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Wpływ kształtu karbu na rozkłady naprężeń i charakter zniszczenia próbek ze stali S235

Dzioba Ihor, Lipiec Sebastian, Świt Grzegorz, Adamczak-Bugno Anna, Krampikowska Aleksandra

Energetyka

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2023

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nr 11

642--643

PL

W artykule podjęto próbę oceny wpływu kształtu karbu na rozkłady naprężeń oraz charakter zniszczenia próbek ze stali pobranej z infrastruktury gazociągu (stal S235). Analizy oparto na wynikach różnych podejść badawczych: wynikach badań laboratoryjnych z rejestracją sygnałów emisji akustycznej (AE) oraz rezultatów symulacji numerycznych z wykorzystaniem metody elementów skończonych. Pozwoliło to na określenie charakteru rozwoju naprężeń w próbkach wraz z przyłożonym obciążeniem oraz wyznaczenie wartości krytycznych w momencie zniszczenia. Dane te mogą być wykorzystane do definicji kryterium zniszczenia analizowanej stali.

EN

This study attempts to assess the influence of notch shape on the stress distributions and failure character of steel specimens taken from the gas pipeline infrastructure (S235 steel). The analyses were based on the results of different research approaches: the results of laboratory tests with recording of acoustic emission (AE) signals and the results of numerical simulations using the finite element method. This made it possible to determine the nature of the stress development in the specimens with the applied load and to determine the critical values at failure. These data can be used to define the failure criterion of the steel analysed.

2

Thermo-mechanical stress analysis of dissimilar material joints using FEM

Somadder Somnath

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 2

147--153

EN

This article presents numerical investigation of isotropic dissimilar material joints. Dissimilar material joints are broadly used in in various structures, including offshore, nuclear, electronic packaging, IC chip and spacecraft various fields of science and technology. In bi-material joints two different material are bonded with common interface region. High stress concentration occur at the interface of the joint under thermo-mechanical loadings due to the difference in the elastic properties and the thermal expansion coefficients of dissimilar materials.The stresses acting along the interface of dissimilar material joints are very important to determine whether the structure is reliable or not for operation. The main purpose of this research is to provide finite element solutions to predict the stress distribution at the interface of the joint based on the theory of elasticity.

3

Post-critical deformation of thin-walled load-bearing aircraft structure representing fragment of the one-way torsion box

Kopecki Tomasz, Lis Tomasz, Mazurek Przemysław

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 3

203--209

EN

The paper presents results of research on thin-walled load-bearing structure model representing a fragment of plane wing torsion box. The basis for obtaining data on deformation character and stability loss process was a model experiment conducted using a dedicated experimental stand. On the basis of experiment results, adequate numerical simulations were conducted using software based on finite elements method. Results of non-linear numerical analyses allowed to determine the character of stress distribution and formulate conclusions regarding behaviour of the post-critical deformations of the examined wing part.

4

The FEM analysis of stress distribution in front of the crack tip and fracture process in the elements of modified and unmodified cast steel G17CrMo5-5

Pała R., Dzioba I.

Acta Mechanica et Automatica

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2016

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Vol. 10, no. 3

201--206

EN

The article presents influence of modification of the low-alloy cast steel G17CrMo5-5 by rare earth metals on stress distribution in front of the crack at the initial moment of the crack extension. Experimental studies include determination of strength and fracture toughness characteristics for unmodified (UM) and modified (M) cast steel. In the numerical computations, experimentally tested specimens SEN(B) were modelled. The true stress–strain curves for the UM and M cast steel are used in the calculation. The stress distributions in front of the crack were calculated at the initial moment of the crack extension. On the basis of data on the particle size inclusions in the UM and M cast steel, and the calculated stress distributions was performed an assessment of the possibility of the occurrence of cleavage fracture. The analysis results indicate that at room temperature for the UM cast steel, there is a possibility of cleavage fracture, while for the M cast steel occurrence of cleavage fracture is negligible.

5

Wyznaczanie pola temperatury i naprężeń w poziomej komorze przegrzewacza pary na podstawie pomiaru temperatury na powierzchni zewnętrznej

Węglowski B.

Prace Naukowe Politechniki Warszawskiej. Konferencje

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2002

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T. 4, z. 22

1299-1306

PL

Przedstawione zostaną rozkłady temperatury i naprężeń powstające w czasie nagrzewania cylindrycznych elementów kotłów energetycznych. Analizowana będzie pozioma komora wlotowa przegrzewacza pary. Ze względu na to, że "dane pomiarowe", którymi są przebiegi czasowe temperatury na powierzchni zewnętrznej komory są generowane, istnieje możliwość porównania rozkładu temperatury w przekroju poprzecznym otrzymanego z rozwiązania bezpośredniego i odwrotnego.

EN

The transient temperature distribution in the cross-section oh the attemperator header was calculated as the solution of the inverse heat conduction problem with the cross-section divided into the control volumes. The Finite Element Method (FEM) is used to calculate the stresses. The presented example of monitoring transient thermal and strength state on the basis of the temperature measurement on the outer surface shows that thanks to the inverse heat conduction problem solution the developed monitoring way is very accurate.