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Article
Publication date: 19 January 2024

Sobhan Pandit, Milan K. Mondal, Dipankar Sanyal, Nirmal K. Manna, Nirmalendu Biswas and Dipak Kumar Mandal

This study aims to undertake a comprehensive examination of heat transfer by convection in porous systems with top and bottom walls insulated and differently heated vertical walls…

Abstract

Purpose

This study aims to undertake a comprehensive examination of heat transfer by convection in porous systems with top and bottom walls insulated and differently heated vertical walls under a magnetic field. For a specific nanofluid, the study aims to bring out the effects of different segmental heating arrangements.

Design/methodology/approach

An existing in-house code based on the finite volume method has provided the numerical solution of the coupled nondimensional transport equations. Following a validation study, different explorations include the variations of Darcy–Rayleigh number (Ram = 10–104), Darcy number (Da = 10–5–10–1) segmented arrangements of heaters of identical total length, porosity index (ε = 0.1–1) and aspect ratio of the cavity (AR = 0.25–2) under Hartmann number (Ha = 10–70) and volume fraction of φ = 0.1% for the nanoparticles. In the analysis, there are major roles of the streamlines, isotherms and heatlines on the vertical mid-plane of the cavity and the profiles of the flow velocity and temperature on the central line of the section.

Findings

The finding of a monotonic rise in the heat transfer rate with an increase in Ram from 10 to 104 has prompted a further comparison of the rate at Ram equal to 104 with the total length of the heaters kept constant in all the cases. With respect to uniform heating of one entire wall, the study reveals a significant advantage of 246% rate enhancement from two equal heater segments placed centrally on opposite walls. This rate has emerged higher by 82% and 249%, respectively, with both the segments placed at the top and one at the bottom and one at the top. An increase in the number of centrally arranged heaters on each wall from one to five has yielded 286% rate enhancement. Changes in the ratio of the cavity height-to-length from 1.0 to 0.2 and 2 cause the rate to decrease by 50% and increase by 21%, respectively.

Research limitations/implications

Further research with additional parameters, geometries and configurations will consolidate the understanding. Experimental validation can complement the numerical simulations presented in this study.

Originality/value

This research contributes to the field by integrating segmented heating, magnetic fields and hybrid nanofluid in a porous flow domain, addressing existing research gaps. The findings provide valuable insights for enhancing thermal performance, and controlling heat transfer locally, and have implications for medical treatments, thermal management systems and related fields. The research opens up new possibilities for precise thermal management and offers directions for future investigations.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 23 January 2024

Md Motiur Rahaman, Nirmalendu Biswas, Apurba Kumar Santra and Nirmal K. Manna

This study aims to delve into the coupled mixed convective heat transport process within a grooved channel cavity using CuO-water nanofluid and an inclined magnetic field. The…

Abstract

Purpose

This study aims to delve into the coupled mixed convective heat transport process within a grooved channel cavity using CuO-water nanofluid and an inclined magnetic field. The cavity undergoes isothermal heating from the bottom, with variations in the positions of heated walls across the grooved channel. The aim is to assess the impact of heater positions on thermal performance and identify the most effective configuration.

Design/methodology/approach

Numerical solutions to the evolved transport equations are obtained using a finite volume method-based indigenous solver. The dimensionless parameters of Reynolds number (1 ≤ Re ≤ 500), Richardson number (0.1 ≤ Ri ≤ 100), Hartmann number (0 ≤ Ha ≤ 70) and magnetic field inclination angle (0° ≤ γ ≤ 180°) are considered. The solved variables generate both local and global variables after discretization using the semi-implicit method for pressure linked equations algorithm on nonuniform grids.

Findings

The study reveals that optimal heat transfer occurs when the heater is positioned at the right corner of the grooved cavity. Heat transfer augmentation ranges from 0.5% to 168.53% for Re = 50 to 300 compared to the bottom-heated case. The magnetic field’s orientation significantly influences the average heat transfer, initially rising and then declining with increasing inclination angle. Overall, this analysis underscores the effectiveness of heater positions in achieving superior thermal performance in a grooved channel cavity.

Research limitations/implications

This concept can be extended to explore enhanced thermal performance under various thermal boundary conditions, considering wall curvature effects, different geometry orientations and the presence of porous structures, either numerically or experimentally.

Practical implications

The findings are applicable across diverse fields, including biomedical systems, heat exchanging devices, electronic cooling systems, food processing, drying processes, crystallization, mixing processes and beyond.

