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Multiple encapsulated phase change materials (PCMs) are used in a wide range of applications, including convective drying, electronic cooling, waste heat recovery and air conditioning. Therefore, it is important to understand the performance of multiple PCMs in channels with flow separation and develop methods to increase their effectiveness. The aim of the study is to analyze the phase transition dynamics of multiple encapsulated PCMs mounted in a U-shaped tube under inclined magnetic field by using ternary nanofluid.

The PCMs used in the upper horizontal channel, vertical channel and lower horizontal channel are denoted by M1, M2 and M3. Magnetic field is uniform and inclined while finite element method is used as the solution technique. Triple encapsulated-PCM system study is carried out taking into account different values of Reynolds number (Re, ranges from 300 to 1,000), Hartmann number (Ha ranges from 0 and 60), magnetic field inclination (between 0 and 90) and solid volume fraction of ternary nanofluid (between 0 and 0.03). The dynamic response of the liquid fraction is estimated for each PCM with varying Re, Ha and t using an artificial neural network.

It is observed that for PCMs M2 and M3, the influence of Re on the phase transition is more effective. For M2 and M3, entire transition time (t-F) lowers by approximately 47% and 47.5% when Re is increased to its maximum value, whereas it only falls by 10% for M1. The dynamic characteristics of the phase transition are impacted by imposing MGF and varying its strength and inclination. When Ha is raised from Ha = 0 to Ha = 50, the t-F for PCM-M2 (PCM-M3) falls (increases) by around 30% (29%). For PCMs M1, M2 and M3, the phase transition process accelerates by around 20%, 30% and 28% when the solid volume fraction is increased to its maximum value.

Outcomes of this research is useful for understanding the phase change behavior of multiple PCMs in separated flow and using various methods such as nano-enhanced magnetic field to improve their effectiveness. Research outputs are beneficial for initial design and optimization of using multiple PCMs in diverse energy system technologies, including solar power, waste heat recovery, air conditioning, thermal management and drying.

This paper aims to study the effect of concentric hot circular cylinder inside egg-cavity porous-copper nanofluid on natural convection phenomena.

The finite element method–based Galerkin approach is applied to solve numerically the set of governing equations with appropriate boundary conditions.

The effects of different range parameters, such as Darcy number (10–3 = Da = 10–1), Rayleigh number (103 = Ra = 106), nanoparticle volume fraction (0 = ϑ = 0.06) and eccentricity (−0.3 = e = 0.1) on the fluid flow represent by stream function and heat transfer represent by temperature distribution, local and average Nusselt numbers.

A comparison between oval shape and concentric circular concentric cylinder was investigated.

In the current numerical study, heat transfer by natural convection was identified inside the new design of egg-shaped cavity as a result of the presence of a circular inside it supported by a porous medium filled with a nanofluid. After reviewing previous studies and considering the importance of heat transfer by free convection inside tubes for many applications, to the best of the authors’ knowledge, the current work is the first study that deals with a study and comparison between the common shape (concentric circular tubes) and the new shape (egg-shaped cavity).

The purpose of this study is to advance turbulent thermal convection inside the constant heat-flux round tube inserted by multiple perforated twisted tapes.

The novel design of this study is accomplished by inserting several twisted tapes and drilling some circular perforations near the tape edge (C1, C3, C5: solid tapes; C2, C4, C6: perforated tapes). The turbulence flow appearances and thermal convective features are examined for various Reynolds numbers (8,000–14,000) using the renormalization group (RNG) κ−ε turbulent model and Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm.

The simulated outcomes reveal that inserting more perforated-twisted tapes into the heated round tube promotes turbulent thermal convection effectively. A swirling flow caused by the twisted tapes to produce the secondary flow jets between two reverse-spin tapes can combine with the main flow passing through the perforations at the outer edge to enhance the vortex flow. The primary factors are the quantity of twisted tapes and with/without perforations, as the perforation ratio remains at 2.5 in this numerical work. Weighing friction along the tube, C6 (four reverse-spin perforated-twisted tapes) brings the uppermost thermal-hydraulic performance of 1.23 under Re = 8,000.

The constant thermo-hydraulic attributes of liquid water and the steady Newtonian fluid are research limitations for this simulated work.

The simulated outcomes will avail the inner-pipe design of a heat exchanger inserted by multiple perforated twisted tapes to enhance superior heat transfer.

These twisted tapes form tiny circular perforations along the tape edge to introduce the fluid flow through these bores and combine with the secondary flow induced between two reverse-spin tapes. This scheme enhances the swirling flow, turbulence intensity and fluid mixing to advance thermal convection since larger perforations cannot produce large jet velocity or the position of perforations is too far from the tape edge to generate a separated flow. Consequently, this work contributes a valuable cooling mechanism toward thermal engineering.

