M. Mustafa, Ammar Mushtaq, T. Hayat and A. Alsaedi
This study aims to deal with the laminar flow owing to rough rotating disk in the existence of vertical magnetic field and partial slip effects. The aim is to resolve heat…
Abstract
Purpose
This study aims to deal with the laminar flow owing to rough rotating disk in the existence of vertical magnetic field and partial slip effects. The aim is to resolve heat transfer problem in the existence of non-linear radiative flux and thermal slip effects. The study also analyzes the mass transfer process when the flow field contains chemically reacting species.
Design/methodology/approach
Modified von-Kármán transformations are applied to change the conservation equations into similar forms. The transformed equations are treated by a convenient shooting method and by contemporary built in routine bvp4c of MATLAB.
Findings
The numerical solutions are used to address the role of main ingredients of the problem, namely, wall roughness, radiation and chemical reaction on the flow fields.
Research limitations/implications
Temperature profiles are considerably affected by a parameter measuring wall to ambient temperature ratio. Furthermore, behavior of concentration field is highly influenced by the reaction rate of the diffusing species.
Originality/value
The concept of non-linear radiation in chemically reactive flow over a rotating disk is just introduced here.
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M. Mustafa, Ammar Mushtaq, T. Hayat and A. Alsaedi
The purpose of this paper is to investigate non-linear radiation heat transfer problem for stagnation-point flow of non-Newtonian fluid obeying the power-law model. Power-law…
Abstract
Purpose
The purpose of this paper is to investigate non-linear radiation heat transfer problem for stagnation-point flow of non-Newtonian fluid obeying the power-law model. Power-law fluids of both shear-thinning and shear-thickening nature have been considered.
Design/methodology/approach
Boundary layer equations are non-dimensionalized and then solved for the numerical solutions by fourth-fifth order Runge-Kutta integration based shooting technique.
Findings
The results reveal an existence of point of inflection for the temperature distribution for sufficiently large wall to ambient temperature ratio. Moreover temperature increases and heat transfer from the plate decreases with an increase in the radiation parameter. Heat transfer rate at the sheet is bigger in dilatant (shear-thickening) fluids when compared with the pseudoplastic (shear-thinning) fluids.
Originality/value
Different from the linear radiation heat transfer problem (which can be simply reduced to rescaling of Prandtl number by a factor containing the radiation parameter), here the energy equation is strongly non-linear and it involves an additional temperature ratio parameter w=T w/T ∞. This parameter allows studying the thermal characteristics for small/large temperature differences in the flow.
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Ammar Mushtaq, M. Mustafa, T. Hayat and A. Alsaedi
– The purpose of this paper is to consider a laminar two-dimensional incompressible flow of an electrically conducting fluid over a moving flat plate with a parallel free stream.
Abstract
Purpose
The purpose of this paper is to consider a laminar two-dimensional incompressible flow of an electrically conducting fluid over a moving flat plate with a parallel free stream.
Design/methodology/approach
The governing equations are first reduced into self-similar forms and then solved for the numerical solutions by shooting method.
Findings
The results are compared with the available studies is some special cases and found in excellent agreement. It is noticed that an increase in the magnetic field strength leads to a decrease in the momentum boundary layer thickness and enhancement in the rate of heat transfer from the plate. It is also observed that temperature and heat transfer from the plate increase when radiation effect is strengthened.
Originality/value
A recently proposed idea of nonlinear radiative heat transfer with Joule heating and viscous dissipation effects is analyzed.
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Yanen Wang, Ray Tahir Mushtaq, Ammar Ahmed, Ammar Ahmed, Mudassar Rehman, Mudassar Rehman, Aqib Mashood Khan, Shubham Sharma, Dr Kashif Ishfaq, Haider Ali and Thierno Gueye
Additive manufacturing (AM) technology has a huge influence on the real world because of its ability to manufacture massively complicated geometrics. The purpose of this study is…
Abstract
Purpose
Additive manufacturing (AM) technology has a huge influence on the real world because of its ability to manufacture massively complicated geometrics. The purpose of this study is to use CiteSpace (CS) visual analysis to identify fused deposition modeling (FDM) research and development patterns to guide researchers to decide future research and provide a framework for corporations and organizations to prepare for the development in the rapid prototyping industry. Three-dimensional printing (3DP) is defined to budget minimize manufactured input and output for aviation and the medical product industrial sectors. 3DP has implemented its potential in the Coronavirus Disease of 2019 (COVID-19) reaction.
