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A three‐dimensional computer simulation of a combustion chamber used in the glass production industry is presented. A numerical solution technique is used to solve the governing time‐averaged partial differential equation and the physical modelling for turbulence, combustion and thermal radiation. A two‐equation turbulence model is employed along with a combustion model based on a fast kinetics statistical approach. A radiation model is used along with the Hottel mixed grey gas model. To solve the governing differential equations an implicit technique of finite‐difference kind is applied. The economy of the computations is very considerably enhanced by the separate calculation of the burner and bulk glass combustion chamber regions, in a manner which takes account of the differing physical nature of their flows. The burner outlet region is calculated with an axisymmetric model. Such two‐dimensional calculations allowed a good resolution of the burner outlet, and provide the inlet conditions for the three‐dimensional calculations of the glass furnace. The prediction procedure is applied to an industrial glass furnace, which operates with oxy‐fuel conditions. Measurements of mean gas temperature and concentrations were performed at different locations in the furnace. The calculated flame length, temperature field and concentrations are with satisfactory agreement with the measured ones.

The purpose of this paper is twofold: first, it aims at the identification and assessment of the commitments towards sustainable development (SD) communicated to all interested parties (stakeholders) by top management; and second, mapping the profile of the organisations which prominently communicate those commitments.

The research methodology was supported on the content analysis of the organisations’ statements (disclosed on the institutional website) that sustain the strategy and policies (organisational culture). A total of 540 certified Portuguese organisations in Quality, Environment and Occupational Health and Safety (QEOHS) comprised the sample.

According to this research, it is possible to identify three main commitments towards SD addressing customers (consumers), human resources (employees) and continuous improvement. Furthermore, results suggest that commitments towards customers and human resources fit properly into the theoretical assumptions of the stakeholder theory and, in turn, the commitment towards continuous improvement fits accurately into the assumptions of the “normative isomorphism” of the institutional theory. Moreover, the results pointed out the characteristics of Portuguese organisations (QEOHS) that prominently communicate commitments towards SD: large business volume, located in Lisbon or Setubal, fall within the public business sector, are members of the BCSD Portugal and publish annual reports on the institutional website.

Solely organisations operating in Portugal and simultaneously encompassing three certified management subsystems (against the clauses of ISO 9001, ISO 14001 and OHSAS 18001 standards) were considered throughout this study. So it is not possible to ascertain at which extent the conclusions are valid. However, although the statistical generalisation of the results may be precluded, there is not any peculiar reason preventing the analytical generalisation, namely, in organisations operating in countries with similar macro-characteristics of Portugal.

To the best of authors’ knowledge this is the first time that such a comprehensive, detailed and thorough analysis of the communicated commitments towards SD is carried out regardless the activity sector. The conclusions from this paper are useful both for practitioners and scholars. On one hand companies have now information on the more often communicated statements, while on the other hand academics and scholars will benefit from this research and hopefully be able to replicate it in other contexts.

This paper seeks to review the literature on methods for solving the radiative transfer equation (RTE) and integrating the radiant energy quantities over the spectrum required to predict the flow, the flame and the thermal structures in chemically reacting and radiating combustion systems.

The focus is on methods that are fast and compatible with the numerical algorithms for solving the transport equations using the computational fluid dynamics techniques. In the methods discussed, the interaction of turbulence and radiation is ignored.

The overview is limited to four methods (differential approximation, discrete ordinates, discrete transfer, and finite volume) for predicting radiative transfer in multidimensional geometries that meet the desired requirements. Greater detail in the radiative transfer model is required to predict the local flame structure and transport quantities than the global (total) radiation heat transfer rate at the walls of the combustion chamber.

The RTE solution methods and integration of radiant energy quantities over the spectrum are assessed for combustion systems containing only the infra‐red radiating gases and gas particle mixtures. For strongly radiating (i.e. highly sooting) and turbulent flows the neglect of turbulence/radiation interaction may not be justified.

Methods of choice for solving the RTE and obtaining total radiant energy quantities for practical combustion devices are discussed.

The paper has identified relevant references that describe methods capable of accounting for radiative transfer to simulate processes arising in combustion systems.

This research aims to analyze the relations between coopetition and innovation, by comparing two coopetitive tourism SMEs networks in Brazil.