Originality/value

This work provides a novel exploration of CuO-water nanofluid flow in mixed convection within a grooved channel cavity under the influence of an inclined magnetic field. The influence of different heater positions on thermomagnetic convection in such a cavity has not been extensively investigated before, contributing to the originality and value of this research.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Book part
Publication date: 4 March 2024

Oswald A. J. Mascarenhas, Munish Thakur and Payal Kumar

This chapter addresses one of the most crucial areas for critical thinking: the morality of turbulent markets around the world. All of us are overwhelmed by such turbulent…

Abstract

Executive Summary

This chapter addresses one of the most crucial areas for critical thinking: the morality of turbulent markets around the world. All of us are overwhelmed by such turbulent markets. Following Nassim Nicholas Taleb (2004, 2010), we distinguish between nonscalable industries (ordinary professions where income grows linearly, piecemeal or by marginal jumps) and scalable industries (extraordinary risk-prone professions where income grows in a nonlinear fashion, and by exponential jumps and fractures). Nonscalable industries generate tame and predictable markets of goods and services, while scalable industries regularly explode into behemoth virulent markets where rewards are disproportionately large compared to effort, and they are the major causes of turbulent financial markets that rock our world causing ever-widening inequities and inequalities. Part I describes both scalable and nonscalable markets in sufficient detail, including propensity of scalable industries to randomness, and the turbulent markets they create. Part II seeks understanding of moral responsibility of turbulent markets and discusses who should appropriate moral responsibility for turbulent markets and under what conditions. Part III synthesizes various theories of necessary and sufficient conditions for accepting or assigning moral responsibility. We also analyze the necessary and sufficient conditions for attribution of moral responsibility such as rationality, intentionality, autonomy or freedom, causality, accountability, and avoidability of various actors as moral agents or as moral persons. By grouping these conditions, we then derive some useful models for assigning moral responsibility to various entities such as individual executives, corporations, or joint bodies. We discuss the challenges and limitations of such models.

Details

A Primer on Critical Thinking and Business Ethics
Type: Book
ISBN: 978-1-83753-312-1

Article
Publication date: 26 March 2024

Richard John Boulton, Lia Louise Boulton and Michael John Boulton

High levels of interior water vapour lead to condensation and black mould that in turn represent significant risks to residential properties and their occupants. Beliefs about…

Abstract

Purpose

High levels of interior water vapour lead to condensation and black mould that in turn represent significant risks to residential properties and their occupants. Beliefs about window opening are good predictors of the degree to which householders will actually open windows to purge their homes of water vapour, including water vapour that they themselves generate. The present study tested if a short information-giving intervention could enhance householders’ beliefs that foster window opening as purge ventilation and, in turn, lead to greater window opening.

Design/methodology/approach

Data were collected from 242 UK householders with robust psychometrically sound measures embedded in an online self-report survey that also presented the intervention information.

Findings

The intervention led participants, and males in particular, to have significantly greater concerns about condensation and mould and significantly less concerns about heat loss costs arising from opening windows, and these altered beliefs in turn predicted a greater intention to open windows in the future.

Practical implications

By sharing simple information, surveyors and other building professionals can help householders take the simple step of opening their windows and so reduce the threats that condensation and mould present to themselves and their homes.

Originality/value

This is the first study to test (1) a time-based model that predicted the intervention would have a positive effect on specific window opening attitudes and that those new attitudes would in turn affect window opening intentions, and (2) if the intervention had different effects on men and women.

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 1 March 2024

Dale C. Spencer, Rosemary Ricciardelli and Taryn Hepburn

The purpose of this article is to examine the expectations, challenges and tensions officers describe while engaged with public schools to demonstrate that officers engage with…

Abstract

Purpose

The purpose of this article is to examine the expectations, challenges and tensions officers describe while engaged with public schools to demonstrate that officers engage with students in public schools in a conscious, goal-oriented process to establish and maintain useful relationships.

Design/methodology/approach

Data collection involved 104 semi-structured interviews (including follow up interviews) and 31 focus groups, conducted between 2014 and 2018 with police officers working in rural areas of a province in Atlantic Canada.

Findings

Utilizing the concept of social capital, we analyze practices of investments alongside the understanding of rurality as socially interconnected and the rural school as a particular site of interconnectedness for police officers. We demonstrate how, while accumulating social capital, officers face role tension and fundamental barriers when trying to integrate into rural school communities.

Originality/value

By demonstrating the specificities of building social capital in schools and community environments in a rural setting, we contribute to understandings regarding the unique opportunities and challenges faced by police in rural schools in integrating effectively into schools and responding to youth-specific problems.

Details

Policing: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1363-951X

Keywords

Book part
Publication date: 19 March 2024

John Thomas Flynn and Lloyd Levine

A quick search of the headlines of major newspapers reveals a treasure trove of technology procurement gone wrong. While the private sector seems to adopt and implement new…

Abstract

A quick search of the headlines of major newspapers reveals a treasure trove of technology procurement gone wrong. While the private sector seems to adopt and implement new technology seamlessly and quickly to deliver for customers, the government struggles to accomplish technology purchases and integrations with the same ease. As governments in the United States are looking to retain their current workforce and attract the next generation of workers, the technological capabilities and ethos of governments will be paramount. With nearly every industry being transformed by technology and Generation T being the first generation to have an ingrained “technology first” mindset, the ability of governments to attract these workers depends, in large part, on the ability to transform their government technology culture, policies, and practices.

