K. Rama Narasimha, S.N. Sridhara, M.S. Rajagopal and K.N. Seetharamu
The purpose of this paper is to present a numerical investigation on pulsating heat pipe (PHP) to study the slug velocities as a function of various parameters.
Abstract
Purpose
The purpose of this paper is to present a numerical investigation on pulsating heat pipe (PHP) to study the slug velocities as a function of various parameters.
Design/methodology/approach
The governing equation of PHP is solved using explicit embedded Runge‐Kutta method, the Dormand–Prince pair in conjunction with MATLAB with the nomenclature 45 for the determination of displacement and the velocity of the slug.
Findings
The results show that lower fill ratio, higher diameter, higher operating temperature and higher temperature difference between evaporator and condenser for a given working fluid results in higher slug velocities, indicating higher momentum transfer and hence better heat transport.
Research limitations/implications
Under steady state conditions, the design of a PHP is facilitated through the introduction of non‐dimensional numbers.
Originality/value
The displacement and slug velocities for additional working fluids, namely ethanol and methanol, are determined for the first time. The behaviour of non‐dimensional numbers, i.e. Poiseuille number, capillary number and Eckert number in a PHP as a function of various parameters have been studied for the first time.
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S. Hoseinzadeh, S.M. Taheri Otaghsara, M.H. Zakeri Khatir and P.S. Heyns
The purpose of this study is to investigate the pulsating flow in a three-dimensional channel. Channel flow is laminar and turbulent. After validation, the effect of different…
Abstract
Purpose
The purpose of this study is to investigate the pulsating flow in a three-dimensional channel. Channel flow is laminar and turbulent. After validation, the effect of different channel cross-sectional geometries (circular, hexagonal and triangular) with the pulsating flow are investigated. For this purpose, the alumina nanofluid was considered as a working fluid with different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent).
Design/methodology/approach
In this study, the pulsatile flow was investigated in a three-dimensional channel. Channel flow is laminar and turbulent.
Findings
The results show that the fluid temperature decreases by increasing the volume percentage of particles of Al2O3; this is because of the fact that the input energy through the wall boundary is a constant value and indicates that with increasing the volume percentage, the fluid can save more energy at a constant temperature. And by adding Al2O3 nanofluid, thermal performance improves in channels, but it should be considered that the use of nanofluid causes a pressure drop in the channel.
Originality/value
Alumina/water nanofluid with the pulsating flow was investigated and compared in three different cross-sectional channel geometries (circular, hexagonal and triangular). The effect of different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent) of Al2O3 nanofluid on temperature, velocity and pressure are studied.
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Amir Rezazad Bari, Mohammad Zabetian Targhi and Mohammad Mahdi Heyhat
This study aims to examine the effect of a combination of hybrid pin-fin patterns on a heat sink's performance using numerical techniques. Also, flow characteristics have been…
Abstract
Purpose
This study aims to examine the effect of a combination of hybrid pin-fin patterns on a heat sink's performance using numerical techniques. Also, flow characteristics have been studied, such as secondary flow formation and flow-wall interaction.
Design/methodology/approach
In this study, the effect of hybrid arrangements of elliptical and hexagonal pin-fins with different distribution percentages on flow characteristics and performance evaluation criteria in laminar flow was investigated. Ansys-Fluent software solves the governing equations using the finite volume method. Also, the accuracy of obtained results was compared with the experimental results of other similar papers.
Findings
The results of this study highlighted that hybrid arrangements show higher overall performance than single pin-fin patterns. Among the hybrid arrangements, case 3 has the highest values of performance evaluation criteria, that is, 1.84 in Re = 900. The results revealed that, with the instantaneous change in the pattern from elliptic to hexagonal, the secondary flow increases in the cross-sectional area of the channels, and the maximum velocity in the cross-section of the channel increases. The important advantages of case 3 are its highest overall performance and a lower chip surface temperature of up to about 2% than other hybrid patterns.
Originality/value
Prior research has shown that in the single pin-fin pattern, the cooling power at the end of the heat sink decreases with increasing fluid temperature. Also, a review of previous studies showed that existing papers had not investigated hybrid pin-fin patterns by considering the effect of changing distribution percentages on overall performance, which is the aim of this paper.
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Narasimha Murthy, Kuldip Singh Sangwan and Nuggenahalli S. Narahari
The purpose of this paper is to examine how sub-criteria of the European Foundation for Quality Management (EFQM) model is structurally connected and influence each other. This…
Abstract
Purpose
The purpose of this paper is to examine how sub-criteria of the European Foundation for Quality Management (EFQM) model is structurally connected and influence each other. This paper also tries to find the underpinning logics in the EFQM model.
Design/methodology/approach
The study uses the empirical methodology based on assessment scores of 58 different organizations to gauge the underlying structure, develop the construct and establish interlinkages among the various sub-criteria in the EFQM model. Statistical analysis is used to find the impact on results and cross influencing of criteria at the sub-criteria level. The factorial analysis is carried out using the Doe technique to create factorial plots for result categories (customer results, people results, society results and business results). The approach is to unravel (1) the role played by each sub-criterion of the model, (2) the effects of sub-criteria on the results of the EFQM model and (3) the influence of sub-criteria on the managerial aspects of the model in an organizational context.
Findings
The EFQM sub-criteria are categorised as promoters, proponents, defenders or detractors based on their impact on the results and cross-influence on each other. The study unfolded seven sub-criteria positively impacting the results and one sub-criterion negatively impacting the results if not handled properly. Out of 32 sub-criteria, nine sub-criteria are influencing more than six other sub-criteria.