The first network comprises 23 SMEs in Honey Island, a natural reserve, and the second network comprises 21 out of 25 SMEs in the Campos Gerais region, recognized by its strong agribusiness. Innovativeness variables included innovation inputs, capabilities, and outputs; and four types of relations that foster innovation were considered, namely, commercial, informational, knowledge, and partnerships. Social network analysis was employed as well as statistical analyses such as Kolmogorov–Smirnov, Mann–Whitney, Spearman correlation and Fischer's Z transformation.

Results show that coopetition is related to SMEs innovativeness. Commercial relations centralities correlated with many innovation outputs, information and knowledge centralities with some innovation inputs and outputs, and partnerships also with capabilities.

Besides contributing to the literature of innovation in tourism, this paper also contributes to the literature on coopetition and innovation by investigating how different types of coopetition relationships foster innovation inputs, capabilities, and outputs.

Managers may benefit from these findings by fostering specific innovation inputs, capabilities, or outputs by means of different coopetition relations. Similarly, regional tourism policy planners may also improve the innovativeness of tourism small businesses by fostering coopetition networks.

This paper not only compares the innovativeness of two small business coopetition networks in the tourism industry but also analyses quantitively in detail how different types of coopetition relations are related to different innovativeness variables.

The purpose is to analyse the nutritional adequacy and carbon footprint of intermediated meals provided to preschool children and primary-level students in a Portuguese municipality.

An observational cross-sectional study was conducted with a convenience sampling consisting of school snacks from a Portuguese municipality. The nutritional assessment used food labels and a Portuguese food composition table. The literature review for carbon footprint assessment was conducted by searching for the products under analysis or similar ones.

The results showed that 80% of snacks have a higher energy value than recommended. The majority of options are below recommendations for protein and fat and above recommendations for carbohydrates. The intermediated meals with more dairy products in composition have the highest carbon footprint. The carbon footprint included the packaging of the products, and it wasn't possible to determine the influence of non-food products.

This study has limitations in the fact that we do not know the carbon footprint of Portuguese products and we had to compare them with others, from different countries, with possibly different types of production.

Intermediate meals are inadequate, and the carbon footprint is higher when the intermediated meals include products of animal origin – the reason why the composition of intermediated meals should be redesigned considering the achievement of these targets.

The promotion of intermediated meals that promote the Mediterranean eating pattern contributes to health and well-being and is a vehicle for nutrition education and healthy food consumption in schools.

Many studies have been conducted to analyse the carbon footprint and environmental impact of school meals, but commonly lunch is the meal evaluated and the assessment of intermediated meals' impact is an open field.

Describes the solution of implicitly discretized fluid flow equations, for turbulent swirling flows, by means of a new iterative method, based on the PISO algorithm. The technique is based on the splitting of the solution process into a series of steps, where, at each step, pressure operations are dissociated from those on velocities. The split sets of equations are solvable by standard numerical techniques. However, in this work, the influence of turbulent quantities and tangential velocity on the momentum equations is taken into account in the splitting process, through the source terms of the discretized equations. Does this by embedding a predictor and a corrector step for the turbulent quantities and for the tangential velocity into the PISO algorithm. This improvement to the standard PISO algorithm leads to a considerable reduction of the computational effort in achieving the same numerically converged solution. Applies the algorithm, in conjunction with a finite‐volume technique, to simulate two different geometries for two‐dimensional (axisymmetric) isothermal turbulent steady‐flows, with and without swirl. Compares the results with predictions of the same flows obtained other iterative methods (SIMPLE) and (PISO). Shows that the algorithm presented herein always exhibits a better efficiency in getting exactly the same final predictions, as far as the number of iterations for convergence and the required central processing unit time are concerned.

This research aims to investigate the influence of the implementation of technical cycles on both captured value and shared value in the circular economy context. Moreover, it analyses the moderating effect of competitive criteria on the relationship between technical cycles and captured value. Finally, it examines the relationship between the captured value and the shared value.

This research follows survey-based research with data gathered from 50 countries and 16 sectors, whose final sample represented 233 organisations. In order to validate the structural and measurement model, the authors applied the partial least squares structural equation modelling technique in the strict rigour of the confirmatory algorithm.

The validated research model demonstrates the value flow through technical cycles. Moreover, it shows the crucial role of the competitive criteria in the value stream through direct, moderate and indirect effects by influencing the relationship between technical cycles and captured and shared values. Finally, the study fills the gap for quantitative studies in the circular economy field.

