1and 0.25 and constant charge mass. We found that the blast wave generated by detonation is susceptibleto shape changes. However, the different explosive materials were influenced by the charge shape in almostthe same way, with only insignificant differences resulting from the material properties.

2

Numerical and experimental study on soil penetration with the use of vibrating head

Małek E., Miedzińska D., Bogusz P.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 72, nr 1

23--31

EN

Purpose: The aim of the paper is to present the numerical modeling of soil penetration with the steel cylinder and experimental research of deflection of elastomer pillows in vibrating head. Design/methodology/approach: Simulations were performed using LS-DYNA package with two different methods to represent soil: a hybrid approach combining typical Lagrangian elements with Smoothed Particle Hydrodynamics (SPH) particles and Arbitrary Lagrangian-Eulerian (ALE) formulation. The experimental study was performed during work of the vibrating head using optical measuring methods. Two black and white cameras of high definition (1280x800) Vision Research Phantom V12 were used. Findings: As a result of conducted numerical simulations the behavior of the soil under condition of dynamic interaction of the steel element was reflected on the base of experimental research the maximum deflection of pillows was determined. Research limitations/implications: The modeling will be used to study the coupling of steel cylinder – soil for different soil properties and different speeds of load and its correctness was prooved. The presented results of experimental studies will be used for developing a construction of MRE regulator for vibrator resonance control. Practical implications: Presented investigations are the part of a new vibrator construction development in which the modeling of soil and its interaction with the steel-like elements will be crucial for obtaining satisfactory results as well as a presented experiment. Originality/value: New solutions to enhancing effectiveness for coupled mechanical systems can be achieved by using so called “smart” materials that have one or more properties that can be significantly changed in a controlled way by external stimulation.

3

ALE method in the fluid-structure interactions

Křen J., Žán J.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2002

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z. 19

101-104

EN

The paper deals with an approach to the solution of the coupled fluid-structure interaction problem, where a viscous incompressible fluid and a rigid body-spring system interact with each other. In order to incorporate the effect of the moving surface of the rigid body, the arbitrary Lagrangian-Eulerian formulation is employed as the basis of the finite element spatial discretization. The semi-coupled numerical method is then used for the time integration of the equations of the motion.