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A complete thermo‐mechanical model for the simulation of the inertia welding process of two similar parts is described. The material behaviour is represented by an incompressible viscoplastic Norton—Hoff law in which the rheological parameters are dependent on temperature. The friction law was determined experimentally and depends on the prescribed pressure and the relative rotating velocity between the two parts. The mechanical problem is solved considering the virtual work principle including inertia terms. The computation of the three components of the velocity field such as radial, longitudinal and rotational velocity, in an axisymmetric approximation allows to take into account the torsional effects. The domain is updated based on a Lagrangian formulation. The non‐linear heat transfer equation with boundary conditions (convection, radiation and friction flux) is solved separately for each time step. Error estimators on mechanical and thermal computation are devised to adapt the mesh in an automatic way. Finally, numerical results concerning evolution of parts shape, strain, temperature, rotating velocity, upsetting are compared with actual industrial welds.

Focuses on the inverse problems arising from the simulation of forming processes. Considers two sets of problems: parameter identification and shape optimization. Both are solved using an optimization method for the minimization of a suitable objective function. The convergence and convergence rate of the method depend on the accuracy of the derivatives of this function. The sensitivity analysis is based on a discrete approach, e.g. the differentiation of the discrete problem equations. Describes the method for non‐linear, non‐steady‐state‐forming problems involving contact evolution. First, it is applied to the parameter identification and to the torsion test. It shows good convergence properties and proves to be very efficient for the identification of the material behaviour. Then, it is applied to the tool shape optimization in forging for a two‐step process. A few iterations of the inverse method make it possible to suggest a suitable shape for the preforming tools.

A numerical model for solving either elastic‐plastic, elastic‐viscoplastic or purely viscoplastic deformation of thin sheets is presented, using a membrane mechanical approach. The finite element method is used associated with an incremental procedure. The mechanical equations are the principle of virtual work written in terms of plane stress, which is solved at the end of each increment, and an incremental semi‐implicit flow rule obtained by the time integration of the constitutive equations over the increment. These equations are written using curvilinear coordinates, and membrane elements are used to discretize them. The resolution method is the Newton‐Raphson algorithm. The contact algorithm is presented and allows for applications to cold stretching and deep‐drawing problems and to the superplastic forming of thin sheets.

The purpose of this paper is to present an immersed volume method that accounts for solid conductive bodies (hat‐shaped disk) in calculation of time‐dependent, three‐dimensional, conjugate heat transfer and fluid flow.

The incompressible Navier‐Stokes equations and the heat transfer equations are discretized using a stabilized finite element method. The interface of the immersed disk is defined and rendered by the zero isovalues of a level set function. This signed distance function allows turning different thermal properties of each component into homogeneous parameters and it is coupled to a direct anisotropic mesh adaptation process enhancing the interface representation. A monolithic approach is used to solve a single set of equations for both fluid and solid with different thermal properties.

In the proposed immersion technique, only a single grid for both air and solid is considered, thus, only one equation with different thermal properties is solved. The sharp discontinuity of the material properties was captured by an anisotropic refined solid‐fluid interface. The robustness of the method to compute the flow and heat transfer with large materials properties differences is demonstrated using stabilized finite element formulations. Results are assessed by comparing the predictions with the experimental data.

The proposed method demonstrates the capability of the model to simulate an unsteady three‐dimensional heat transfer flow of natural convection, conduction and radiation in a cubic enclosure with the presence of a conduction body. A previous knowledge of the heat transfer coefficients between the disk and the fluid is no longer required. The heat exchange at the interface is solved and dealt with naturally.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

The effect of bending is investigated through the comparison of the membrane analysis and the shell analysis for stretching and deep drawing. An incremental formulation incorporating the effect of shape change and anisotropy is used for the analysis of elastic‐plastic non‐steady large deformation. The deformation during a step is considered using the natural convected coordinate system. Stretching of a square blank with a hemispherical punch and deep drawing of a cyclindrical cup is analysed and the corresponding experiments are carried out. The computational results are compared with the experiments. In stretching, the comparison has shown that both the membrane analysis and the shell analysis are in good agreement with the experiment for punch load and strain distribution. In deep drawing, the computed loads of both the membrane analysis and the shell analysis are generally in good agreement with the experiment. The computed thickness strain of the membrane analysis, however, shows a wide difference with the experiment. In the shell analysis, the thickness strain shows good agreement with the experiment. It has been shown that the membrane approach shows a limitation for the deep drawing process in which the effect of bending is not negligible and more exact informations on the thickness strain distribution are required.

