Papers by Keyword: Thermo-Mechanical Coupling

Abstract: When a material is subjected to a cyclic loading at high values of stress or strain, both thermal and damage develop together with cyclic plastic strain. These processes are often accompanied by damage deactivation characterized by actual state of micro-cracks, which are generally active under tension and passive under compression. In classical formulation damage deactivation occurs instantly when loading changes sign and consequently leads to non-smooth path separating both load ranges. The real materials, however, do not exhibit such bilinear paths. Therefore, the more realistic model based on continuous damage deactivation is proposed, in which micro-cracks close gradually, see Cegielski and Ganczarski [2, 3, 4], Hansen and Schreyer [5]. Simultaneously, thermo-mechanical coupling may play essential role in processes of cyclic plasticity hence present formulation comprises an additional heat transfer equation.

Abstract: A finite element model is developed to study the transient thermo-mechanical contact between a rough body and a flat body. The model consideres the heat flux coupling, the interaction among adjacent contact asperities and elasto-plastic deformation of the rough body. It is observed that the temperature / contact pressure / stress are coupled and fluctuate obviously when the interaction of contact asperities enhances. The fluctuation of the VonMises equivalent stress makes the equivalent plastic strain of the frictional surface layer accumulate continually which might cause fatigue wear and plastic deformation wear of the material when the frictional rotating process repeated.

Abstract: The numerical simulation of the cross-rolling stainless steel/carbon steel double metal composite seamless steel tube process was conducted through the finite element analysis of the three-dimensional thermo-mechanical coupled elastic-plastic by applying the MSC.MARC software. Based on the numerical simulation, The character of stress, strain and temperature distribution parameters during the two roll cross-rolling were obtained by the finite element analysis, and acquired the section pass deformation figure. The distribution of the axial stress, circle stress and radial stress were drawn in the cross-rolling roll gap profile along the circle. The mechanism of tube cross-rolling process was explained according to the stress distribution. The results of the research can be applied to the design of the cross-rolling forming process.

Abstract: Used the finite element method, the rolling process analysis mod Analysis el of 3500mm rolling mill is established in this paper based on the thermal mechanical analysis theory, according to the rolling technology parameters in actual production, the rolling process of plate rolling is systematic analyzed, which thinks about the thermal stress caused by uneven temperature distribution. The law of technology parameters influencing rolling process is gained, which uses in the optimization of rolling process, improves production efficiency. it has important significance to reduce the energy consumption.

Abstract: For the tubular C/C-weaving composite is often loaded on thermotics and mechanics loads together in using, adopting the sequential coupling method, utilizing the finite element analysis software: firstly analyze the stress distribution on loading temperature and pressure loads together, the maximums and changing rules of displacement, stress and strain have been obtained. Based on the works above, further to analyze the thermo-mechanical coupling of different loads, the curves of displacement, stress and strain in the specified paths have been obtained, it shows that the influence from temperature on every parameters is little when loading on the larger loads. So come to the conclusion that the tubular C/C composite has good temperature stability and can be used in the condition of high temperature or temperature changes greatly.

Abstract: The automatic weapons suffered the coupling load of in-bore pressure and temperature load during firing, which exerted a serious influence on the gun barrel life. Suppose the gun barrel was thick wall cylinders, the relations among the radial stress, tangential stress, longitudinal stress and equivalent stress in thick wall cylinders enduring interior pressure and temperature loads were analyzed by traditional analytic method, 2D finite element method (FEM) and 3D FEM respectively. Boundary effects of the stress field in thick wall cylinders were also analyzed. The obtained results showed that 3D FEM is suitable for the analysis on boundary effects, and the coupling stress could be designed and optimized by adjusting the interior pressure or temperature loads.

Abstract: Heat generation and deformation of bearing are key factors that influence the rigidity and machining accuracy of the high-speed precision spindle system. Based on heat transfer and thermodynamics, the finite element model of angular contact ball bearing is established for thermal deformation. The contact stress and thermal deformation are analyzed and obtained at a speed of . The results show that the maximum contact stress and thermal deflection appeared at contact region, which is in accordance with actual status. The results provide the reference and the theory basis for research into thermal deformation of bearing.

Abstract: In this paper a three-dimensional tubular braided carbon/carbon composite model is presented, the calculated formula of the fiber volume fraction is deduced and the related performance parameters are calculated. Comparisons of displacements and stresses for the thermo-mechanical coupling are analyzed. The simulation results can help designers to analyze material property.

Abstract: The thermo-mechanical coupling finite element models of disc brakes made of aluminum metal matrix composites and cast iron for a passenger car under different emergency braking conditions were deveoped. And the braking process for brake disc was simulated by using finite element method. By analyzing distributions of the temperature field and stress field of the two brake discs with different thickness under emergency braking conditions, the weight reduction of the brake discs by using aluminum metal matrix composites substrate for cast irons was discussed and the simulation resusts showed that brake discs made of aluminum metal matrix composties can be used for passenger cars.

Abstract: t is required to use specialized large-scale pressure cooker to process and cook rice in high altitude. The design of large-scale pressure cooker with composite bottom is a very complicated process, involving in nominal operating pressure, safe pressure and breakdown pressure, etc., especially the advantage of composite-bottom pressure cooker possesses, which are fast heat conduction, high efficiency and energy conservation, but it is very easy to ignore thermo-mechanical coupling effect which the compound aluminum steel of pressure cooker with composite bottom exerted in the hot operation working condition in the process of designing pressure cooker, once the bottom is dropped due to the condition of high temperature, the whole feeding equipment will not work properly. Analysis software ANSYS is applied to make simulating calculation for thermo-mechanical coupling of super-huge type pressure cooker with composite bottom, verifying if it can operate properly in the field condition of long time and high temperature.