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Article
Publication date: 6 November 2017

Irfan Anjum Badruddin, Azeem Khan, Mohd Yamani Idna Idris, N. Nik-Ghaali, Salman Ahmed N.J. and Abdullah A.A.A. Al-Rashed

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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

Research limitations/implications

The current work is applicable to conjugate heat transfer problem.

Practical implications

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

Originality/value

Development of simplified algorithm and comparison with conventional method.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 11
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 1 June 2021

S.V. Khandal, T.M. Yunus Khan, Sarfaraz Kamangar, Maughal Ahmed Ali Baig and Salman Ahmed N J

The different performance tests were conducted on diesel engine compression ignition (CI) mode and CRDi engine.

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Abstract

Purpose

The different performance tests were conducted on diesel engine compression ignition (CI) mode and CRDi engine.

Design/methodology/approach

The CI engine was suitably modified to CRDi engine with Toroidal re-entrant combustion chamber (TRCC) and was run in dual-fuel (DF) mode. Hydrogen (H2) was supplied at different flow rates during the suction stroke, and 0.22 Kg/h of hydrogen fuel flow rate (HFFR) was found to be optimum. Diesel and biodiesel were used as pilot fuels. The CRDi engine with DF mode was run at various injection pressures, and 900 bar was found to be optimum injection pressure (IP) with 10o before top dead center (bTDC) as fuel injection timing (IT).

Findings

These operating engine conditions increased formation of oxides of nitrogen (NOx), which were reduced by exhaust gas recycle (EGR). With EGR of 15%, CRDi engine resulted in 12.6% lower brake thermal efficiency (BTE), 5.5% lower hydrocarbon (HC), 7.7% lower carbon monoxide (CO), 26% lower NOx at 80% load as compared to the unmodified diesel engine (CI mode).

Originality/value

The current research is an effort to study and evaluate the performance of CRDi engine in DF mode with diesel-H2 and BCPO-H2 fuel combinations with TRCC.

Details

Frontiers in Engineering and Built Environment, vol. 1 no. 1
Type: Research Article
ISSN: 2634-2499

Keywords

Article
Publication date: 9 October 2019

Mohammed Fahimuddin Mulla, Irfan Anjum Badruddin, N. Nik-Ghazali, Mohammed Ridha Muhamad, Ahamed Saleel C. and Poo Balan Ganesan

This paper aims to investigate the heat transfer in porous channels.

Abstract

Purpose

This paper aims to investigate the heat transfer in porous channels.

Design/methodology/approach

Finite element method is used to simulate the heat transfer in porous channels.

Findings

The number and width of channels play a key role in determining the heat transfer of the porous channel. The heat transfer is higher around the channel legs. Smaller base height is better to get higher heat transfer capability.

Originality/value

This study represents the original work to investigate heat transfer in a porous domain having multiple channels.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 12 December 2018

Irfan Anjum Badruddin

The purpose of this paper is to investigate the heat transfer in an arbitrary cavity filled with porous medium. The geometry of the cavity is such that an isothermal heating…

Abstract

Purpose

The purpose of this paper is to investigate the heat transfer in an arbitrary cavity filled with porous medium. The geometry of the cavity is such that an isothermal heating source is placed centrally at the bottom of the cavity. The height and width of the heating source is varied to analyses its effect on the heat transfer characteristics. The investigation is carried out for three different cases of outer boundary conditions such as two outside vertical walls being maintained at cold temperature To, two vertical and top horizontal surface being heated to. To and the third case with top surface kept at To but other surfaces being adiabatic.

Design/methodology/approach

Finite element method is used to solve the governing equations.

Findings

It is observed that the cavity exhibits unique heat transfer behavior as compared to regular cavity. The cases of boundary conditions are found to affect the heat transfer rate in the porous cavity.

Originality/value

This is original work representing the heat transfer in irregular porous cavity with various boundary conditions. This work is neither being published nor under review in any other journal.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 19 December 2018

Ameer Ahamad Nandalur, Sarfaraz Kamangar and Irfan Anjum Badruddin

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…

Abstract

Purpose

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, Tc. 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.

Design/methodology/approach

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.

