For the accurate simulation of the rolling process of a wide strip and plates, highly sophisticated algorithms must be developed to couple material flow behavior with the elastic deformation of rolls. A coupling simul...
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For the accurate simulation of the rolling process of a wide strip and plates, highly sophisticated algorithms must be developed to couple material flow behavior with the elastic deformation of rolls. A coupling simulation system based on a three-dimensional rigid-plastic finite element method (RPFEM), elastic-plastic finite element method, and influential function method was developed in this study. Calculation of the continuous variable crown (CVC) mill was more complex than that of the normal 4-high rolling mill. According to the point symmetry of the roll gap profile, the CVC curves of work rolls at various shifting positions were equal to various work roll crowns in normal 4-high mills. Thus, an equivalent model that adopts a 1/4 workpiece for calculation using the RPFEM can be employed to analyze metal deformation. Based on the approximate symmetrical distribution of rolling force, the influential function method was applied to solve the overall elastic deformation of all upper rolls. Thus, reliable results concerning profile transfer and tension distribution were obtained by the coupling the strip model alongside routines for elastic roll stack deflection. The results revealed that the equivalent algorithm can reduce the number of iterations by approximately 50% and the computation time by approximately 80% compared with the traditional algorithm.
Due to a variety of limitations on the system-on-chip (SoC), the microelectronics industry is now facing challenges and making slow progress in recent years. With architecture design and advanced packaging advantages,...
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Due to a variety of limitations on the system-on-chip (SoC), the microelectronics industry is now facing challenges and making slow progress in recent years. With architecture design and advanced packaging advantages, chiplet heterogeneous integration (CHI) systems have become a promising solution to long-lasting hardship. However, high power consumption in CHI systems generates massive heat and makes thermal design a demanding task. Therefore, an accurate tool for thermal simulation is indispensable in the design flow. In this article, a multiscale anisotropic thermal model is proposed for the CHI systems. It considers the feature-scale thermal conductivities of different materials to predict the package-scale steady-state temperature fields. Specifically, the local material composition and thermal conductivity of redistribution layers (RDLs) are extracted from design layout files by constructing an equivalent thermal conductivity algorithm of local feature structures. As for through silicon via (TSV) and bump arrays, the anisotropic distributions of thermal conductivity can also be derived with equivalent algorithms. Other structures are considered homogeneous blocks to significantly reduce the computational expense without losing the generality of the proposed model. Compared with the previous isotropic thermal model of CHI systems, the present multiscale anisotropic thermal model is proven to make temperature prediction and hotspot detection more reliable. With this tool, the reliability problems that are unpredictable and obscure for isotropic thermal models can be identified in advance, and more reasonable design space can be explored in the design flow of the CHI systems.
The mass concrete structures play a very important role in civil engineering. The cracking of concrete is regarded as one of the biggest engineering problems. Therefore, it is very necessary for the cracking of mass c...
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The mass concrete structures play a very important role in civil engineering. The cracking of concrete is regarded as one of the biggest engineering problems. Therefore, it is very necessary for the cracking of mass concrete to do the control analysis. Some factors should be considered in mass concrete crack control analysis, mainly including the heat releases model of concrete, the mechanical model to the concrete, the process of temperature control in the pipe model. Differential evolution algorithm and equivalent algorithm are adopted to solve the coefficient of adiabatic temperature and cool water effect. In the paper, stress field calculation, back analysis calculations, and cooling pipe processing create secondary development based on the ABAQUS software platform. The second development of the code is used to reasonably solve the problem with one actual aqueduct in hydraulic engineering.
An equivalent algorithm is proposed to simulate thermal effects of the magma intrusion in geological systems, which are composed of porous rocks. Based on the physical and mathematical equivalence, the original magma ...
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An equivalent algorithm is proposed to simulate thermal effects of the magma intrusion in geological systems, which are composed of porous rocks. Based on the physical and mathematical equivalence, the original magma solidification problem with a moving boundary between the rock and intruded magma is transformed into a new problem without the moving boundary but with a physically equivalent heat source. From the analysis of an ideal solidification model, the physically equivalent heat source has been determined in this paper. The major advantage in using the proposed equivalent algorithm is that the fixed finite element mesh with a variable integration time step can be employed to simulate the thermal effect of the intruded magma solidification using the conventional finite element method. The related numerical results have demonstrated the correctness and usefulness of the proposed equivalent algorithm for simulating the thermal effect of the intruded magma solidification in geological systems. (C) 2003 Elsevier B.V. All rights reserved.
The solidification of intruded magma in porous rocks can result in the following two consequences: (1) the heat release due to the solidification of the interface between the rock and intruded magma and (2) the mass r...
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The solidification of intruded magma in porous rocks can result in the following two consequences: (1) the heat release due to the solidification of the interface between the rock and intruded magma and (2) the mass release of the volatile fluids in the region where the intruded magma is solidified into the rock. Traditionally, the intruded magma solidification problem is treated as a moving interface (i.e. the solidification interface between the rock and intruded magma) problem to consider these consequences in conventional numerical methods. This paper presents an alternative new approach to simulate thermal and chemical consequences/effects of magma intrusion in geological systems, which are composed of porous rocks. In the proposed new approach and algorithm, the original magma solidification problem with a moving boundary between the rock and intruded magma is transformed into a new problem without the moving boundary but with the proposed mass source and physically equivalent heat source. The major advantage in using the proposed equivalent algorithm is that a fixed mesh of finite elements with a variable integration time-step can be employed to simulate the consequences and effects of the intruded magma solidification using the conventional finite element method. The correctness and usefulness of the proposed equivalent algorithm have been demonstrated by a benchmark magma solidification problem. Copyright (c) 2005 John Wiley & Sons, Ltd.
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