In this chapter, the authors examine the administrative branch and observe two key components at the root of most technology failures: poor organizational structure in the bureaucracy and the lack of an empowered Chief Information/Technology Officer. Building upon case studies from Massachusetts and California, this chapter looks at the factors related to failure or success to understand the technology procurement culture. The chapter concludes by presenting four key “best practice” principles of public policy and administration that can be implemented by almost any governmental entity to improve their acquisition and implementation of technology.

Details

Technology vs. Government: The Irresistible Force Meets the Immovable Object
Type: Book
ISBN: 978-1-83867-951-4

Keywords

Article
Publication date: 28 December 2023

Sandeep Jagani, Xiyue Deng, Paul C. Hong and Narges Mashhadi Nejad

This paper examines the role of a sustainability business model in clarifying a firm's sustainability value articulation (SVA) to achieve sustainability outcomes and examining the…

Abstract

Purpose

This paper examines the role of a sustainability business model in clarifying a firm's sustainability value articulation (SVA) to achieve sustainability outcomes and examining the moderating role of supplier involvement practices SIP and technology systems integration (TSI) in attaining sustainability outcomes.

Design/methodology/approach

Drawing upon the foundational principles of business model innovation, specifically articulation and implementation, the authors formulated a theoretical construct and empirically validate it through analysis of data collected from 692 manufacturing firms dispersed across 23 countries.

Findings

The research shows that focusing on SVA significantly improves how a company implements sustainability efforts internally (ISI) and externally (ESI), leading to better social and environmental outcomes. It also highlights that SIP improve the relationship between SVA, ESI and ISI. Similarly, TSI boosts the effect of internal and external sustainability efforts on both social (SOP) and environmental performance (EnP).

Research limitations/implications

While acknowledging the inherent constraints of survey-based research methodologies, this study offers a theoretical and verified approach for manufacturers to achieve comprehensive sustainability. It emphasizes the need for clear, actionable sustainability goals that can be met through both internal operations and external partnerships.

Practical implications

This study clarifies how manufacturers can implement sustainable business models, emphasizing the importance of clear sustainability goals and initiatives both within and outside the company. It highlights the dual aspects of supplier engagement through operational tactics (ESI) and strategic collaborations (SIP).

Social implications

This study reveals a thrilling truth: when companies champion clear sustainability goals, they unlock powerful strategies that revolutionize practices within their walls and in their external dealings. It is not just about going green; it is about weaving financial prosperity, social responsibility and environmental stewardship into the very fabric of their business models. But there is more – by cleverly engaging suppliers and harnessing cutting-edge technology, companies are not just participants in the green revolution; they are leading it, crafting a world where business thrives alongside the planet and its people.

Originality/value

This research stands out for its empirical analysis of how manufacturing firms implement sustainability innovations at the plant level, an area previously underexplored despite extensive theoretical work on sustainability-centric business models.

Content available
Book part
Publication date: 4 March 2024

Abstract

Details

Managing Destinations
Type: Book
ISBN: 978-1-83797-176-3

Abstract

Details

Teacher Preparation in Papua New Guinea
Type: Book
ISBN: 978-1-83549-077-8

Article
Publication date: 9 January 2024

Fatih Selimefendigil and Hakan F. Oztop

This study aims to examine the effects of cross-flow and multiple jet impingement on conductive panel cooling performance when subjected to uniform magnetic field effects. The…

Abstract

Purpose

This study aims to examine the effects of cross-flow and multiple jet impingement on conductive panel cooling performance when subjected to uniform magnetic field effects. The cooling system has double rotating cylinders.

Design/methodology/approach

Cross-flow ratios (CFR) ranging from 0.1 to 1, magnetic field strength (Ha) ranging from 0 to 50 and cylinder rotation speed (Rew) ranging from −5,000 to 5,000 are the relevant parameters that are included in the numerical analysis. Finite element method is used as solution technique. Radial basis networks are used for the prediction of average Nusselt number (Nu), average surface temperature of the panel and temperature uniformity effects when varying the impacts of cross-flow, magnetic field and rotations of the double cylinder in the cooling channel.

Findings

The effect of CFR on cooling efficiency and temperature uniformity is favorable. By raising the CFR to the highest value under the magnetic field, the average Nu can rise by up to 18.6%, while the temperature drop and temperature difference are obtained as 1.87°C and 3.72°C. Without cylinders, magnetic field improves the cooling performance, while average Nu increases to 4.5% and 8.8% at CR = 0.1 and CR = 1, respectively. When the magnetic field is the strongest with cylinders in channel at CFR = 1, temperature difference (ΔT) is obtained as 2.5 °C. The rotational impacts on thermal performance are more significant when the cross-flow effects are weak (CFR = 0.1) compared to when they are substantial (CFR = 1). Cases without a cylinder have the worst performance for both weak and severe cross-flow effects, whereas using two rotating cylinders increases cooling performance and temperature uniformity for the conductive panel. The average surface temperature lowers by 1.2°C at CFR = 0.1 and 0.5°C at CFR = 1 when the worst and best situations are compared.

Originality/value

The outcomes are relevant in the design and optimization-based studies for electric cooling, photo-voltaic cooling and battery thermal management.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

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