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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 purpose of this paper is to introduce a novel computational method to evaluate damage accumulation in a solder joint of an electronic package, when exposed to operating temperature environment. A procedure to implement the method is suggested, and a discussion of the method and its possible applications is provided in the paper.

Methodologically, interpolated response surfaces based on specially designed finite element (FE) simulation runs, are employed to compute a damage metric at regular time intervals of an operating temperature profile. The developed method has been evaluated on a finite-element model of a lead-free PBGA256 package, and accumulated creep strain energy density has been chosen as damage metric.

The method has proven to be two orders of magnitude more computationally efficient compared to FE simulation. A general agreement within 3 percent has been found between the results predicted with the new method, and FE simulations when tested on a number of temperature profiles from an avionic application. The solder joint temperature ranges between +25 and +75°C.

The method can be implemented as part of reliability assessment of electronic packages in the design phase.

The method enables increased accuracy in thermal fatigue life prediction of solder joints. Combined with other failure mechanisms, it may contribute to the accuracy of reliability assessment of electronic packages.

Describes the development of a static‐explicit type finite‐element formulation based on non‐linear elastic plastic shells, non‐linear contact friction and Barlat anisotropic plasticity with modified corner theory. Newly introduces the spin of the anisotropic axes as a means of deriving the objective stress rate. Demonstrates that a C⁰ continuous shell is an efficient finite element for large‐scale computation. Uses membrane shell theory to derive a kinematic description of the external contact force. Offers an explanation of the ways in which the material, press load and lubrication affect the deformation and strain localization in the automotive sheet metal forming process. Demonstrates a trial of virtual manufacturing incorporating finite‐element simulation, a visualized inspection system and a heuristic process optimization scheme.

During the current global epidemic, e-learning and mobile learning have been rapidly developed in the field of entrepreneurship education. The effect of these learning methods remains to be confirmed. The purpose of this paper is to explore the effect of mobile business simulation games in entrepreneurship education.

From May 2020 to July 2020, the authors adopted a quasi-experimental design to explore the effect of mobile business simulation games in entrepreneurship education. The authors set up an experimental group to participate in mobile business simulation games, with a total of 105 students, and set up a control group of 100 students. At the beginning and end of the experiment, data on entrepreneurial attitude, self-efficacy, entrepreneurial intention and other related variables were collected. Paired sample T-test and regression analysis were used to analyze the results.

The authors found that mobile business simulation games can improve entrepreneurial attitudes and self-efficacy, but cannot change entrepreneurial intentions. The paired sample T-test in the experimental group showed that the entrepreneurial attitude and entrepreneurial self-efficacy of the participants were significantly improved, but the entrepreneurial intention did not change significantly. The above three variables did not change significantly in the control group. The research results also show that flow experience is very important in mobile business simulation games, which can improve entrepreneurial attitude and entrepreneurial self-efficacy.

The authors’ findings confirm the positive effects of mobile business simulation games in entrepreneurship education, which can improve entrepreneurial attitudes and entrepreneurial self-efficacy. But the disadvantage of mobile business simulation games is that they cannot increase entrepreneurial intention. In addition, the flow experience needs to be valued in mobile business simulation games. The research in this paper has implications for how mobile learning can be used in entrepreneurship education during the COVID-19 pandemic. In addition, research is of great value on how mobile business simulation games can be improved.

To provide a new method for the determination of motor characteristics by means of FE‐methods suitable for multi‐variable design processes.

The process is based on two‐dimensional, steady state and frequency domain FE‐analysis including a stepwise movement of the rotor. The process consists of the following steps: generation of an appropriate FE‐model with specific mesh generation; input of the machines parameters and the parameters of the simulation process; no load simulation: cogging torque T, no load fluxes ψ_mo and voltages u_o and the phase angles of the windings currents; load simulation with given currents: average and the pulsating torque T, fluxes ψ_l(α), voltages U, two‐axis model parameters ψ_m, L_d and L_q; determination of operating characteristics: torque T, voltage U, current I, power P, angles β and δ cos ϕ, as functions of speed n. Based on machine parameters from step 3 and 4 determination of losses in the magnets by means of a frequency domain model and the fluxes in the magnet from steps 3 and 4.

Special attention has to be given to the mesh design. The mesh configuration should be kept constant during the movement. Motor parameters are determined for one operating point. The process is very fast and accurate enough ( < errors) for design purposes.

It is shown how FE‐methods can be used in motor design, avoiding time‐consuming transient simulations.

It is a new and very efficient FE‐process for motor design.

The purpose of this paper is to present a study of radial aircraft tire for safety assessment during various scenarios.

