Wyniki wyszukiwania - BazTech

1

Finite element analysis of thermal stress in Cu2O coating synthesized on Cu substrate

Shorinov O.

Archives of Materials Science and Engineering

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2022

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Vol. 115, nr 2

58--65

EN

Purpose: The paper aims to find the magnitude and nature of thermal residual stresses that occur during cooling of a copper sample with a thermally synthesized oxide layer of Cu2O. Design/methodology/approach: Thermo-mechanical analysis was performed by the finite element method using Ansys Software. The results of thermal analysis were used to study the resulting stress-strain state of the thin film/coating system after cooling. Findings: Based on the modeling results, the paper determined the most stress-strain areas of the sample with a coating, which are the free edges of the interfaces between the copper substrate and the Cu2O oxide layer. Research limitations/implications: The main limitations of the study are the use of certain simplifications in the condition setup, for instance, uniform cooling of the thin film/coating system, homogeneity and isotropy of substrate and thin film materials, invariance of their properties with temperature changes, etc. Practical implications: The results obtained can be used to control the stress-strain state of the thin film/coating system and prevent deformations and destruction of thin-film structures during their production and operation of products with them. Originality/value: The study of new promising methods for the formation of oxide nanostructures, for instance in a plasma environment, requires a sufficient theoretical basis in addressing the origin and development of stresses.

2

Modeling of the temperature rises in multiple friction pendulum bearings by means of thermomechanical rheological elements

Bianco Vincenzo, Bernardini Davide, Mollaioli Fabrizio, Monti Giorgio

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 1

171--185

EN

Even if the effectiveness of friction pendulum bearings has been extensively proven by means of numerous experimental programs carried out worldwide, many aspects concerning their behavior under seismic action still need to be clarified. One of these is related to the temperature rises induced by the heat generated by friction during the dynamic sliding of the surfaces in contact, which may significantly affect the superficial frictional properties of the sliding surfaces involved, thus reducing the overall performance of the isolating system, up to re-coupling the structure with the ground shaking, in a limit scenario. With the aim to contribute to a better understanding of this aspect, and to develop a simplified tool capable to reproduce the hysteretic force–displacement loops together with the corresponding temperature variations, a thermo-mechanical model for the multiple friction pendulum devices is proposed. The model is based on the combination of simple thermomechanical rheological elements and does not require the evaluation of any convolution integral arising from the solution of the heat conduction problem as it happens with many existing models. The model is numerically implemented under displacement-control and its effectiveness is validated through the numerical simulation of some recent experimental results that shows a good agreement with the observed behavior.

3

Thermo-mechanical Modelling of the Aircraft Tyre Cornering

Elias-Birembaux L., Rosu I., Lebon F.

Machine Dynamics Research

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2013

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Vol. 37, No. 1

29-36

EN

Some numerical models are proposed for simulate the aircraft tyre behaviour on the ground in critical situations. Fully coupled thermo-mechanical analysis procedures taking into account finite deformation, dynamics and frictional contact are studied. The proposed tuodels are compared with experimental data such as contact area, lateral and longitudinal stiffnesses, surface temperature evolution due to friction, self-alignment torque, and lateral "Friction coefficients. A good agreement is observed at low speed (less than 70 km/h). Thus, the model is extrapolated to high speeds and seems able to predict results in cases for which it is not possible to obtain realistic experimental data.

4

Higher-order FEM for analysis of coupled problems

Kansy R., Cecot W.

Czasopismo Techniczne. Budownictwo

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2013

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R. 110, z. 2-B

29--39

EN

The paper presents the application of the hp-adaptive FEM to numerical analysis of coupled problems. HP3D code is especially discussed, as well as some topics concerning mesh adaptation and numerical aspects of modeling coupled problems on the example of weakly coupled thermo-mechanical problem. Some possibilities of the new code are illustrated by a numerical example motivated by a real engineering problem. Finally, some future possible and desirable directions of development for this code are noted.

PL

W artykule przedstawiono zastosowanie hp-adaptacyjnej MES do analizy numerycznej problemów sprzężonych. W szczególności omówiono program HP3D i pewne wątki dotyczące adaptacji siatki oraz numerycznych aspektów modelowania problemów sprzężonych. Niektóre możliwości nowego programu ilustruje przykład numeryczny motywowany rzeczywistym inżynieryjnym problemem. Wskazano również na możliwe i pożądane przyszłe kierunki rozwoju tego oprogramowania.

5

Thermo-mechanical phenomena in the process of friction welding of corundum ceramics and aluminium

Lindemann Z., Skalski K., Włosiński W., Zimmerman J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2006

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Vol. 54, nr 1

1-8

EN

In the paper the modelling of thermo-mechanical effects in the process of friction welding of corundum ceramics and aluminium is presented. The modelling is performed by means of finite element method. The corundum ceramics contains 97% of AhO3. The mechanical and temperature fields are considered as coupled fields. Simulation of loading of the elements bonded with the beat flux from friction beat on the contact surface is also shown The beat flux was modified in the consecutive time increments of numerical solutions by changeable pressure on contact surface. Time depending temperature distribution in the bonded elements is also determined. The temperature distribution on the periphery of the cylindrical surfaces of the ceramics and Al was compared to the temperature measurements done with a thermovision camera. The results of the simulation were compared to those obtained from the tests performed by means of a friction welding machine.