Design/methodology/approach
First, 396 original publications were extracted from the web of science (WOS) with the comprehensive list and did scientometrics analysis in CS software. The parameters are specified in CS including the span (from 2011 to 2019, one year slice for the co-authorship and the co-accordance analysis), visualization (show the merged networks), specific criteria for selection (top 20%), node form (author, organization, region, reference cited; cited author, journal and keywords) and pruning (pathfinder and slicing network). Finally, correlating data was studied and showed the results of the visualization study of FDM research were shown.
Findings
The framework of FDM information is beginning to take shape. About hot research topics, there are “Morphology,” “Tensile Property by making Blends,” “Use of Carbon nanotube in 3DP” and “Topology optimization.” Regarding the latest research frontiers of FDM printing, there are “Fused Filament Fabrication,” “AM,” in FDM printing. Where “Post-processing” and “environmental impact” are the research hotspots in FDM printing. These research results can provide insight into FDM printing and useful information to consider the existing studies and developments in FDM researchers’ analysis.
Research limitations/implications
Despite some important obtained results through FDM-related publications’ visualization, some deficiencies remain in this research. With >99% of articles written in English, the input data for CS was all downloaded from WOS databases, resulting in a language bias of papers in other languages and neglecting other data sources. Although, there are several challenges being faced by the FDM that limit its wide variety of applications. However, the significance of the current work concerning the technical and engineering prospects is discussed herein.
Originality/value
First, the novelty of this work lies in describing the FDM approach in a Scientometric way. In Scientometric investigation, leading writers, organizations, keywords, hot research and emerging knowledge points were explained. Second, this research has thoroughly and comprehensively examined the useful sustainability effects, i.e. economic sustainability, energy-based sustainability, environmental sustainability, of 3DP in industrial development in qualitative and quantitative aspects by 2025 from a global viewpoint. Third, this work also described the practical significance of FDM based on 3DP since COVID-19. 3DP has stepped up as a vital technology to support improved healthcare and other general response to emergency situations.
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Mudassar Rehman, Yanen Wang, Kashif Ishfaq, Haiou Yang, Ray Tahir Mushtaq, M. Saravana Kumar and Ammar Ahmed
Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term…
Abstract
Purpose
Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term implantation. Therefore, the fine process tuning plays its crucial role to develop optimal settings to achieve these desired properties. This paper aims to find applications for fine process tuning in laser powder bed fusion of biomedical Ti alloys for load-bearing implants.
Design/methodology/approach
In this work, the parametric porosity simulations were initially performed to simulate the process-induced porosity for selective laser-melted Ti6Al4V as per full factorial design. Continually, the experiments were performed to validate the simulation results and perform multiresponse optimization to fine-tune the processing parameters. Three levels of each control variable, namely, laser power – Pl (180, 190, 200) W, scanning speed – Vs (1500, 1600, 1700) mm/s and scan orientation – ϴ{1(0,0), 2(0,67°), 3(0,90°)} were used to investigate the processing performance. The measured properties from this study include compressive yield strength, elastic modulus, process-induced porosity and surface roughness. Finally, confirmatory experiments and comparisons with the already published works were also performed to validate the research results.
Findings
The results of porosity parametric simulation and experiments in selective laser melting of Ti6Al4V were found close to each other with overall porosity (less than 10%). The fine process tuning was resulted in optimal settings [Pl (200 W), Vs (1500 mm/s), ϴ (0,90°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,67°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] and [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] with higher compressive strength (672.78 MPa), near cortical bone elastic modulus (12.932 GPa), process-induced porosity (0.751%) and minimum surface roughness (2.72 µm). The morphology of the selective laser melted (SLMed) surface indicated that the lack of fusion pores was prominent because of low laser energy density among the laser and powder bed. Confirmatory experimentation revealed that an overall percent improvement of around 15% was found between predicted and the experimental values.