Originality/value
The paper investigates, for the first time: (1) the role played by each sub-criteria of the model; (2) the relationships that are produced between these sub-criteria on the EFQM results and (3) identify how such sub-criteria would influence the managerial aspects of the model in an organizational context. This research develops underlying logics in the EFQM model using Doe factorial methods for overcoming the multi-collinearity.
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Vidya Rao, Rama Devi Nandineni and Shaji Kananchira Panicker
This study aims to read ritual performances, built forms and cultural undertones of traumatic migration in the settlements of people at the periphery of mainstream history at…
Abstract
Purpose
This study aims to read ritual performances, built forms and cultural undertones of traumatic migration in the settlements of people at the periphery of mainstream history at Mattancherry in Kochi, India. Interactions between their culture, faith, location, ethnicity and community enterprise are explored. This study is essential in the context of negative social perceptions of internal migration and migrants.
Design/methodology/approach
The methodology is ethnography and includes interdisciplinary fieldwork of transect walks, participant observations, unstructured interviews and architectural documentation. Secondary references were community publications and scholarly journals.
Findings
Constant resilient rebuilding was possible through shared identity and community enterprise. Community temples, monastic institutions, volunteer groups and emerging high-net-worth individuals contributed to nurturing this identity. The temple rituals encouraged an egalitarian outlook. Throughout the settlement’s existence, the centrality of the temple and its religious activities remained constant. Community cohesion and endogamous practices create a cultural island distinct from the general population. Community enterprise also meant contribution to prosperity as productive citizens in the region and beyond.
Originality/value
Religion and shared history-based ethnic community enterprise for survival and prosperity postmigration are observed in this settlement. The conducive entrepreneurial atmosphere is set in its historical, cultural and religious context. This study can, therefore, provide insights for policymakers and academia about the interactions between culture, faith and history during the entrepreneurial process. The cultural context is explored as a backdrop of community enterprise posttraumatic migration, informing societal perceptions about migration and migrants.
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Mersiha Tepic, Frances Fortuin, Ron G.M. Kemp and Onno Omta
The aim of this paper is to establish the differences between the food and beverages (F&B) and technology-based industries with regards to the relation between previously…
Abstract
Purpose
The aim of this paper is to establish the differences between the food and beverages (F&B) and technology-based industries with regards to the relation between previously identified success factors and innovation project performance.
Design/methodology/approach
These differences are established on the basis of logistic regression analysis, using 38 innovation projects (18 F&B and 20 technology-based).
Findings
Newness of the innovation project to the company, communication capabilities and market potential have a more negative impact on innovation project performance in the F&B than the tech-based industry. Especially functional upstream capabilities increase the likelihood of success in F&B, when compared to tech-based innovation projects.
Practical implications
While functional upstream capabilities are important for success of F&B innovation projects, there is still room for improvement in order to deal effectively with newness of the innovation project to the company. Internalization of resources from the network and a balanced radical/incremental innovation project portfolio contribute to additional enhancement of functional capabilities of the F&B companies, improving their capacity to deal with newness. Through a larger focus on co-innovation with retail, F&B companies can improve their intra- and inter-firm communication capabilities to attain more consumer-oriented integration of R&D and marketing activities, improving the market potential of their innovations.
Originality/value
This paper demonstrates that the previously identified critical success factors for innovation projects differ in impact and importance for F&B innovation project performance when compared to innovation projects in the technology-based industry.
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Sumit K. Majumdar and Arnab Bhattacharjee
Literature, spanning industrial organization and strategic management disciplines, uses variance decomposition to understand the relative importance of firm, industry and business…
Abstract
Purpose
Literature, spanning industrial organization and strategic management disciplines, uses variance decomposition to understand the relative importance of firm, industry and business group effects in shaping profitability variations. Some literature analyzes firm profitability under transition to liberalization. Previous research has taken a static before-and-after view on institutional change. This paper aims to focus on the dynamic process of liberalization in India, analyzing how different institutional regime changes alter firm behavior leading to changes in profitability patterns.
Design/methodology/approach
Based on a panel data set of several thousand Indian firms, spanning the 26-year period between 1980-1981 and 2005-2006, the authors determine the relative importance of firm, industry and business group effects in explaining manufacturing firms’ profitability variances across different institutional phases. The authors evaluate three propositions that help assess transition dynamics between phases. They determine the quantum of catch-up or falling behind by firms.
Findings
Different industries emerge as profitability leaders, as the economy progresses through different liberalization phases. Business groups that have been more effective in resource appropriation, rent-seeking, politician management and non-market activities in a controlled regime are replaced as profit leaders by those that, in a free-market economy, can be capable of intra-business resource allocation tasks and leveraging corporate capabilities.
Originality/value
The approach demonstrates how to analyze the underlying detailed structure of firm-level data, and performance outcomes, to derive nuanced interpretation of factors giving rise to the effects that explain profitability variances, and how to assess the way these effects behave over time. The dynamic evidence-based approach highlights what factors matter, where, when and why, in influencing profitability variances, which are a key dimension of industrial and economic performance.
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This study aims to explain the state-of-the-art machine learning models that are used in the intrusion detection problem for human-being understandable and study the relationship…
Abstract
Purpose
This study aims to explain the state-of-the-art machine learning models that are used in the intrusion detection problem for human-being understandable and study the relationship between the explainability and the performance of the models.
Design/methodology/approach
The authors study a recent intrusion data set collected from real-world scenarios and use state-of-the-art machine learning algorithms to detect the intrusion. The authors apply several novel techniques to explain the models, then evaluate manually the explanation. The authors then compare the performance of model post- and prior-explainability-based feature selection.
Findings
The authors confirm our hypothesis above and claim that by forcing the explainability, the model becomes more robust, requires less computational power but achieves a better predictive performance.
Originality/value
The authors draw our conclusions based on their own research and experimental works.