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Article
Publication date: 18 May 2010

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.

797

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.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 20 no. 4
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 13 December 2023

J. Srikanth Reddy, Ritu Sharma and Narain Gupta

The present paper concerns the domestic and international accreditations of business schools to find the commonalities in various accreditation standards. The study also addresses…

239

Abstract

Purpose

The present paper concerns the domestic and international accreditations of business schools to find the commonalities in various accreditation standards. The study also addresses cost involvement and comparisons between various accreditations.

Design/methodology/approach

The research examined the requirements, methods and preparations for many national and international accrediting authorities. The accreditation criteria, history and guidelines were collected from secondary data sources. The content analysis was used to draw conclusions about the similarities and differences between the data sources and identify any differences and similarities between various accreditations.

Findings

The study found commonalities across accreditation standards and cost analyses, helping institutions achieve suitable accreditations. To unify the administrative procedure at the institutional level and reduce duplicates for schools seeking multiple accreditations, similarities in all accreditation requirements are analysed. The comparison helps organisations determine which accreditation standard best suits their needs and goals. Schools with limited budgets might compare accreditation costs to determine which are worth pursuing.

Research limitations/implications

This study is limited to comparing a few accreditation bodies related to management education. In future research, the study may be extended to other areas. The use of the approach developed in this study for evaluating accreditation agencies of different streams, such as engineering, science and medicine, will be the study's future implications.

Practical implications

The research indicates that schools can streamline accreditation by identifying commonalities, aligning procedures, comparing standards and conducting cost assessments. These insights aid efficient accreditation and inform accrediting bodies' framework enhancements. Standards facilitate global performance comparisons.

Originality/value

This is likely the first study to compare Indian and international accreditations using the accreditation frameworks and cost analyses using comparative analysis. The study recommends strategies for achieving academic benchmarks through continuous improvement activities and success in international competition.

Details

International Journal of Educational Management, vol. 38 no. 1
Type: Research Article
ISSN: 0951-354X

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Article
Publication date: 28 March 2023

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…

262

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.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 7
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 4 November 2022

Zhiguo Tang, Feng Deng, Yongtao Ji and Jianping Cheng

The purpose of this paper is to improve the overall heat transfer performance and the temperature uniformity of the heat sink and to explore the effects of the jet Reynolds number…

171

Abstract

Purpose

The purpose of this paper is to improve the overall heat transfer performance and the temperature uniformity of the heat sink and to explore the effects of the jet Reynolds number and the nanoparticle volume fraction of the nanofluids on the flow and heat transfer performance.

Design/methodology/approach

A heat sink with discontinuous arc protrusions in the wall jet region is proposed for confined slot jet impingement. A sloping upper cover plate is added to improve the heat transfer effect in this area. An Al2O3–water nanofluid is selected as the working fluid of the jet for better heat transfer. The Standard k-e turbulence model is used for numerical calculation. The key structural parameters of the heat sink are optimized by the response surface method and a genetic algorithm. The effects of the jet Reynolds number (Re) and the nanofluid concentration (ϕ) on the flow and heat transfer performance of the optimized heat sink are investigated.

Findings

The average Nusselt number of the optimal heat sink is 8.2% higher and the friction resistance is 5.9% lower than that of the initial flat plate heat sink when ϕ = 0.02 and Re = 8,000. The discontinuous arc protrusions and the sloping upper cover plate substantially enhance the heat transfer in the later stage of jet development, improving the temperature uniformity of the heat sink. The maximum temperature difference of the optimal heat sink is 28.1% lower than that of the flat plate heat sink at the same nozzle height. As the jet Reynolds number and the nanofluid particle concentration increase, the Nusselt number of the optimized heat sink and the friction coefficients increase, resulting in a decrease in the evaluation coefficient. However, the overall temperature uniformity of the heat sink is improved under all conditions.

Originality/value

The novel heat sink structure provides a new way to enhance the heat transfer and temperature uniformity of confined slot jet impingement. The flow and heat transfer performance of the heat sink impinged by confined slot jet of nanofluids are obtained. The combination of response surface method and genetic algorithm can be applied to the multi-objective optimization of heat resistance and flow resistance of heat sink.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 3
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 7 August 2024

Funda Demir

The energy generation process through photovoltaic (PV) panels is contingent upon uncontrollable variables such as wind patterns, cloud cover, temperatures, solar irradiance…

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Abstract

Purpose

The energy generation process through photovoltaic (PV) panels is contingent upon uncontrollable variables such as wind patterns, cloud cover, temperatures, solar irradiance intensity and duration of exposure. Fluctuations in these variables can lead to interruptions in power generation and losses in output. This study aims to establish a measurement setup that enables monitoring, tracking and prediction of the generated energy in a PV energy system to ensure overall system security and stability. Toward this goal, data pertaining to the PV energy system is measured and recorded in real-time independently of location. Subsequently, the recorded data is used for power prediction.

