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Article
Publication date: 26 July 2024

U.S. Mahabaleshwar, S.M. Sachin, A.B. Vishalakshi, Gabriella Bognar and Bengt Ake Sunden

The purpose of this paper is to study the two-dimensional micropolar fluid flow with conjugate heat transfer and mass transpiration. The considered nanofluid has graphene…

46

Abstract

Purpose

The purpose of this paper is to study the two-dimensional micropolar fluid flow with conjugate heat transfer and mass transpiration. The considered nanofluid has graphene nanoparticles.

Design/methodology/approach

Governing nonlinear partial differential equations are converted to nonlinear ordinary differential equations by similarity transformation. Then, to analyze the flow, the authors derive the dual solutions to the flow problem. Biot number and radiation effect are included in the energy equation. The momentum equation was solved by using boundary conditions, and the temperature equation solved by using hypergeometric series solutions. Nusselt numbers and skin friction coefficients are calculated as functions of the Reynolds number. Further, the problem is governed by other parameters, namely, the magnetic parameter, radiation parameter, Prandtl number and mass transpiration. Graphene nanofluids have shown promising thermal conductivity enhancements due to the high thermal conductivity of graphene and have a wide range of applications affecting the thermal boundary layer and serve as coolants and thermal management systems in electronics or as heat transfer fluids in various industrial processes.

Findings

Results show that increasing the magnetic field decreases the momentum and increases thermal radiation. The heat source/sink parameter increases the thermal boundary layer. Increasing the volume fraction decreases the velocity profile and increases the temperature. Increasing the Eringen parameter increases the momentum of the fluid flow. Applications are found in the extrusion of polymer sheets, films and sheets, the manufacturing of plastic wires, the fabrication of fibers and the growth of crystals, among others. Heat sources/sinks are commonly used in electronic devices to transfer the heat generated by high-power semiconductor devices such as power transistors and optoelectronics such as lasers and light-emitting diodes to a fluid medium, thermal radiation on the fluid flow used in spectroscopy to study the properties of materials and also used in thermal imaging to capture and display the infrared radiation emitted by objects.

Originality/value

Micropolar fluid flow across stretching/shrinking surfaces is examined. Biot number and radiation effects are included in the energy equation. An increase in the volume fraction decreases the momentum boundary layer thickness. Nusselt numbers and skin friction coefficients are presented versus Reynolds numbers. A dual solution is obtained for a shrinking surface.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 9
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 26 March 2024

U.S. Mahabaleshwar, Mahesh Rudraiah, Huang Huang and Bengt Ake Sunden

The purpose of this study is to analyze the impact of inclined magnetohydrodynamics (MHD) and thermal radiation on the flow of a ternary micropolar nanofluid on a sheet that is…

107

Abstract

Purpose

The purpose of this study is to analyze the impact of inclined magnetohydrodynamics (MHD) and thermal radiation on the flow of a ternary micropolar nanofluid on a sheet that is expanding and contracting while applying mass transpiration and velocity slip conditions to the flow. The nanofluid, which is composed of Au, Ag and Cu nanoparticles dispersed in water as the base fluid, possesses critical properties for increasing the heat transfer rate and is frequently used in manufacturing and industrial establishments.

Design/methodology/approach

The set of governing nonlinear partial differential equations is transformed into a set of nonlinear ordinary differential equations. The outcome of this differential equation is solved and obtained the closed-form solution and energy equation in the form of hypergeometric functions.

Findings

The velocity, micro-rotation and temperature field are investigated versus a parametric variation. The physical domains of mass suction or injection and micropolar characteristics play an important role in specifying the presence, singleness and multiplanes of exact solutions. In addition, many nondimensional characteristics of the profiles of temperature, angular velocity and velocity profiles are graphically shown with substantial consequences. Furthermore, adding nanoparticles increases the heat transfer rate of the fluid used in manufacturing and industrial establishments. The current findings may be used for better oil recovery procedures, smart materials such as magnetorheological fluids, targeted medicine administration and increased heat transmission. Concerning environmental cleanup, nanomaterial fabrication and biomedical devices, demonstrate their potential influence in a variety of disciplines.

Originality/value

The originality of this paper is to analyze the impact of inclined MHD at an angle with the ternary nanofluid on a micropolar fluid over an expanding and contracting sheet with thermal radiation effect.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 14 November 2024

B. Jaismitha and J. Sasikumar

This study aims to investigate the heat and mass transfer characteristics of a temperature-sensitive ternary nanofluid in a porous medium with magnetic field and the Soret–Dufour…

28

Abstract

Purpose

This study aims to investigate the heat and mass transfer characteristics of a temperature-sensitive ternary nanofluid in a porous medium with magnetic field and the Soret–Dufour effect through a tapered asymmetric channel. The ternary nanofluid consists of Boron Nitride Nanotubes (BNNT), silver (Ag) and copper (Cu) nanoparticles, with a focus on understanding the thermal behaviour and performance across mono, hybrid and tri-hybrid nanofluids. This paper also examines the thermal behaviour of MHD oscillatory nanofluid flow and carries out an uncertainty analysis of the model using the Taguchi method.

