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This study aims to present the experimental and computational performance analysis in compact plate heat exchanger (PHE) using graphene oxide nanofluids at different concentrations and flow rate.

Field emission scanning electron microscope and X-ray diffraction were used to characterize graphene oxide nanoparticles. The nanofluid samples were prepared by varying volume concentration. Zeta potential test was done to check stability of samples. The thermophysical properties of samples have been experimentally measured. The experimental setup of PHE with 60° chevron angle has also been developed. The numerical analysis is done using computational fluid dynamics (CFD) model having similar geometry as of the actual plate. Distilled water at fixed temperature and flow rate is used in hot side tank. Nanofluid at fixed temperature with varying concentration and flow rate is used in cold side tank as coolant.

The numerical and experimental results were compared and found that both results were in good agreement. The results showed ∼13% improvement in thermal conductivity, ∼14% heat transfer rate (HTR), ∼9% in effectiveness and ∼10% in overall heat transfer coefficient at cost of pressure drop and pumping power using nanofluid. Exergy loss also decreased using nanofluid at optimum concentration of 1 Vol.%.

The CFD model can be significant to analyze temperature, pressure and flow distribution in heat exchanger which is impossible otherwise. This study gives ease to predict PHE performance with high accuracy without performing the experiment.

Natural convection in a square cavity with a centrally located partition is considered. While one of the side walls is fully active, the other is partly insulated. Numerical simulation, based on the finite element method, has been carried out for different lengths of the active surface. The results have been compared with the cases when the cavity is without partition as well as the case of a partitioned cavity with fully active side walls.

The study aims to use nanofluids as coolants for improving heat transfer peculiarities of plate heat exchangers (PHE). The experimental and numerical investigations are thoroughly performed using distilled water-based Al₂O₃, graphene nanoplatelet (GnP) and multi-walled carbon nanotubes (MWCNT) nanofluids.

The numerical simulation based on Single Phase Model (SPM) was performed on a realistic 3 D model of PHE having similar dimensions as of the actual plate. The standard k-epsilon turbulent model was used to solve the problem. The concentration and flow rate of nanofluids were ranging from 0.1 to 1 Vol.% and 1 to 5 lpm, respectively, at 30°C. Whereas, hot side fluid is distilled water at 2 lpm and 80°C. The heat transfer characteristics such as bulk cold outlet temperature, heat transfer rate (HTR), heat transfer coefficient (HTC), Nusselt number (Nu), pressure drop, pumping power, effectiveness and exergy loss were experimentally evaluated using nanofluids in a PHE.

The experimental results were then compared with the numerical model. The experimental results revealed maximum enhancement in an average heat transfer rate of 9.86, 14.86 and 17.27% using Al₂O₃, GnP and MWCNT nanofluids, respectively, at 1 Vol.%. The present computational fluid dynamics model accurately predicts HTR, and the results deviate <1.1% with experiments for all the cases. The temperature and flow distribution show promising results using nanofluids.

The study helps to visualise heat transfer and flow distribution in PHE using different nanofluids under different operating conditions.

This paper aims to investigate the thermal performance of equivalent square and circular thermal systems and compare the heat transport and irreversibility of magnetohydrodynamic (MHD) nanofluid flow within these systems.

The research uses a constraint-based approach to analyze the impact of geometric shapes on heat transfer and irreversibility. Two equivalent systems, a square cavity and a circular cavity, are examined, considering identical heating/cooling lengths and fluid flow volume. The analysis includes parameters such as magnetic field strength, nanoparticle concentration and accompanying irreversibility.

This study reveals that circular geometry outperforms square geometry in terms of heat flow, fluid flow and heat transfer. The equivalent circular thermal system is more efficient, with heat transfer enhancements of approximately 17.7%. The corresponding irreversibility production rate is also higher, which is up to 17.6%. The total irreversibility production increases with Ra and decreases with a rise in Ha. However, the effect of magnetic field orientation (γ) on total EG is minor.

Further research can explore additional geometric shapes, orientations and boundary conditions to expand the understanding of thermal performance in different configurations. Experimental validation can also complement the numerical analysis presented in this study.

This research introduces a constraint-based approach for evaluating heat transport and irreversibility in MHD nanofluid flow within square and circular thermal systems. The comparison of equivalent geometries and the consideration of constraint-based analysis contribute to the originality and value of this work. The findings provide insights for designing optimal thermal systems and advancing MHD nanofluid flow control mechanisms, offering potential for improved efficiency in various applications.

An apparel supply chain primarily consists of geographically distant suppliers, manufacturers and retailers. The coordination among the members of the supply chain becomes difficult when we consider the triple bottom line of sustainability in it. Moreover, the complexity increases with the change in dominance power of the respective members. However, the task of managing the channel further becomes complicated after incorporating sustainability and dominance power simultaneously into the supply chain. To fill this gap, this paper focuses on designing of mechanism and demonstration of three-echelon model to coordinate sustainable supply chain.

In this paper, the noncooperative game theoretic method has been applied for the exploration of models. The various structures of the centralized and decentralized supply chain are considered on the basis of a player's dominance power. The model uses simultaneous and sequential move games to analyze optimal profit of supply chain agents, total channel profit, green innovation level and corporate social innovation level.

Analytical results show that simultaneous game performs better than the sequential game. The consumer sensitivity toward green and social innovations increases total channel profit. We also proposed a linear two-part tariff contract model. The proposed model enhances the sustainability level and leads to perfect channel coordination. Using a numerical example, we present the effectiveness of multiple game structures under centralized and decentralized settings. The results reveal that channel efficiency is the highest in the two-part tariff contract followed by a simultaneous move game structure and lower in the cases of sequential move game.

In this research, model setting are deterministic and there is no any information asymmetry. Therefore researchers are encouraged to study multiechelon sustainable supply chain coordination models under stochastic and information asymmetry settings.

The paper includes implications for the development of sustainable supply chain coordination model to tackle the problems of dominance power, sustainability issues and lower channel efficiency of supply chain.

This study proposes game-theory-based three-echelon sustainable supply chain for the channel coordination.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.

The purpose of the present study is to investigate the mediating effect of organizational engagement in the relationship between supportive work environment (SWE) and employee retention.

Primary data of 211 respondents from 67 organizations were analysed. Confirmatory factor analysis was used to assess the dimensionality and validity of study variables. Further, the hypothesized model was tested with the help of multiple regression analysis.

The findings suggest that SWE plays a crucial role in predicting employee retention. Organizational engagement partially mediates the relationship between SWE and employee retention.

The data were limited to the Indian setting and of cross-sectional design only; so, it may not be generalized across the world. Further, the sample size is also comparatively smaller but the results are not affected adversely.

The role of SWE along with organizational engagement is currently under-researched in the Indian context. The present study is an intense effort to analyse the mediating effect of organizational engagement in the relationship between SWE and employee retention.

The following article was published in ‘Self‐Reliance’, the Journal of The Fertiliser (Planning & Development) India Ltd., CIFT Buildings, P.O. Sindri, Pin: 828 122, Bihar, India. The author recounts how they dealt with some serious corrosion problem in the naphtha vapouriser section of an ammonia plant.