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The purpose of this work is to highlight the effects of partial unipolar injection on electro-thermo-convection (ETC) in dielectric liquid contained between two eccentric cylinders.

A finite volume method was used to solve governing equations. The study is performed for different parameters, such as radius ratio (0.2 ≤ Γ ≤ 0.6), dimensionless electric Rayleigh number (0 ≤ T ≤ 900), eccentricity (−0.4 ≤ e ≤ 0.4) and thermal Rayleigh number (10 ≤ Ra ≤ 5.105).

It is found that heat transfer increases with increase in dimensionless electric Rayleigh number and eccentricity ratio.

The originality of this work is to analyze the ETC in dielectric liquid subjected to partial unipolar injection between two eccentric cylinders

The purpose of this paper is to investigate the coupled effect of magnetic field and radiation on convective heat transfer of low electrically conductive dielectric oxide melt.

The 3D Navier–Stokes equations are formulated using the vector potential-vorticity formulation and solved using the finite volume method (FVM). The radiative heat transfer equation is discretized using the FTnFVM method. A code was written using FORTRAN language.

The obtained numerical results are focused on the effect of the different parameters on the heat transfer and the flow structure with a special interest on the 3D transvers flow. It is found that the flow is developing in inner spirals and the magnetic field intensifies this 3D character. The radiation acts mainly at the core of the enclosure and causes the apparition of the merging phenomenon near the front and back walls.

The effect of magnetic field on convective heat transfer of highly electrically conductive fluids has been intensively studied. Reciprocally, the case of a fluid with low electrical conductivity is not so much investigated, especially when it is coupled with the effect of radiation. These two effects are studied in this paper for the case of a low-conductive LiNbO3 oxide melt.

The purpose of this paper is to highlight the advantages of a simplified algorithm to solve the problem of heat and mass transfer in porous medium by reducing the number of partial differential equations from four to three.

The approach of the present paper is to develop a simplified algorithm to reduce the number of equations involved in conjugate heat transfer in porous medium.

Developed algorithm/method has many advantages over conventional method of solution for conjugate heat transfer in porous medium.

The current work is applicable to conjugate heat transfer problem.

The developed algorithm is useful in reducing the number of equations to be solved, thus reducing the computational resources required.

Development of simplified algorithm and comparison with conventional method.

This study aims to investigate a three-dimensional computational modelling of free convection of Al₂O₃ water-based nanofluid in a cylindrical cavity under heterogeneous heat fluxes that can be used as a thermal storage tank.

Effects of different heat flux boundary conditions on heat transfer and entropy generation were examined and the optimal configuration was identified. The simulation results for nanoparticle (NP) volume fractions up to 4 per cent, and Rayleigh numbers of 10⁴, 10⁵ and 10⁶ were presented.

The results showed that for low Ra (10⁴) the heat transfer and entropy generation patterns were symmetric, whereas with increasing the Rayleigh number these patterns became asymmetric and more complex. Therefore, despite the symmetric boundary conditions imposed on the periphery of the enclosure (uniform in Ɵ), it was necessary to simulate the problem as three-dimensional instead of two-dimensional. The simulation results showed that by selecting the optimal values of heat flux distribution and NP volume fraction for these systems the energy consumption can be reduced, and consequently, the energy efficiency can be ameliorated.

The results of the present study can be used for the design of energy devices such as thermal storage tanks, as both first and second laws of thermodynamics have been considered. Using the optimal design will reduce energy consumption.

The purpose of this study is to present a comprehensive hydrothermal analysis on an inclined mini-channel using numerical and experimental techniques. The fin array acts as heat source within the channel, and a wavy wall located at the top of the channel is heat sink. The side walls are insulated with curved profiles. Also, the channel is inclined with four known inclination angles. To solve the governing equations, the dual-multi-relaxation-time lattice Boltzmann method with D2Q9 and D2Q5 lattice models for flow and temperature fields is used, respectively. Also, the channel is filled with SiO2-glycol nanofluid.

Identifying the behavior of a thermal component during natural convective flow is a challenging topic due to its complexities. This paper focuses on analyzing the thermal and hydrodynamic aspects of a narrow channel equipping with fin array.

Two correlations are proposed considering temperature and volume fraction ranges for thermal conductivity and dynamic viscosity according to measured experimental data which are used in the numerical phase. Finally, the structure of flow, temperature distribution of fluid, local thermal and viscous dissipations, volume-averaged entropy production, Bejan number and heat transfer rate are extracted by numerical simulations. The results show that the average Nusselt number enhances about 57% (maximum enhancement percentage) when volume fraction increases from 1% to 3% at Ra = 10⁶ and θ = 90°. In addition, the value of entropy generation is maximum at φ = 1%, Ra = 10⁶ and φ = 90°. Also, the maximum enhancement of entropy generation in range of Ra = 103 to 106 is about 4 times at φ = 1% and θ = 90°.

The originality of the present study is combining a modern numerical method (i.e. dual/multi-relaxation-time LBM) with experimental observation on characteristics of SiO₂-glycol nanofluid to study the thermal and hydrodynamic properties of the studied mini-channel.