Originality/value
Since no significant works are available on the collaborative optimization and fine process tuning in laser powder bed fusion of biomedical Ti alloys for different load bearing implants. Therefore, this work involves the comprehensive investigation and multi-objective optimization to determine optimal parametric settings for better mechanical and physical properties. Another novel aspect is the parametric porosity simulation using Ansys Additive to assist in process parameters and their levels selection. As a result, selective laser melted Ti alloys at optimal settings may help in examining the possibility for manufacturing metallic implants for load-bearing applications.
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The objective of this study was to look closely at how domestic violence is represented in Pakistani drama serials to see if portrayals are reinforcing stereotypical and/or…
Abstract
Purpose
The objective of this study was to look closely at how domestic violence is represented in Pakistani drama serials to see if portrayals are reinforcing stereotypical and/or patriarchal values, or breaking the rigid norms.
Design/methodology/approach
With the help of dispositive analysis within the critical discourse approach, the prominent and non-dominant discourses about domestic violence were identified and discussed. Episodes from two popular drama serials, Kaisa Yeh Naseeban and Khaas, released in 2019, were watched with special focus on texts on domestic violence alongside objects and actions.
Findings
Analysis showed that both drama serials gave importance to socio-systemic and liberal humanist instrumentalism discourses, which describe domestic violence as a result of social structures and that abuse is used to assert control, respectively. However, some instances were noted where patriarchal values were encouraged.
Originality/value
As media has become a powerful tool of influence and awareness in the recent times, it is imperative that the content watched on it by millions of people be studied and analyzed. It is claimed that Pakistani drama serials with wide following and that are made on social issues around women aim to raise awareness and empower them. Domestic violence is a prevalent issue in Pakistan, and no research till date has examined representation of domestic violence on Pakistani popular media, which may influence response to domestic violence, which this paper aims to do.
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Management writings in the Middle East region are scarce and scattered. This is due to the lack of doctorate programmes offered by educational institutions, the weak links between…
Abstract
Management writings in the Middle East region are scarce and scattered. This is due to the lack of doctorate programmes offered by educational institutions, the weak links between academia and the business world, limited formal and informal networks, the lack of status given to the field of management by national bodies and the lack of a publication culture. A bibliography of management‐related writings in the Middle East is presented, which includes other functional areas such as marketing, finance and accounting. It aims to draw the students' attention to a variety of sources. In compiling the bibliography a review of the literature in Arabic, English and Turkish was undertaken, followed by a survey of the top officials of academic institutions offering management/commerce, business administration degree programmes in the region.
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V. Chowdary Boppana and Fahraz Ali
This paper presents an experimental investigation in establishing the relationship between FDM process parameters and tensile strength of polycarbonate (PC) samples using the…
Abstract
Purpose
This paper presents an experimental investigation in establishing the relationship between FDM process parameters and tensile strength of polycarbonate (PC) samples using the I-Optimal design.
Design/methodology/approach
I-optimal design methodology is used to plan the experiments by means of Minitab-17.1 software. Samples are manufactured using Stratsys FDM 400mc and tested as per ISO standards. Additionally, an artificial neural network model was developed and compared to the regression model in order to select an appropriate model for optimisation. Finally, the genetic algorithm (GA) solver is executed for improvement of tensile strength of FDM built PC components.
Findings
This study demonstrates that the selected process parameters (raster angle, raster to raster air gap, build orientation about Y axis and the number of contours) had significant effect on tensile strength with raster angle being the most influential factor. Increasing the build orientation about Y axis produced specimens with compact structures that resulted in improved fracture resistance.
Research limitations/implications
The fitted regression model has a p-value less than 0.05 which suggests that the model terms significantly represent the tensile strength of PC samples. Further, from the normal probability plot it was found that the residuals follow a straight line, thus the developed model provides adequate predictions. Furthermore, from the validation runs, a close agreement between the predicted and actual values was seen along the reference line which further supports satisfactory model predictions.
