Wyniki wyszukiwania - BazTech

1

Application of metric entropy for results interpretation of composite materials mechanical tests

Garbacz G., Kyzioł L.

Advances in Materials Science

|

2017

|

Vol. 17, nr 1(51)

70--81

EN

In this paper the results of mechanical studies of the Aropol 536 composite on the epoxy-resin base are described. The aim of the studies was to measure elastic-plastic changes in the composite during its deformation. The obtained results were analyzed using Kolmogorov-Sinai metric entropy. The entropy was computed applying phase portraits reconstructed from a phase plane using delayed coordinates. Resolution of the particular experimental setup limits the number of the acquired data points, i.e., from several to tens of thousands of points and it has significant influence on accuracy of the obtained results. In conclusion, in the tested composites elastic-plastic deformations are periodic and repeat in a distinctive way in a wide range of deformations of the sample. Deformation of the elastic-plastic composite are associated with its complex structure and studies of its mechanical properties require more advanced methods such as use of Kolmogorov-Sinai metric entropy.

2

Influence of mesh refinement on results of elastic-plastic FEM analysis

Szabracki P., Lipiński T.

Technical Sciences / University of Warmia and Mazury in Olsztyn

|

2014

|

nr 17(2)

149--163

EN

To improve fitting of numerical results to experimental data, in the past, distances between nodes were decreased for whole mesh. A typical mesh generator for Finite Element Method (FEM) analysis ensures possibility to decrease distances between nodes for edges or surfaces of described geometries. Influence of local mesh refinement for a flat and round tensile specimen on fitting of numerical tensile simulation results to experimental data was presented in the paper. Local mesh refinement was performed for areas with the error values higher than threshold value. First iteration of flat and round mesh refinement has to improved correlation of numerical and experimental data with acceptable increase of mesh file size. Similar observations have been made for the second iteration of the flat specimen mesh. On the basis of analysis, shown that second iteration of round mesh refinement caused crucial increase of mesh file size and computation time with negligible fitting improvement.

3

Odkształcenia sprężysto-plastyczne elipsoidalnych den naczyń ciśnieniowych

Magnucki K., Szyc W.

Archiwum Technologii Maszyn i Automatyzacji

|

1999

|

Vol. 19, Nr 1

77-86

PL

Przedmiotem analizy są dna wypukłe w kształcie elipsoidy obrotowej cienkościennych zbiorników ciśnieniowych. Ciśnienie zewnętrzne, a także wewnętrzne może powodować utratę stateczności dna. W wielu praktycznych rozwiązaniach zjawisko to zachodzi w zakresie sprężysto-plastycznym. W artykule przedstawiono wyniki analizy numerycznej zrealizowanej z użyciem metody elementów skończonych. Rezultaty obliczeń wskazują na zbieżność z opisanymi w literaturze odkształceniami zachodzącymi w rzeczywistych konstrukcjach.

EN

The ellipsoidal domed heads of thin-walled pressure vessels are the object of the analysis. External, and also internal pressure may cause the stability loss of such heads. In many real technical cases this phenomenon takes place in elastic-plastic range. In the paper the results of numerical analysis realized with the help of the finite element method are presented. They give indication of conformity between obtained effects and deformations occuring in real structures.