Findings

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

Originality/value

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

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Open Access
Article
Publication date: 1 July 2021

Sarfaraz Kamangar, N. Ameer Ahamad, N. Nik-Ghazali, Ali E. Anqi, Ali Algahtani, C. Ahamed Saleel, Syed Javed, Vineet Tirth and T.M. Yunus Khan

Coronary artery disease (CAD) is reported as one of the most common sources of death all over the world. The presence of stenosis (plaque) in the coronary arteries results in the…

Abstract

Purpose

Coronary artery disease (CAD) is reported as one of the most common sources of death all over the world. The presence of stenosis (plaque) in the coronary arteries results in the restriction of blood supply, leading to myocardial infarction. The current study investigates the influence of multi stenosis on hemodynamic properties in a patient-specific left coronary artery.

Design/methodology/approach

A three-dimensional model of the patient-specific left coronary artery was reconstructed based on computed tomography (CT) scan images using MIMICS-20 software. The diseased model of the left coronary artery was investigated, having the narrowing of 90% and 70% of area stenosis (AS) at the left anterior descending (LAD) and left circumflex (LCX), respectively.

Findings

The results indicate that the upstream region of stenosis experiences very high pressure for 90% AS during the systolic period of the cardiac cycle. The pressure drops maximum as the flow travels into the stenotic zone, and the high flow velocities were observed across the 90% AS. The higher wall shear stresses occur at the stenosis region, and it increases with the increase in the flow rate. It is found that the maximum wall shear stress across 90% AS is at the highest risk for rupture. A recirculation region immediately after the stenosis results in the further development of stenosis.

Originality/value

The current study provides evidence that there is a strong effect of multi-stenosis on the blood flow in the left coronary artery.

Details

Frontiers in Engineering and Built Environment, vol. 1 no. 1
Type: Research Article
ISSN: 2634-2499

Keywords

Article
Publication date: 5 March 2018

Yukichika Kawata, Sheila Nu Nu Htay and Ahmed Syed Salman

This study aims to examine whether citizens of non-Muslim countries accept products with a “halal” logo. In the era of globalization, one of the most crucial issues for Muslim…

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Abstract

Purpose

This study aims to examine whether citizens of non-Muslim countries accept products with a “halal” logo. In the era of globalization, one of the most crucial issues for Muslim travelers is reliable halal foods when visiting non-Muslim countries. If people in non-Muslim countries accept imported products containing halal certification logos, and such products are readily available in shops, this issue could be substantially improved.

Design/methodology/approach

Malaysia and Japan were selected as Muslim and non-Muslim countries, respectively, to conduct a choice experiment (CE) for 656 non-Muslim subjects, and estimated willingness to pay (WTP) for mineral water with and without the halal logo. A random parameter logit model was used for estimation.

Findings

The difference between the WTP for mineral water with and without the halal logo was ¥5; however, the associated coefficient is not statistically significant. This implies that the halal logo has no impact on non-Muslim subjects’ purchasing behavior. From this, we can infer that the halal products with certification logo would be accepted in Japanese shops, which may foster foreign Muslim visits.

Research limitations/implications

As the results are based on a couple of countries (Malaysia and Japan) and only one product (mineral water), further investigation using other products in different countries would be necessary. However, as suggested in the main text, the results enjoy a degree of generalizability.

Originality/value

The results of this study support the possibility of circulating halal products in non-Muslim countries and thus promoting Muslim travel abroad. No such study has examined this issue using CE.

Details

Journal of Islamic Marketing, vol. 9 no. 1
Type: Research Article
ISSN: 1759-0833

Keywords

Article
Publication date: 18 July 2019

Zahid Ahmed, Sohail Nadeem, Salman Saleem and Rahmat Ellahi

The purpose of this paper is to present a novel model on the unsteady MHD flow of heat transfer in carbon nanotubes with variable viscosity over a shrinking surface.

Abstract

Purpose

The purpose of this paper is to present a novel model on the unsteady MHD flow of heat transfer in carbon nanotubes with variable viscosity over a shrinking surface.

Design/methodology/approach

The temperature-dependent viscosity makes the proposed model non-linear and coupled. Consequently, the resulting non-linear partial differential equations are first reformed into set of ordinary differential equations through appropriate transformations and boundary layer approximation and are then solved numerically by the Keller box method.