Practical implications
This study successfully investigated the effects of the selected process parameters - raster angle, raster to raster air gap, build orientation about Y axis and the number of contours - on tensile strength of PC samples utilising the I-optimal design and ANOVA. In addition, for prediction of the part strength, regression and ANN models were developed. The selected ANN model was optimised using the GA-solver for determination of optimal parameter settings.
Originality/value
The proposed ANN-GA approach is more appropriate to establish the non-linear relationship between the selected process parameters and tensile strength. Further, the proposed ANN-GA methodology can assist in manufacture of various industrial products with Nylon, polyethylene terephthalate glycol (PETG) and PET as new 3DP materials.
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Muhammad Sohail, Rahila Naz and Rabeeah Raza
The purpose of this paper is to address the entropy analysis of the 3D flow of Maxwell nanofluid containing gyrotactic microorganism in the presence of homogeneous–heterogeneous…
Abstract
Purpose
The purpose of this paper is to address the entropy analysis of the 3D flow of Maxwell nanofluid containing gyrotactic microorganism in the presence of homogeneous–heterogeneous reactions with improved heat conduction and mass diffusion models over a stretched surface. Improved models are supported out by utilizing Cattaneo–Christov heat flux and generalized Fick’s law, respectively.
Design/methodology/approach
Governing equations which present the given flow phenomenon are modeled in the form of PDEs by applying boundary layer analysis and then suitable makeovers are engaged to transfigure prevailing partial differential equations into a set of ordinary differential equations. Transformed equations are handled via optimal homotopy analysis process in computational tool Mathematica and also a special case of already published work is substantiated and found to be in excellent settlement.
Findings
The bearing of innumerable convoluted physical parameters on velocity, temperature, concentration, reaction rate, the concentration of motile microorganism and entropy generation are presented and deliberated through graphs. Moreover, the convergence of the homotopic solution is presented in tabular form which confirms the reliability of the proposed scheme. It is perceived that mounting values of the magnetic parameter and Brinkman number boosts the irreversibility analysis and Bejan number diminishes for these parameters. Moreover, the growing values of Prandtl and Schmidt numbers reduce the temperature and concentration fields, respectively.
Practical implications
The work contained in this paper has applications in a different industry.
Originality/value
The work contained in this paper is original work and it is good for the researcher in the field of applied mathematics.
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A.M. Mohamad, Dhananjay Yadav, Mukesh Kumar Awasthi, Ravi Ragoju, Krishnendu Bhattacharyya and Amit Mahajan
The purpose of the study is to analytically as well as numerically investigate the weight of throughflow on the onset of Casson nanofluid layer in a permeable matrix. This study…
Abstract
Purpose
The purpose of the study is to analytically as well as numerically investigate the weight of throughflow on the onset of Casson nanofluid layer in a permeable matrix. This study examines both the marginal and over stable kind of convective movement in the system.
Design/methodology/approach
A double-phase model is used for Casson nanofluid, which integrates the impacts of thermophoresis and Brownian wave, whereas for flow in the porous matrix the altered Darcy model is occupied under the statement that nanoparticle flux is disappear on the boundaries. The resultant eigenvalue problem is resolved analytically as well as numerically with the help of Galerkin process with the Casson nanofluid Rayleigh–Darcy number as the eigenvalue.
Findings
The findings revealed that the throughflow factor postpones the arrival of convective flow and reduces the extent of convective cells, whereas the Casson factor, the Casson nanoparticle Rayleigh–Darcy number and the reformed diffusivity ratio promote convective motion and also decrease the extent of convective cells.
Originality/value
Controlling the convective movement in heat transfer systems that generate high heat flux is a real mechanical challenge. The proposed framework proved that the use of throughflow is one of the most important ways to control the convective movement in Casson nanofluid. To the best of the authors’ knowledge, no inspection has been established in the literature that studies the outcome of throughflow on the Casson nanofluid convective flow in a porous medium layer. However, the convective flow of Casson nanofluid finds many applications in improving heat transmission and energy efficiency in a range of thermal systems, such as the cooling of heat-generating elements in electronic devices, heat exchangers, pharmaceutical practices and hybrid-powered engines, where throughflow can play a significant role in controlling the convective motion.