M. Taha Janan and A. El Marjani
This paper aims to develop an efficient numerical method for simulating multicomponent flows by solving the system of conservative equations closed by a general two parameters…
Abstract
Purpose
This paper aims to develop an efficient numerical method for simulating multicomponent flows by solving the system of conservative equations closed by a general two parameters equation of state.
Design/methodology/approach
A finite difference method for solving the two‐dimensional Euler or Navier‐Stokes equations for multicomponent flows in a general curvilinear coordinate system is developed. The system of conservative equations (mass, momentum and energy) is closed with a general two parameters equation of state (ρe=(p+γp∞)/(γ−1)), which, associated to a γ‐formulation, allows easy computation of multicomponent flows. In order to enforce the stability of the numerical scheme, the Roe's flux‐difference splitting is adopted for the numerical treatment of the inviscid fluxes. The method is adapted to treat also unsteady flows by implementing an explicit Euler scheme.
Findings
The method was applied to compute various configurations of flows, ranging from incompressible to compressible fluid, including cases of single component flows or multicomponent ones. Computations show that the use of primitive variables instead of conservative ones, especially at low Mach numbers, improves the iteration process when the resolution is performed with a relaxation procedure such as Gauss‐Seidel method. Simulations of compressible flows with a strong shock show the ability of the present method to capture shocks correctly even with the use of primitive variables. To complete numerical tests, flows involving two fluids with the presence of interactions between a shock and a discontinuity surface have been treated successfully. Also, a case of cavitating flow has been considered in this work.
Originality/value
The present method permits the simulation of a large variety of multicomponent complexes flows with an efficient numerical taking advantage of Roe's flux‐difference splitting in curvilinear coordinate system.
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Teresa Parra-Santos, J.R. Pérez-Domínguez, R.Z. Szasz and F. Castro-Ruiz
One current trend in burner technology is to obtain high efficiency while keeping low levels of NOx emissions. A swirling flow in combustion ensures a fixed position of a compact…
Abstract
Purpose
One current trend in burner technology is to obtain high efficiency while keeping low levels of NOx emissions. A swirling flow in combustion ensures a fixed position of a compact flame. Therefore, it is necessary to design efficient swirlers. Flow patterns are simulated for the different swirl devices proposed in this work. Two axial-swirlers are studied: one based on curve-vanes consisting of a straight line with an arc of a circle as the trailing edge and the other is the common flat-vanes. The purpose of this paper is to assess the accuracy of different swirl generators using a well-known benchmark test case.
Design/methodology/approach
This work deals with modelling the swirler using two approaches: the general purpose Computational fluid dynamics (CFD) solver Ansys-Fluent® and the suite of libraries OpenFOAM® to solve the Reynolds Averaged Navier Stokes equations, showing there is a slight deviation between both approaches. Their performance involves analyzing not only the Swirl number but also the size of the recirculation zones in the test chamber. A subsequent process on the flow patterns was carried out to establish the intensity of segregation which provides insight into the quality of mixing.
Findings
CFD models are feasible tools to predict flow features. It was found that numerical results tend to reduce the inner recirculation zone (IRZ) radial size. Further, an increase of the swirl number involves larger IRZ and a smaller outer recirculation zone (ORZ). The curved swirler displays a better axi-symmetric behaviour than flat vanes. There is weak influence of the chord vanes on the swirl number. The number of vanes is a compromise of head loses and guidance of the flow.
Originality/value
The paper offers two different approaches to solve turbulent swirling flows. One based in a general contrasted commercial tool and other using open source code. Both models show similar performance. An innovative set up for an axial swirler different from the conventional flat vanes was proposed.
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Ahmed Khadhraoui and Cherif Adnen
The purpose of this study is to present a new approach of a hydrogen-based green energy supply system intended for powering electric vehicles using fuel cells (FCs) and suitable…
Abstract
Purpose
The purpose of this study is to present a new approach of a hydrogen-based green energy supply system intended for powering electric vehicles using fuel cells (FCs) and suitable for sustainable urban automobile transportations.
Design/methodology/approach
To resolve the problems with current electric vehicles, which are cost, autonomy and charging infrastructure, the authors have developed in this study a new prototype which uses an autonomous hydrogen production system, embedded in the vehicle and assisted by a photovoltaic source and ion-lithium batteries. The on-board produced hydrogen is then used by a reversible FC (PEMFC) to generate electricity to power the vehicle engine.
Findings
The obtained results demonstrated that the FC could provide approximately 70% of the required current once the vehicle was in motion, with the remaining 30% supplied by the battery. The carbon dioxide (CO2) emissions were reduced of 98%.
Research limitations/implications
A most vehicles use an internal combustion engine causing serious air pollution and the inability to meet new clean energy standards with zero CO2 emissions. In this same context, hybrid vehicles produce at least 80 g of CO2 every km, which is much higher than the Kyoto, Copenhagen and Paris COP21 policies.
Social implications
This study will help to create the best ecological ecosystem with low greenhouse emissions.