The purpose of this paper is to develop a wireless positioning system. The automation of non-destructive testing (NDT) of large and complex geometry structures such as aircraft wings and fuselage is prohibitively expensive, though automation promises to improve on manual ultrasound testing. One inexpensive way to achieve automation is by using a small wall-climbing mobile robot to move a single ultrasound probe over the surface through a scanning trajectory defined by a qualified procedure. However, the problem is to guide the robot though the trajectory and know whether it has followed it accurately to confirm that the qualified procedure has been carried out.

The approach is to use sophisticated bulk electronics developed for game playing in combination with MATLAB to develop a wireless positioning system.

The paper describes the development of an inexpensive wireless system comprising an optical spatial positioning system and inertial measurement unit that relates the 3D location of an NDT probe carried by a mobile robot to a computer-aided drawing (CAD) representation of the test structure in a MATLAB environment. The probe is located to an accuracy of ± 2 mm at distances of 5 m.

Positioning range is limited to 5 m. Further development is required to increase this range.

The wireless system is used to develop tools to guide the robot remotely to follow a desired scanning trajectory, obtain feedback about the actual trajectory executed by the robot, know exactly where an ultrasound pulse echo was captured, map identified defects on the CAD and relate them to the real test object.

An inexpensive spatial positioning system with sufficient accuracy for automated NDT purposes.

The present study investigates the moderating role of customer trust in customer relationship management (CRM) components and customer loyalty relationships in the context of the baking sector in Bangladesh.

Data were collected through a survey using a structured questionnaire from 350 customers of commercial banks in Bangladesh.

The key finding is that all CRM components (customer orientation, customer advocacy and customer knowledge) except customer engagement have positive impact on customer loyalty. Moreover, customer trust only moderates the relationship between customer knowledge and customer loyalty, whereas other CRM components and customer loyalty do not moderate by trust.

The findings of the study add to the substantial pool of knowledge on CRM components, customer trust and customer loyalty literature. More specifically, the moderating role of customer trust between customer knowledge and customer loyalty is the novel contribution of this research which will enrich the existing CRM literature particularly in the banking sector of Bangladesh.

This study aims to provide an insight into research related to Muslim travellers in the past 42 years.

Using 342 articles collected from the Scopus database from 1981 to 2023, this study adopted the Bibliometrix in RStudio package and Biblioshiny Web application to analyse the research on Muslim travellers in two main categories: overview and intellectual structures.

The first publication related to Muslim travellers occurred in 1981 and number of publications remained few in the first three decades. Starting 2015, publications on Muslim travellers experienced a growing development of discussions and publications. Four prominent research clusters were identified: “halal tourism”, “hajj”, “Islamic tourism” and “tourist post-purchase”. Themes within the research on Muslim travellers have evolved from the “pilgrimage” to “Islamic tourism” theme. Then, the “Islamic tourism” theme has been expanded to a variety of topics that were primarily relevant to Muslim tourist behaviour. Themes related to “climate change” and “Syria” have been identified as the niche themes that need further study.

Scopus database is regularly updated as the number of papers and journals may increase or decrease from time to time. This may impact on the fluctuation of the theme analysis from the article search at that time.

This study reviews publications related to Muslim travellers over the past four decades. Accordingly, it can aid interested researchers and stakeholders in gaining a more thorough understanding of Muslim traveller research.

The purpose of this study was to analyze the heat transfer in a square porous cavity that has a solid block placed at its center. The prime focus of this study is to investigate the effect of size of the square solid block and other physical parameters on the heat transfer rate from the hot surface into the porous medium. The left vertical surface of cavity is maintained at a hot temperature and the right vertical surface at a cool temperature, T_c. The finite element method is used to simplify the governing equations and is solved iteratively. It is noted that the size of the solid block plays a vital role in dictating the heat transfer from the hot surface to porous medium.

The current work is based on finite element formulation of a square porous cavity that has a solid square block placed at its center. Governing equations were solved iteratively.

The size of the solid block has a pronounced effect on the heat transfer behavior inside the porous cavity.

This study highlights the heat transfer due to a conducting square solid block at mid of porous cavity.

This study aims to numerically investigate the thermal-hydrodynamic performance of silicon oxide/water nanofluid laminar flow in the heat sink miniature channel with different fin cross-sections. The effect of the fin cross-section including semi-circular, rectangular and quadrant in two directions of flat and curved, and channel substrate materials of steel, aluminum, copper and titanium were examined. Finally, the analysis of thermal and frictional entropy generation in different channels is performed.

According to the numerical results, the highest heat transfer coefficients belong to the rectangular, quadrant 2, quadrant 1 and semi-circular fins compared to the channel without fin is 38.65%, 29.94%, 27.45% and 17.1%, respectively. Also, the highest performance evaluation criteria belong to the rectangular and quadrant 2 fins, which have 1.35 and 1.29, respectively. Based on the thermal conductivity of the substrate material, the best material is copper. According to the results of entropy analysis, the reduction of thermal irreversibility of the channel with rectangular, quadrant 1, quadrant 2 and semi-circular compared to non-finned channel is equal to 72%, 57%, 63% and 48%, respectively.

The rectangular and quadrant 2 fins are the best fins and the copper substrate material is the best material to reduce the entropy generation.

The silicon oxide/water nanofluid flow in the heat sink miniature channel with various fin shapes and the curvature angle against the fluid flow was simulated to increase the heat transfer performance. The whole test section is simulated in three-dimensional. Different channel materials have been investigated to find the best channel substrate material.