From a practical perspective, this study contributes to structuring circular business models more robustly, by understanding the influence of competitive criteria (cost, quality, flexibility and delivery) on the conversion of operation strategy in the implementation of the technical cycles in the circular economy context. It contributes to decision-makers, in deciding on which competitive criteria to invest more, which brings more consistent results for technical cycle implementation. It also confirms the importance of partnerships, demonstrating how value cascades from the company through the value network.

As far as is known to date, this is the first study investigating the influence of competitive criteria in the circular economy context. Furthermore, it sheds light on the direct and indirect effects of the technical cycles on value captured by organisations and flow shared value with other players.

This study aims to feature the application of the artificial compressibility method (ACM) for the numerical prediction of two-dimensional (2D) axisymmetric swirling flows.

The respective academic numerical solver, named IGal2D, is based on the axisymmetric Reynolds-averaged Navier–Stokes (RANS) equations, arranged in a pseudo-Cartesian form, enhanced by the addition of the circumferential momentum equation. Discretization of spatial derivative terms within the governing equations is performed via unstructured 2D grid layouts, with a node-centered finite-volume scheme. For the evaluation of inviscid fluxes, the upwind Roe’s approximate Riemann solver is applied, coupled with a higher-order accurate spatial reconstruction, whereas an element-based approach is used for the calculation of gradients required for the viscous ones. Time integration is succeeded through a second-order accurate four-stage Runge-Kutta method, adopting additionally a local time-stepping technique. Further acceleration, in terms of computational time, is achieved by using an agglomeration multigrid scheme, incorporating the full approximation scheme in a V-cycle process, within an efficient edge-based data structure.

A detailed validation of the proposed numerical methodology is performed by encountering both inviscid and viscous (laminar and turbulent) swirling flows with axial symmetry. IGal2D is compared against the commercial software ANSYS fluent – by using appropriate metrics and characteristic flow quantities – but also against experimental measurements, confirming the proposed methodology’s potential to predict such flows in terms of accuracy.

This study provides a robust methodology for the accurate prediction of swirling flows by combining the axisymmetric RANS equations with ACM. In addition, a detailed description of the convective flux Jacobian is provided, filling a respective gap in research literature.

The improvement in the quality of life together with thermal comfort, air quality, health, workplace security and energy conservation measures justify the integral education of environmental (outdoor and/or indoor) phenomena. Environmental education, through the appropriate tool, can play an important and vital role in this domain. Computational fluid dynamics (CFD) is the analysis of systems involving fluid flow, heat transfer and associated phenomena such as distribution of pollutants by means of computer‐based simulation. This technique, allowing the simulation and the visualization of environmental problems, represents a powerful tool to motivate, guide and educate on the environment. The main objective of this paper is to introduce this new advanced active tool in environmental education, directed to indoor‐environment quality, that permits the prediction and visualization of air movement, air temperature and air contaminant (such as tobacco smoke) distribution in rooms. With suitable mathematical models and boundary conditions, a computational code has been developed to predict and visualize these phenomena. In order to demonstrate its applicability, the simulation of air contamination distribution in an office room with a smoker was performed.

Previous research on the impact of coopetition on innovation performance has provided contradictory results. Thus, this study aims to fill the gap by gathering data to explain the impact of coopetition on service innovation, considering the partners’ geographical proximity, innovation focus of the firm and cooperation with customers.

A logistic regression model is applied, and four hypotheses are tested using data from the Eurostat Community Innovation Survey 2018. The cross-sectional data set consists of 13,723 firms innovating services in selected European Union countries.

The findings verify the importance of coopetition for service innovation. However, the coopetitive partners’ nationality does not have a significant impact. Furthermore, the integration of customer cooperation with coopetition enhances service innovation. Hence, competing partners seem not to avoid cooperation in output functions near the customers. To coopete in innovation is risky, but the findings reveal that partners develop novel services through coopetition, intended to produce a higher return to compensate for the risks.

Presumably, this is one of the first large-scale studies examining the impact of coopetition on service innovation in a European context. This study indicates that coopetition amplifies service innovation, thus reducing the divergent views on the impact of coopetition on innovation performance. It responds to the request for more research on the context of coopetitive innovation by explaining how the firms’ geographical proximity, innovation focus and cooperation with customers impact their service innovation performance.