Originality/value
This concept offers many advantages, such as increased range, reduced recharge time, increasing the system autonomy and no CO2 emissions, which contribute to reducing air pollution, regulation with CE protocols and moving toward cleaner and more sustainable mobility.
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Matti Haverila, Kai Christian Haverila and Caitlin McLaughlin
Against the backdrop of dynamic capabilities theory, this research examines the relationship between knowledge and marketing agility in the context of big data marketing analytics…
Abstract
Purpose
Against the backdrop of dynamic capabilities theory, this research examines the relationship between knowledge and marketing agility in the context of big data marketing analytics (BDMA). The relevant knowledge constructs under investigation are business/marketing, relational, technological and technology management. The level of BDMA deployment is also examined to determine its impact on these relationships.
Design/methodology/approach
A survey was used to gather data from marketing professionals working in firms with at least limited experience in big data (BD) deployment in the United States and Canada. The results were analyzed using partial least squares structural equation modeling (PLS-SEM) with a sample of 236 responses.
Findings
The results indicate that marketing professionals perceived the knowledge and marketing agility constructs differently than the previous research on IT professionals. The knowledge construct was perceived as a two-dimensional construct consisting of broad knowledge skills and specific technical knowledge skills. Only the broad knowledge skills construct was significantly related to the marketing agility construct, with progressively high predictive validity and relevance when the deployment of BDMA progresses.
Originality/value
The paper's originality stems from the different conceptualizations of the knowledge and marketing agility constructs due to the use of a novel sample of marketing professionals in this study. The research also contributes to the dynamic capabilities theory by emphasizing the critical role of vital knowledge when aiming to enhance marketing agility.
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Tayfun Yıldız, Betül Balkan Akan, Ünsal Sığrı and Marina Dabić
Tacit and explicit knowledge sharing play crucial roles in today’s rapidly changing business environment, particularly in fostering innovation. However, uncovering tacit knowledge…
Abstract
Purpose
Tacit and explicit knowledge sharing play crucial roles in today’s rapidly changing business environment, particularly in fostering innovation. However, uncovering tacit knowledge sharing remains complex. The purpose of this study is to analyze the mediating roles of tacit and explicit knowledge in the relationship between a knowledge-sharing culture and organizational creativity.
Design/methodology/approach
In this study, the authors developed an extended analytical process to analyze the impact of explicit and tacit knowledge on a knowledge-sharing culture and organizational creativity. This process combines two analytical techniques: necessary condition analysis (NCA) and partial least squares structural equation modeling (PLS-SEM). NCA identifies essential bottlenecks for a specific outcome, while PLS-SEM uncovers strong connections between predictor and outcome variables. The authors applied these analyses to a sample of 155 IT experts from a leading telecom company in the Turkish ICT industry to test the relevant hypotheses.
Findings
The findings of this study indicate that tacit knowledge, rather than explicit knowledge, partially mediates the relationship between a knowledge-sharing culture and organizational creativity. This mediating role of tacit knowledge is particularly pronounced in the ICT sector. Additionally, the impact of organizational capabilities on organizational creativity is amplified by higher levels of tacit knowledge sharing.
Originality/value
The effect of organizational capabilities on organizational creativity was found to increase because of tacit knowledge sharing compared to explicit knowledge sharing, depending on the knowledge-sharing climate.
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Hossein Omrany, Amirhosein Ghaffarianhoseini, Ali Ghaffarianhoseini and Derek John Clements-Croome
This paper critically analysed 195 articles with the objectives of providing a clear understanding of the current City Information Modelling (CIM) implementations, identifying the…
Abstract
Purpose
This paper critically analysed 195 articles with the objectives of providing a clear understanding of the current City Information Modelling (CIM) implementations, identifying the main challenges hampering the uptake of CIM and providing recommendations for the future development of CIM.
Design/methodology/approach
This paper adopts the PRISMA method in order to perform the systematic literature review.
Findings
The results identified nine domains of CIM implementation including (1) natural disaster management, (2) urban building energy modelling, (3) urban facility management, (4) urban infrastructure management, (5) land administration systems, (6) improvement of urban microclimates, (7) development of digital twin and smart cities, (8) improvement of social engagement and (9) urban landscaping design. Further, eight challenges were identified that hinder the widespread employment of CIM including (1) reluctance towards CIM application, (2) data quality, (3) computing resources and storage inefficiency, (4) data integration between BIM and GIS and interoperability, (5) establishing a standardised workflow for CIM implementation, (6) synergy between all parties involved, (7) cybersecurity and intellectual property and (8) data management.
Originality/value
This is the first paper of its kind that provides a holistic understanding of the current implementation of CIM. The outcomes will benefit multiple target groups. First, urban planners and designers will be supplied with a status-quo understanding of CIM implementations. Second, this research introduces possibilities of CIM deployment for the governance of cities; hence the outcomes can be useful for policymakers. Lastly, the scientific community can use the findings of this study as a reference point to gain a comprehensive understanding of the field and contribute to the future development of CIM.