Addresses the computational aspects involved in the numerical simulation of sheet stamping processes. Focuses on some numerical aspects of the intrinsic complexity of these problems, the first of which is the necessity to take into account properly membrane and bending effects. Presents a well‐adapted shell element. The second aspect concerns the description and the implementation of the initial orthotropic plastic behaviour for sheet metal parts, based on a formulation in a rotating frame using the initial microstructure rotation. The stress calculation algorithm is based on a particular implementation of the elastic predictor‐plastic corrector method. The last aspect concerns the solution procedures with a particular development concerning the treatment of the blankholder load as a constraint. A set of computational results validated with experiments prove the accuracy of the proposed approach in solving stamping problems.

The premise of this research is that the coupling of reinforcement learning algorithms and computational dynamics can be used to design efficient control strategies and to improve the cooling of hot components by quenching, a process that is classically carried out based on professional experience and trial-error methods. Feasibility and relevance are assessed on various 2-D numerical experiments involving boiling problems simulated by a phase change model. The purpose of this study is then to integrate reinforcement learning with boiling modeling involving phase change to optimize the cooling process during quenching.

The proposed approach couples two state-of-the-art in-house models: a single-step proximal policy optimization (PPO) deep reinforcement learning (DRL) algorithm (for data-driven selection of control parameters) and an in-house stabilized finite elements environment combining variational multi-scale (VMS) modeling of the governing equations, immerse volume method and multi-component anisotropic mesh adaptation (to compute the numerical reward used by the DRL agent to learn), that simulates boiling after a phase change model formulated after pseudo-compressible Navier–Stokes and heat equations.

Relevance of the proposed methodology is illustrated by controlling natural convection in a closed cavity with aspect ratio 4:1, for which DRL alleviates the flow-induced enhancement of heat transfer by approximately 20%. Regarding quenching applications, the DRL algorithm finds optimal insertion angles that adequately homogenize the temperature distribution in both simple and complex 2-D workpiece geometries, and improve over simpler trial-and-error strategies classically used in the quenching industry.

To the best of the authors’ knowledge, this constitutes the first attempt to achieve DRL-based control of complex heat and mass transfer processes involving boiling. The obtained results have important implications for the quenching cooling flows widely used to achieve the desired microstructure and material properties of steel, and for which differential cooling in various zones of the quenched component will yield irregular residual stresses that can affect the serviceability of critical machinery in sensitive industries.

The purpose of this paper is to integrate branding and higher education literature to conceptualize, develop, and empirically examine a model of university social augmenters’ brand equity.

Drawing on an empirical survey of 401 undergraduate students enrolled in private universities in Egypt, this study model was tested using structural equation modeling.

The findings reveal that university social augmenters’ reputation, coach-to-student interactions, and student-to-student interactions influence students’ satisfaction with social augmenters. The results also suggest that students satisfied with university social augmenters are more likely to exhibit outcomes of brand equity – namely, brand identification, willingness to recommend, and willingness to incur an additional premium cost.

The results offer managerial implications for university administrators in their quest to enrich students’ university experiences and build strong sub-brands within the university setting. University social augmenters are found to have strong brand equity manifestations and may hold the potential to differentiate university brands in an industry dominated by experience and credence.

This research contributes to the extant literature by filling two gaps in university branding literature. First, previous research has never unified separate streams of literature related to augmented services and brand equity. Second, limited conceptual and empirical research on university branding in general and university social augmentation in particular has been conducted in emerging markets, which has resulted in conceptual ambiguity for the key factors constructing students’ university social experiences.

Student engagement is a multifaceted concept that directly impacts students and their education. The purpose of this paper is to discuss student engagement conceptually by offering a framework to better understand the deliverables of engagement in the form of generic and targeted outcomes.

The design of the study is based on a detailed literature review, to identify different types of engagement which graduates are expected to experience during their higher education studies. These types of engagement(s) are mapped with their outcomes.

The findings of this study would be an analysis of relevant studies to create an outcome-oriented conceptual framework for student engagement.

The practical implications of the study would be to provide a guide for enhancing student engagement through which both generic competencies and higher order competencies of students may be augmented.

The available literature suggests that many students lack focus when learning on campus, especially in meeting targeted outcomes, and do not engage in the community. The current study has incorporated generic and targeted outcomes expected as a result of the different types of engagement. The study has put forward certain propositions, suggesting new dimensions of research in the domain of student engagement.