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The purpose of the paper is to predict the aerodynamic performance of a complete scale model H-Darrieus vertical axis wind turbine (VAWT) with end plates at different operating conditions. This paper aims at understanding the flow physics around a model VAWT for three different tip speed ratios corresponding to three different flow regimes.

This study achieves a first three-dimensional hybrid lattice Boltzmann method/very large eddy simulation (LBM-VLES) model for a complete scaled model VAWT with end plates and mast using the solver PowerFLOW. The power curve predicted from the numerical simulations is compared with the experimental data collected at Erlangen University. This study highlights the complexity of the turbulent flow features that are seen at three different operational regimes of the turbine using instantaneous flow structures, mean velocity, pressure iso-contours, blade loading and skin friction plots.

The power curve predicted using the LBM-VLES approach and setup provides a good overall match with the experimental power curve, with the peak and drop after the operational point being captured. Variable turbulent flow structures are seen over the azimuthal revolution that depends on the tip speed ratio (TSR). Significant dynamic stall structures are seen in the upwind phase and at the end of the downwind phase of rotation in the deep stall regime. Strong blade wake interactions and turbulent flow structures are seen inside the rotor at higher TSRs.

The computational cost and time for such high-fidelity simulations using the LBM-VLES remains expensive. Each simulation requires around a week using supercomputing facilities. Further studies need to be performed to improve analytical VAWT models using inputs/calibration from high fidelity simulation databases. As a future work, the impact of turbulent and nonuniform inflow conditions that are more representative of a typical urban environment also needs to be investigated.

The LBM methodology is shown to be a reliable approach for VAWT power prediction. Dynamic stall and blade wake interactions reduce the aerodynamic performance of a VAWT. An ideal operation close to the peak of the power curve should be favored based on the local wind resource, as this point exhibits a smoother variation of forces improving operational performance. The 3D flow features also exhibit a significant wake asymmetry that could impact the optimal layout of VAWT clusters to increase their power density. The present work also highlights the importance of 3D simulations of the complete model including the support structures such as end plates and mast.

Accurate predictions of power performance for Darrieus VAWTs could help in better siting of wind turbines thus improving return of investment and reducing levelized cost of energy. It could promote the development of onsite electricity generation, especially for industrial sites/urban areas and renew interest for VAWT wind farms.

A first high-fidelity simulation of a complete VAWT with end plates and supporting structures has been performed using the LBM approach and compared with experimental data. The 3D flow physics has been analyzed at different operating regimes of the turbine. These physical insights and prediction capabilities of this approach could be useful for commercial VAWT manufacturers.

This article aims to evaluate the current state and planned progress of lesson study (LS) in Switzerland, specifically focusing on the efforts made by different university teacher education institutions across three language regions of the country.

First, a literature review is carried out to establish the LS research situation in Switzerland. In a second step, LS projects implemented in three different language regions across Switzerland and key findings thereof will be presented.

LS in Switzerland has progressed in terms of research, as can be seen from the publication of 18 papers from seven different universities and classified into three categories. The majority of these papers stem from the Lausanne Laboratory Lesson Study. Swiss LS has also attracted attention in some neighbouring countries. Nevertheless, the sustainability of the LS process in Switzerland is still in its infancy. Some unfavourable factors are due to the cantonal and versatile structure of the Swiss education system. However, thanks to the centre of expertise for LS at Lausanne University of Teacher Education, LS is expanding to other regions of Switzerland.

While this paper does not delve into extensive research on the development of LS in Switzerland, it highlights the need for further research to analyse the conditions and constraints impacting the sustainability of learning communities in the country.

This paper represents the first literature review specifically addressing LS in Switzerland, offering a comprehensive assessment of its research development. Additionally, it is the first study to examine the development of learning communities across different language regions of the country. Moreover, it shows how LS can be implemented and adapted to the varied educational preconditions in Switzerland.

The purpose of this study is to analyse the impact of two determinants of purchase intention in food label campaigns: altruistic attribution and brand equity.

A 2 × 2 between-group factorial experimental design was used, with 2 levels of altruistic attribution (high/low) and 2 levels of brand equity (high/low). The product used for the study was pork chops. A survey was conducted on 602 respondents representing the population of Quebec, Canada.

Structural equation modelling was used to evaluate the fit of the data with the proposed mod el. The results demonstrate that altruistic attribution and brand equity have an indirect impact on purchase intention via perceptions of taste and food safety. Altruistic attribution, but not brand equity, also has a direct impact on purchase intention.

The experiment in this study was conducted via an online consumer panel to increase internal validity. As a result, one of the limitations of the study concerns its external validity.

This research provides strategic guidelines for businesses or organisations that wish to develop food label campaigns. They must simultaneously consider both altruistic attribution and pre-existing brand equity.

This study contributes to the literature by demonstrating the impact of altruistic attribution and brand equity on purchase intention in the context of food label campaigns. The study mobilises attribution theory and the multidimensional consumer-based brand equity scale.

The purpose of this paper is to use different model order reduction techniques to cope with the computational effort of solving large systems of equations. By appropriate decomposition of the electromagnetic field problem, the number of degrees of freedom (DOF) can be efficiently reduced. In this contribution, the Proper Generalized Decomposition (PGD) and the Proper Orthogonal Decomposition (POD) are used in the frame of the T-Ω-formulation, and the feasibility is elaborated.

The POD and the PGD are two methods to reduce the model order. Particularly in the context of eddy current problems, conventional time-stepping algorithms can lead to many numerical simulations of the studied problem. To simulate the transient field, the T-Ω-formulation is used which couples the magnetic scalar potential and the electric vector potential. In this paper, both methods are studied on an academic example of an induction furnace in terms of accuracy and computational effort.

Using the proposed reduction techniques significantly reduces the DOF and subsequently the computational effort. Further, the feasibility of the combination of both methods with the T-Ω-formulation is given, and a fundamental step toward fast simulation of eddy current problems is shown.

In this paper, the PGD is combined for the first time with the T-Ω-formulation. The application of the PGD and POD and the following comparison illustrate the great potential of these techniques in combination with the T-Ω-formulation in context of eddy current problems.

To take account of the uncertainties introduced on the magnetic properties during the manufacturing process, the present work aims to focus on the stochastic modelling of iron losses in electrical machine stators.

The investigated samples are composed of 28 slinky stators, coming from the same production chain. The stochastic modelling approach is first described. Thereafter, the Monte‐Carlo sampling method is used to calculate, in post‐processing, the iron loss density in a PMSM that is modelled by the finite element method.

The interest of such an approach is emphasized by calculating the main statistical characteristics associated to the losses variability, which are Gaussian distributed for A and Ω formulations.

The originality of the approach is due to the fact that the global influence of the manufacturing process (cutting, assembly, …) on magnetic properties of the considered samples is taken into account in the way of computing the iron losses.

This paper aims to deal with the verification of local quantities of interest obtained through linear elastic finite element analysis. A technique is presented for determining the most accurate error estimation. This technique enables one to address industrial‐size problems while keeping computing costs reasonable.

The concept of error in constitutive relation is used to assess the quality of the finite element solution. The key issue is the construction of admissible fields. The objective is to show that it is possible to build admissible fields using a new method. These fields are obtained by using a high‐quality construction over a limited zone while the construction is less refined and less expensive elsewhere.

Numerical tests are presented in order to illustrate a very satisfying presented methodology. It shows clearly how to take advantage of the method to treat large examples. They clearly show the interest of this new method to treat large examples.

The paper demonstrates clearly that verification of large finite element problem must have dedicated methods in order to be applicable.