Design/methodology/approach

Data obtained from the experimental setup include voltage and current values of the PV panel, battery and load; temperature readings of the solar panel surface, environment and the battery; and measurements of humidity, pressure and radiation values in the panel’s environment. These data were monitored and recorded in real-time through a computer interface and mobile interface enabling remote access. For prediction purposes, machine learning methods, including the gradient boosting regressor (GBR), support vector machine (SVM) and k-nearest neighbors (k-NN) algorithms, have been selected. The resulting outputs have been interpreted through graphical representations. For the numerical interpretation of the obtained predictive data, performance measurement criteria such as mean absolute error (MAE), mean squared error (MSE), root mean squared error (RMSE) and R-squared (R2) have been used.

Findings

It has been determined that the most successful prediction model is k-NN, whereas the prediction model with the lowest performance is SVM. According to the accuracy performance comparison conducted on the test data, k-NN exhibits the highest accuracy rate of 82%, whereas the accuracy rate for the GBR algorithm is 80%, and the accuracy rate for the SVM algorithm is 72%.

Originality/value

The experimental setup used in this study, including the measurement and monitoring apparatus, has been specifically designed for this research. The system is capable of remote monitoring both through a computer interface and a custom-developed mobile application. Measurements were conducted on the Karabük University campus, thereby revealing the energy potential of the Karabük province. This system serves as an exemplary study and can be deployed to any desired location for remote monitoring. Numerous methods and techniques exist for power prediction. In this study, contemporary machine learning techniques, which are pertinent to power prediction, have been used, and their performances are presented comparatively.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 18 November 2024

Mostafa Abbasi, Rahnuma Islam Nishat, Corey Bond, John Brandon Graham-Knight, Patricia Lasserre, Yves Lucet and Homayoun Najjaran

The significance of business processes has fostered a close collaboration between academia and industry. Moreover, the business landscape has witnessed continuous transformation…

163

Abstract

Purpose

The significance of business processes has fostered a close collaboration between academia and industry. Moreover, the business landscape has witnessed continuous transformation, closely intertwined with technological advancements. Our main goal is to offer researchers and process analysts insights into the latest developments concerning artificial intelligence (AI) and machine learning (ML) to optimize their processes in an organization and identify research gaps and future directions in the field.

Design/methodology/approach

In this study, we perform a systematic review of academic literature to investigate the integration of AI/ML in business process management (BPM). We categorize the literature according to the BPM life-cycle and employ bibliometric and objective-oriented methodology to analyze related papers.

Findings

In business process management and process map, AI/ML has made significant improvements using operational data on process metrics. These developments involve two distinct stages: (1) process enhancement, which emphasizes analyzing process information and adding descriptions to process models and (2) process improvement, which focuses on redesigning processes based on insights derived from analysis.

Research limitations/implications

While this review paper serves to provide an overview of different approaches for addressing process-related challenges, it does not delve deeply into the intricacies of fine-grained technical details of each method. This work focuses on recent papers conducted between 2010 and 2024.

Originality/value

This work addresses a significant gap by employing a pioneering approach to introduce challenges in BPM alongside AI/ML techniques and integrated tools. Hence, it offers comprehensive guidelines that elucidate the alignment between ML methods and solutions to current challenges across the BPM life-cycle, including process enhancement and process improvement. Additionally, by detailing various aspects of the life-cycle phases and highlighting ML technique characteristics, this research demonstrates potential approaches for future exploration, thereby enhancing applicability for both process analysts and researchers in this context.

Details

Business Process Management Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1463-7154

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Article
Publication date: 28 February 2023

Sivasankaran Sivanandam and Bhuvaneswari Marimuthu

The numerical analysis is to scrutinize the collective effect of convective current along with the thermal energy transport in an inclined lid-driven square chamber with sine…

90

Abstract

Purpose

The numerical analysis is to scrutinize the collective effect of convective current along with the thermal energy transport in an inclined lid-driven square chamber with sine curve based temperature at the lower wall in the existence of unchanging external magnetic field. Insulation has been placed on the left and right of the box to increase the effective space volume of the shell. The thermal condition at ceiling wall is kept lower than the one on the floor.

Design/methodology/approach

The finite volume method employs to discretize (non-dimensional) system of equations govern the model. The heat transfer rate is measured by adjusting various variables, such as the Richardson number Hartmann number, inclination of an enclosure.

Findings

The flow behavior of enclosure convection is more highly influenced within the natural convection when enclosure inclination varies as well as magnetic field strength. The overall heat transfer rate decreases due to increase in both the Hartmann number as well as Richardson number.

Practical implications

The results of the present study are very useful to the cooling of electronic equipments.

Social implications

The study model is useful to the thermal science community and modelling field.

Originality/value

This research is a novel work on mixed convection flow in an inclined chamber with sinusoidal heat source.