The purpose of this study is to analyse the magnetic field effect on Fe₃O₄/H₂O Ferrofluid flowing in a sudden expansion tube, which has specific behaviour in terms of rheology, with convex dimple fins. Because the investigation of flow separation is a prominent application in performance, the effect of magnetic field and convex dimple on the thermo-hydraulic performance of sudden expansion tube are examined, in detail.

During the solution of the boundary conditions of the sudden expansion tube, finite volume method was used. Analyses have been conducted considering the single-phase solution, steady-state, incompressible fluid and no-slip condition of the wall under forced convection conditions. In the analyses, it has been assumed that the flow was developing thermally and has been fully developed hydrodynamically.

The present study focuses on exploring the influence of the magnetic field, nanofluid concentration and convex dimple fins on the thermo-hydraulic performance of sudden expansion tube. The results indicate that the strength of the magnetic field, nanofluid concentration and convex dimple fins have a positive effect on the convective heat transfer in the system.

The authors conducted numerical studies, determining through a literature search that no one had yet investigated enhancing heat transfer on a sudden expansion tube using combinations of magnetic fields, nanofluids and convex dimple fins. The results of the numerical analyses provide valuable information about the improvement of heat transfer and system performance in electronic device cooling and heat exchangers.

Despite that a transformational shift has occurred in many organisations towards data-driven management, many organisations struggle to harness and translate new technology, such as “big data” into a competitive advantage. This study aims to undertake an empirical investigation into the enabling factors which lead to the practice of formulating an effective data-led strategy (EDLS). Leveraging the theoretical lenses of the resource-based view, absorptive capacity and attention-focus view, a range of various factors are hypothesised to influence EDLS.

The study takes place in South Africa and is based on primary survey data focused on the Fin-tech industry sector where the need to formulate and implement an EDLS has become urgent considering the move to technology enabled banking solutions. Partial Least Squares Structural Equation Modelling (PLS-SEM) is used to test the hypotheses.

Results highlight that several factors are related to EDLS as significant predictors, which include the data platform, technical skills, knowledge management, transformation and focus-alignment. This latter factor has the largest influence on EDLS, which suggests that the alignment of focus across multiple firm divisions both vertically and horizontally significantly enables an EDLS.

Managers need to appreciate the intricacy of the range of factors involved in enabling an EDLS. Managers are advised to grow their organisational knowledge regarding which enablers offer the best pathway towards the development of a more robust framework when putting an EDLS into practice.

The article offers new insights into better understanding the relevant antecedents which enable the successful practice of an EDLS from an African emerging market perspective.

This study examines the effect of non-audit fees (NAF) provisions on interest payments classification shifting. In addition, we investigate to what extent the NAF economic bonding and interest payments classification shifting is contingent on internal governance and firm financial well-being.

This study employed probit regression using a sample of UK non-financial firms indexed in FT UK (500) over the period from 2009 to 2017.

We find evidence that the economic bonding of NAF between external auditors and their clients is more likely to encourage managers in UK firms to manipulate operating cash flows through interest payment classification shifting. In addition, and interestingly, our results evince that classification-shifting may be the less costly and soft choice of managers in firms with strong governance and charging higher NAF. Furthermore, we show that financially distressed firms associated with their auditors in purchasing non-audit services are more prone to attempting to manipulate and engage in interest payments classification-shifting. Our result did not provide a significant effect of external auditor tenure on the interest payments classification shifting.

Our findings are subject to the following limitations: First, this study uses a composite index to measure the quality of internal corporate governance. It focuses only on the board of directors, but this index does not reflect other internal governance mechanisms. Second, this study is subject to limited study time due to the implementation of key IFRS standards (IFRS 9 Financial Instruments and IFRS 15 Revenue from Contract with Customers) from 2018–2019.

This study was motivated by the UK’s Financial Reporting Council regulators' pressure on the Big 4 audit firms to move more audit time into main auditing activities, reduce cross-selling to audit clients and separate their audit practices by 2024. Overall, we provide new evidence that directs a close spotlight on the threats of NAF that are potentially useful to regulators, shareholders and investors.

It is motivated by the UK’s Financial Reporting Council regulators' pressure on the Big 4 to move more audit firm time into main auditing activities, reduce cross-selling to audit clients and separate their audit practices by 2024. Overall, we provide new evidence that directs a close spotlight on the threats of NAS that are potentially useful to regulators, shareholders and investors.