Findings

Graphical and numerical results are executed keeping temperature-dependent viscosity of nanofluid. It is noted that, for diverse critical points, it is found that at one side of these critical values, multiple solutions exist; on the other side, no solution exists. A comparison is also computed for the special case of existing study. The temperature and pressure profiles are also plotted for various effective parameters.

Originality/value

The work is original.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 9 August 2021

Vishnudas Alias Vipul Luvu Chodankar, Aswatha and K.N. Seetharamu

The purpose of this paper is to attain higher effectiveness with an introduction of Joule–Thomson effect on a three-fluid heat exchanger with two communications. It also gives a…

Abstract

Purpose

The purpose of this paper is to attain higher effectiveness with an introduction of Joule–Thomson effect on a three-fluid heat exchanger with two communications. It also gives a range of parameter values that have to be maintained for achieving effectiveness above 0.85. Attaining effectiveness above 0.85 is very important for the heat exchanger to perform the liquefaction of hot fluid.

Design/methodology/approach

The analysis is conducted using Galerkin’s method, a finite element approach.

Findings

This investigation determines crucial values for the cryogenic heat exchanger to achieve effectiveness above 0.85. The important findings are as follows: effectiveness above 0.85 is attained if the heat exchanger size is within the range of 8–10; ratio of heat flow resistance between intermediate and hot stream to heat flow resistance between cold and hot stream should be maintained between 1 and 10; the intermediate fluid temperature should be maintained between 0 and 0.2; the ratio of thermal capacity of the hot fluid relative to a cold fluid should be maintained between 1.25 and 1.42; and the ratio of thermal capacity of the hot fluid relative to an intermediate fluid should be maintained between 2 and 2.5.

Research limitations/implications

The investigation has presented a finding for improving the effectiveness of the cryogenic heat exchanger. Higher the Joule–Thomson pressure drop effect, more is the drop in temperature of the fluid resulting in additional cooling or lowering of the fluid temperature. The practical implementation is also explained, i.e. to achieve practically the Joule–Thomson pressure drop in a cryogenic heat exchanger.

Originality/value

To the best of the authors’ knowledge, no investigations were carried out previously on Joule–Thomson investigation on a three-fluid heat exchanger with two communications, for different values of Joule–Thomson pressure drop.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 5 May 2021

Evangelos Psomas, Christina Dimitrantzou and Fotios Vouzas

The present study focuses on the cost of quality (CoQ) based on which organizations can evaluate their quality-related activities in economic terms. The purpose of the study is to…

Abstract

Purpose

The present study focuses on the cost of quality (CoQ) based on which organizations can evaluate their quality-related activities in economic terms. The purpose of the study is to identify the CoQ practical implications as well as to group them into logical themes.

Design/methodology/approach

A systematic literature review (SLR) was conducted based on well-known academic publishers, such as Emerald Insight, Elsevier/ScienceDirect, SpringerLink, Taylor & Francis, Wiley and Scopus. Sixty-seven peer-reviewed journal articles in the field of CoQ were collected, which were published between 2010 and 2019. The “affinity diagram” was applied to group the practical implications identified into logical themes.

Findings

A plethora of CoQ practical implications were identified and grouped into the following meaningful themes: benefits of CoQ measurement, effects of CoQ, business sectors measuring CoQ, factors influencing CoQ measurement, CoQ elements, future research in CoQ and the role of government.

Research limitations/implications

The limited number of the publishers and keywords used to search for the articles of interest, as well as the subjectivity of grouping the large number of the practical implications into themes are the main limitations of the present study. These limitations constitute the basis upon which future literature review studies can be designed.

Practical implications

The present study by presenting analytically and in summary (through the themes revealed) the CoQ practical implications, provides all the respective available literature in a single study for the benefit of practitioners and academics. Thus, clear and straightforward guidelines are given to practitioners with regard to CoQ issues and academics with regard to research topics of high interest.

Originality/value

No previous SLR study focusing on analyzing the practical implications of CoQ has been published so far.

Details

International Journal of Productivity and Performance Management, vol. 71 no. 8
Type: Research Article
ISSN: 1741-0401

Keywords

1 – 10 of 511