A detailed finite element (FE) model of aircraft tire was established based on the actual geometry of the target tire for numerical simulations. As the major component of this tire, rubber material usually presents a complicated mechanical behavior. To obtain the reliable hyperelastic properties of rubber, a series of material tests have been processed. Moreover, in order to validate the proposed model, the simulations results of inflation and static load scenarios were compared with the experimental results. Both of the control volume and corpuscular particle method methods were used in the numerical simulations of aircraft tire.

The comparisons of the two methods exhibit close agreement with the experimental results. To assess the safety of aircraft tire during the landing scenario, the dynamic simulations were processed with different landing weights and vertical landing speeds. According to the relevant airworthiness regulations and technical documents, the tire pressure, deflection and load have been chosen as the safety criteria. Subsequently, the analysis, results and comments have been discussed in detail.

The validated FE model proposed in present study can be effectively used in tire modeling in static and dynamic problems, and also in the design process of aircraft tire.

Induction machines for traction applications are operated at working points of high ferromagnetic saturation. Depending on the working point, a broad spectrum of harmonic frequencies appears in the magnetic flux density of induction machines. Detailed loss analysis therefore requires local and temporal highly resolved nonlinear field computation. This loss analysis can be performed in the post processing of nonlinear transient finite element simulations of the magnetic circuit. However, it takes a large number of transient simulation time steps to build up the rotor flux of the machine.

In this paper, hybrid simulation approaches that couple static FEA, transient FEA and analytic formulations to significantly decrease the number of simulation time steps to calculate the magnetic field in steady state are discussed, analyzed and compared.

The proposed hybrid simulation approaches drastically decrease the simulation time by shortening the transient build-up of the rotor flux. Depending on the maximum error of the rotor flux linkage amplitude compared to the steady state value, a reduction of simulation time steps in the range of 55.5 to 98 per cent is found.

The presented hybrid simulation approaches allow efficient performing of the transient FE magnetic field simulations of induction machines operated as traction drives.

This paper aims to present 3D finite element (FE) simulations of impact loading on a construction safety helmet over a headform to improve the ventilation slots profile in helmet design.

Impact response on headforms in three different studies considering ventilation slots of varied profiles and dimensions in helmets with rectangular elliptical and circular slots is compared and analysed. Head injury criteria (HIC) and safety regulations from past literature have been considered to evaluate the impact responses.

Simulation results show that a helmet with rectangular ventilation slots achieves a lowest peak impact force of 5941.3 N for a slot area of 170 mm² as compared to elliptical and circular slots.

Ventilation slots of simple geometry (rectangular, elliptical and circular) have been considered in this work. Other/complex geometry slots can also be chosen to predict its effect during impact response on a helmet–headform model. Biofidelic head–neck FE model can be developed to achieve precise results.

The presented work gives a clear idea to design engineers for the selection of ventilation slot profiles to design a construction safety helmet.

Construction safety (CS) helmets are used to reduce injuries on heads of workers at construction sites in the event of free-falling objects. Rectangular ventilation slots in CS helmets as suggested in the work may reduce the risk of injury.

Results are found in good agreement with the past numerical simulation of impact response on a construction safety helmet over a validated biofidelic head FE model.

To propose an air‐gap element for electrical machine simulation which accounts for static and dynamic rotor eccentricity.

The air‐gap element technique is extended to account for a non‐centered rotor. The consistency, stability and convergence of the discretisation error are studied. A specialized efficient solution technique combining the conjugate gradient algorithm with fast Fourier transforms is developed.

The eccentric air‐gap technique offers better discretisation properties than the classical techniques based on remeshing. Thanks to the specialized solver, the computation times remain comparable.

The introduction of eccentricity in the air‐gap element used for finite element electrical machine simulation is a new development.

There are structural elements on the aircraft that may be exposed to high-intensity sound levels. One of them is an air inlet duct of the jet engine. To prepare data for the air duct damage tolerance analysis, flat panels were tested under acoustic loading. The paper aims to discuss this issue.

The acoustic fatigue test equipment for grazing wave’s incidence was designed based on the FE analyses. Flat composite panels were designed and manufactured using the Hexply 8552/AGP193-PW prepreg with the simulation of production imperfections or operational damage. The dynamic behaviour of panels has been tested using three regimes of acoustic loading: white noise spectrum, engine noise spectrum and discrete harmonic frequencies. The panel deflection was monitored along its longitudinal axis, and the ultrasonic NDT instruments were used for the monitoring of relevant delamination increments. The FE model of the panel was created in Abaqus to study panel dynamic characteristics.

No delamination progress was observed by NDT testing even if dynamic characteristics, especially modal frequency, of the panel changed during the fatigue test. Rayleigh damping coefficients were evaluated for their use in FE models. Significant differences were found between the measured and computed panel deflection curves near the edge of the panel.

The research results underscored the signification of the FE model boundary conditions and the element type selections when the panel works like a membrane rather than a plate because of their low bending stiffness.