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Sha Zhang, Zhengqi Gu, Wenguang Wu, Ledian Zheng, Jun Liu and Shanbin Yin
The purpose of this paper is to develop a numerical model used for calculating the nonlinearities of large-scale hydro-pneumatic suspension (HPS) and investigating the effects of…
Abstract
Purpose
The purpose of this paper is to develop a numerical model used for calculating the nonlinearities of large-scale hydro-pneumatic suspension (HPS) and investigating the effects of variations in flow path and operational parameter on suspension damping response.
Design/methodology/approach
To parameterization nonlinearities of the suspension, the author developed a two-phase flow model of a large-scale HPS based on computational fluid dynamics and volume of fluid method. Considerable effort was made to verify the nonlinearities by field measurements carried out on an off-highway mining dump truck. The investigation of effects of variations in flow path and operational parameter on damping characteristics highlights the necessity of the numerical simulation.
Findings
The two-phase flow model can represent the gas-oil interaction and simulate the suspension operational movement conveniently. Transient numerical simulation results can be used to model the nonlinearities of large-scale HPS accurately. A new phenomenon was discovered that the pressure in rebound chamber presents reduction trend during compression stroke in special cases. It has never been reported before.
Originality/value
Developed a two-phase flow model of a large-scale HPS, which can manage the gas-oil interaction and capture the complex flow field structure in it. The paper is the first study to model the nonlinearities of a large-scale HPS used in off-highway mining dump truck through transient numerical simulation. Compared with previous researches, such a research not only gives new insight and thorough understanding into the suspension internal fluid structure but also can give good guiding opinions to the optimal design of HPS.
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Deden Sumirat Hidayat, Dana Indra Sensuse, Damayanti Elisabeth and Lintang Matahari Hasani
Study on knowledge-based systems for scientific publications is growing very broadly. However, most of these studies do not explicitly discuss the knowledge management (KM…
Abstract
Purpose
Study on knowledge-based systems for scientific publications is growing very broadly. However, most of these studies do not explicitly discuss the knowledge management (KM) component as knowledge management system (KMS) implementation. This background causes academic institutions to face challenges in developing KMS to support scholarly publication cycle (SPC). Therefore, this study aims to develop a new KMS conceptual model, Identify critical components and provide research gap opportunities for future KM studies on SPC.
Design/methodology/approach
This study used a systematic literature review (SLR) method with the procedure from Kitchenham et al. Then, the SLR results are compiled into a conceptual model design based on a framework on KM foundations and KM solutions. Finally, the model design was validated through interviews with related field experts.
Findings
The KMS for SPC focuses on the discovery, sharing and application of knowledge. The majority of KMS use recommendation systems technology with content-based filtering and collaborative filtering personalization approaches. The characteristics data used in KMS for SPC are structured and unstructured. Metadata and article abstracts are considered sufficiently representative of the entire article content to be used as a search tool and can provide recommendations. The KMS model for SPC has layers of KM infrastructure, processes, systems, strategies, outputs and outcomes.
Research limitations/implications
This study has limitations in discussing tacit knowledge. In contrast, tacit knowledge for SPC is essential for scientific publication performance. The tacit knowledge includes experience in searching, writing, submitting, publishing and disseminating scientific publications. Tacit knowledge plays a vital role in the development of knowledge sharing system (KSS) and KCS. Therefore, KSS and KCS for SPC are still very challenging to be researched in the future. KMS opportunities that might be developed further are lessons learned databases and interactive forums that capture tacit knowledge about SPC. Future work potential could identify other types of KMS in academia and focus more on SPC.
Originality/value
This study proposes a novel comprehensive KMS model to support scientific publication performance. This model has a critical path as a KMS implementation solution for SPC. This model proposes and recommends appropriate components for SPC requirements (KM processes, technology, methods/techniques and data). This study also proposes novel research gaps as KMS research opportunities for SPC in the future.
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Iñaki Periáñez-Cañadillas, Jon Charterina and Julián Pando-García
The purpose of this paper is to examine the role of digital competences in relation to the general competences demanded by the job market in the case of Business graduates’ future.
Abstract
Purpose
The purpose of this paper is to examine the role of digital competences in relation to the general competences demanded by the job market in the case of Business graduates’ future.
Design/methodology/approach
A telephone survey was conducted with 992 team and HR managers from November 15 to December 15, 2016. The selected respondents were chosen from a sampling frame of 4,880 registered members of a professional association of Business and Economics graduates. Only those admitting to have or having had employees under their command were accountable. Thus, the final sample of the analysis comprised a total of 231 respondents. We used partial least square modeling in order to test the hypotheses.
Findings
The study carried out in the professional field of graduates in Business studies shows us that of the five dimensions analyzed as digital competences, four of them show an influence on the candidate’s suitability for the post. These are communication, content creation, safety and problem solving. In the variables related to information, this relationship is not observed.
Originality/value
In this research, the authors analyze the digital competences from the perspective of the possible employer. The concept of digital competence is of increasing importance in recent research. There is a need to relate the competences demanded by the companies and those developed by the training centers. Also, prior literature is limited in the number of works analyzing digital competences specifically in the professional activities concerning graduates in Economics of Business studies.