Details

Multidiscipline Modeling in Materials and Structures, vol. 19 no. 3
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 14 March 2016

BM Viswanatha, M Prasanna Kumar, S Basavarajappa and TS Kiran

This paper aims to investigate the microstructure, hardness and tribological properties of hypoeutectic (Al-7Si) matrix reinforced with fixed quantities of 3 Wt.% graphite (Gr…

168

Abstract

Purpose

This paper aims to investigate the microstructure, hardness and tribological properties of hypoeutectic (Al-7Si) matrix reinforced with fixed quantities of 3 Wt.% graphite (Gr) and x Wt.% SiCp (x = 3, 6 and 9) hybrid composites.

Design/methodology/approach

The composites were fabricated by stir cast technique. The microstructure, hardness and tribological measurements were carried out on the base alloy and composites. The tribological investigation was carried out on pin-on-disc wear testing machine under dry sliding condition.

Findings

The wear rate decreases with the increase of SiCp into A356-3Gr composites. The composite containing A356-9SiCp-3Gr had better hardness and good wear resistance compared to the base alloy. Scanning electron microscope (SEM) and electro dispersive spectrometry (EDS) images were used to study the reinforcement distribution and worn-out surface of the specimens.

Originality/value

The present paper brings out a clear picture of the various events that take place under the worn-out surfaces leading to the generation of mechanical mixed layer.

Details

Industrial Lubrication and Tribology, vol. 68 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 4 February 2014

Aleksandar Vencl, Ilija Bobic and Blaza Stojanovic

Aluminium alloys are frequently applied in automotive and other industries, since they provide mass reduction. Besides positive effects, aluminium alloys have their shortcomings…

323

Abstract

Purpose

Aluminium alloys are frequently applied in automotive and other industries, since they provide mass reduction. Besides positive effects, aluminium alloys have their shortcomings reflected, first of all, in inappropriate tribological properties of these materials. The aim of this research was to enable the production of cheap aluminium alloy matrix composite with favourable combination of structural, mechanical and tribological properties, focusing on the tribological behaviour.

Design/methodology/approach

The A356 Al-Si alloy was used as a matrix for producing metal matrix composites in compocasting process. Three different materials, in form of particles, were added to the matrix (Al2O3, SiC and graphite). Hardness and tribological properties (wear, friction and wear mechanism) of heat-treated (T6) samples were examined and compared. Tribological tests were carried out on ball-on-block tribometer under dry sliding conditions. Sliding was linear (reciprocating). Counter body was alumina ball. Average velocity was 0.038 m/s (max. 0.06 m/s), sliding distance was 500 m and normal load was 1 N.

Findings

The effect of two different ceramic particles and graphite particles on tribological properties of obtained composites was evaluated. Wear resistance of composites reinforced with SiC particles was higher and coefficient of friction was lower compared to the composite reinforced with Al2O3 particles. A dual hybrid composite (with SiC and graphite particles) showed the lowest value of wear rate and friction coefficient. Dominant wear mechanism for all tested material was adhesion.

Research limitations/implications

It seems useful to continue the work on developing hybrid composites containing soft graphite particles with A356 Al-Si alloy as matrix. The major task should be to improve particles distribution (especially with higher graphite content) and to explore tribological behaviour in diverse working conditions.

Originality/value

Particulate composites with A356 aluminium alloy as a matrix produced in compocasting process using ceramic particles (Al2O3, SiC) were investigated in many researches, but there are only few detailed analyses of dual composites (with the addition of ceramic and graphite particles). In some previous studies, it was shown that compocasting process, as relatively cheap technology, can obtain good structural and mechanical characteristics of composites. In this study, it was shown that even a low graphite content, under specified conditions, can improve tribological properties.

Details

Industrial Lubrication and Tribology, vol. 66 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 8 May 2018

Viswanatha B.M., M. Prasanna Kumar, S. Basavarajappa and T.S. Kiran

This paper aims to investigate the wear behaviors of aged metal matrix composites and of the as-cast Al-Si alloy by using a pin-on-disk wear testing machine at room temperature.

134

Abstract

Purpose

This paper aims to investigate the wear behaviors of aged metal matrix composites and of the as-cast Al-Si alloy by using a pin-on-disk wear testing machine at room temperature.

Design/methodology/approach

Hypoeutectic (Al-7Si) alloy reinforced with low volume fractions of SiC particles (SiCp) and graphite (Gr) particles were prepared by the stir-casting process. It was found that the addition of 9 Wt.% of SiCp and 3 Wt.% of Gr particles conferred a beneficial effect in reducing the wear rate of the composites.

Findings

The worn-out surfaces of the specimens were examined using scanning electron microscopy (SEM); the extensive micro cracking occurs on the surface of the Al-7Si alloy tested at lower loads. The growth of these microcracks finally led to the delamination of the base alloy surface. The reinforcements (SiCp and Gr) particles tended to reduce the extent of plastic deformation in the surface layer, thereby reducing extensively the occurrence of micro cracking in the composites.

Originality/value

From the results, it is revealed that the quantity of wear rate was less for aged specimens compared to the as-cast specimens. The worn-out surfaces were studied using electron dispersive spectroscopy, and wear debris was analyzed using SEM.

Details

Industrial Lubrication and Tribology, vol. 70 no. 4
Type: Research Article
ISSN: 0036-8792

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