To generate the measurement instrument seven steps were implemented. A total of 819 questionnaires were collected in Yunnan Province, China, where it has long tradition of eating insects.

This study aims to explore the influences of the multidimensional benefits of consuming insect-based food on its consequences. Food neophilia and hedonic motivation are used as moderating variables.

Health, nutritional value, taste and cultural domains effectively explained consumers’ attitudes toward insect-based food, food consumption value, satisfaction, subjective well-being, loyalty to the restaurant and community attachment. Food neophilia and hedonic motivation partially moderated the relationships between the proposed constructs.

This study provides a conceptual model for exploring insect-based food consumption experiences and offers a useful guideline for developing and designing marketing strategies for stakeholders in the food and restaurant industry.

This is one of the few studies examining the benefits of consuming insect-based food from the perspective of consumers.

This study aims to provide an alternative adoption to overcome the energy crisis and environmental effluence by comparative theoretical and trial testing analysis of an innovative combined condenser unit over traditional individual condenser unit water heating systems.

The presented innovative new unit of the combined condenser heat pipe works efficiently through its improved idea and unique design, providing uniform heating to improve the heat transfer and, finally, the temperature of water increases without enhancing the cost. In this design, all these five evaporator units were connected with a single combined condenser unit in such a manner that after the condensation of heat transfer fluid vapour, it goes equally into the evaporator pipe.

The maximum temperature of hot water obtained from the combined condenser heating system was 60.6, 55.5 and 50.3°C at a water flow rate of 0.001, 0.002 and 0.003 kg/s, respectively. The first and second law thermodynamic efficiency of the combined condenser heating system were 55.4%, 60.5% and 89.0% and 2.6%, 3.7% and 4.1% at 0.001, 0.002 and 0.003 kg/s of water flow rates, respectively. The combined condenser heat pipe solar evacuated tube heating system promoting progressive performance is considered efficient and environment-friendly compared to the traditional condenser unit water heating system.

Innovative combined condenser heat pipe evacuated tube collector assembly was designed and developed for the study. A comparative theoretical and experimental energy-exergy performance analysis was performed of innovated collective condenser and traditional individual condenser heat pipe water heating system at various mass flow rate.

Rapid technological change in the transport sector is leading to a growing range of potential and actual ‘business models’ deployable for the movement of goods and people. Two key uncertainties arise from this proliferation: first, concerning which ones can be economically viable, and, second, whether they can be both simultaneously economically viable and contribute to the imperatives of more sustainable mobility. The present chapter reviews and appraises the emergence of these new business models, drawing on both literature review and empirical research with entrepreneurs involved in the new mobility sector. Specifically, the potential of the UN Sustainable Development Goals (SDGs) (UN, n.d.) as a device to structure and frame the debate about what constitutes a valuable contribution to sustainable mobility is considered. A framework is developed which captures how mobility and transport have dependencies with the SDGs. From this analysis, key sustainability concepts are derived which have either a subsistence function (maintaining the basics of human life) or an enhancement function (enabling citizens to realise their potential whilst reducing impacts on the planet). Five different innovations involving mobility sector business entrepreneurship are then characterised using this framework to exemplify its ability to deconstruct and test claims that ‘smart mobility’ is also good for sustainability as well as good for business. It is concluded that the framework could contribute to a wider architecture of sustainability interrogation. It could promote discourse around a wide range of actors, posing questions and surfacing tensions and contingencies effectively, whilst providing a holistic, strategic assessment to inform more targeted, scientific evaluations of sustainability metrics.

This paper aims to examine the Canadian financial sector’s reaction to opportunities and risks created by the green bond market in a low-carbon and climate-resilient (LCR) economy.

The authors used a concurrent mixed methodological approach that undertakes an online survey and semistructured interviews with critical green bond market stakeholders.

The most significant market driver in Canada is the reputational benefit for stakeholders, i.e. its ability to meet the high demand for sustainable finance and the marketing potential of its green credentials. The major market barriers are transactional costs, i.e. additional tracking required for reporting purposes, lack of market liquidity and identification of environmental impact or additionality. Canadian green bonds are also more likely to be evaluated on their green impact than their global market peers.

Limitations of this study include its focus on Canada, which may exclude or not apply to drivers and barriers in other green bond markets.

The paper helps create an accounting-based conceptual framework for key motivations and barriers that affect financial decision-making regarding green bonds.

The authors identify economic and policy-related barriers and drivers for green bonds, addressing the financing gap for the LCR economy.

To the best of the authors’ knowledge, this study is the first to identify and compare Canadian green bond market drivers and barriers and to examine relevant stakeholder- and policy-related approaches that can be targeted to scale this market effectively.