Design/methodology/approach

The governing equations for this system are transformed into coupled linear partial differential equations using non-similarity transformations and solved numerically with the Crank–Nicolson scheme. The impact of temperature sensitivity at three distinct temperatures (5°C, 20°C and 60°C) is incorporated to analyse variations in viscosity and Prandtl number. The study also examines the combined effects of Soret–Dufour numbers and thermal radiation on heat and mass transfer within the nanofluid.

Findings

The results demonstrate that the inclusion of BNNT, Ag and Cu nanoparticles significantly enhances heat and mass transfer rate, with copper nanoparticles showing superior performance in terms of skin friction and heat transfer rates. The Soret and Dufour effects play critical roles in modulating heat and mass diffusion within tri-hybrid nanofluids. The study reveals that temperature sensitivity alters heat and mass transfer characteristics depending on the temperature range, with pronounced variations at elevated temperatures. The influence of thermal radiation and the Peclet number is found to significantly impact temperature distribution and overall heat transfer performance within the asymmetric channel.

Originality/value

To the best of the authors’ knowledge, this study is the first to analyse the heat and mass diffusion in a ternary nanofluid composed of BNNT, Ag and Cu nanoparticles, considering porous media, oscillatory flow and thermal radiation within a tapered asymmetric channel. The research extends to a novel examination of temperature sensitivity in mono, hybrid and tri-hybrid nanofluids at varying temperature gradients. Furthermore, a comparative analysis of skin friction and heat transfer rates between copper, alumina and ferro composites is presented for optimising the nanofluid performance.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 35 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 16 April 2024

Latifah Falah Alharbi, Umair Khan, Aurang Zaib and Anuar Ishak

A novel type of heat transfer fluid known as hybrid nanofluids is used to improve the efficiency of heat exchangers. It is observed from literature evidence that hybrid nanofluids…

69

Abstract

Purpose

A novel type of heat transfer fluid known as hybrid nanofluids is used to improve the efficiency of heat exchangers. It is observed from literature evidence that hybrid nanofluids outperform single nanofluids in terms of thermal performance. This study aims to address the stagnation point flow induced by Williamson hybrid nanofluids across a vertical plate. This fluid is drenched under the influence of mixed convection in a Darcy–Forchheimer porous medium with heat source/sink and entropy generation.

Design/methodology/approach

By applying the proper similarity transformation, the partial differential equations that represent the leading model of the flow problem are reduced to ordinary differential equations. For the boundary value problem of the fourth-order code (bvp4c), a built-in MATLAB finite difference code is used to tackle the flow problem and carry out the dual numerical solutions.

Findings

The shear stress decreases, but the rate of heat transfer increases because of their greater influence on the permeability parameter and Weissenberg number for both solutions. The ability of hybrid nanofluids to strengthen heat transfer with the incorporation of a porous medium is demonstrated in this study.

Practical implications

The findings may be highly beneficial in raising the energy efficiency of thermal systems.

Originality/value

The originality of the research lies in the investigation of the Darcy–Forchheimer stagnation point flow of a Williamson hybrid nanofluid across a vertical plate, considering buoyancy forces, which introduces another layer of complexity to the flow problem. This aspect has not been extensively studied before. The results are verified and offer a very favorable balance with the acknowledged papers.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 16 August 2022

Najiyah Safwa Khashi’ie, Iskandar Waini, Norihan Md Arifin and Ioan Pop

This paper aims to analyse numerically the unsteady stagnation-point flow of Cu-Al2O3/H2O hybrid nanofluid towards a radially shrinking Riga surface with thermal radiation.

173

Abstract

Purpose

This paper aims to analyse numerically the unsteady stagnation-point flow of Cu-Al2O3/H2O hybrid nanofluid towards a radially shrinking Riga surface with thermal radiation.

Design/methodology/approach

The governing partial differential equations are transformed into a set of ordinary (similar) differential equations by applying appropriate transformations. The numerical computation of these equations including the stability analysis is conducted using the bvp4c solver.

Findings

Two solutions are possible within the allocated interval: shrinking parameter, unsteadiness decelerating parameter, electro-magneto-hydrodynamics (EMHD) parameter, nanoparticles volumetric concentration, radiation parameter and width parameter, whereas the stability analysis certifies that the first (upper branch) solution, which fulfills the boundary conditions is the physical/real solution. The EMHD parameter generated from the application of Riga plate enhances the skin friction coefficient as well as the heat transfer process. The width parameter d is also one of the factors in the deterioration of the skin friction coefficient and heat transfer rate. It is crucial to control the width parameter of the magnets and electrodes to obtain the desired outcome. The radiation parameter is not affecting the boundary layer separation because the critical values are unchanged. However, the addition of radiation and unsteadiness decelerating parameters boosts the thermal rate.

Originality/value

The results are novel and contribute to the discovery of the flow and thermal performance of the hybrid nanofluid subjected to a radially shrinking Riga plate. Besides, this work is beneficial to the other researchers and general audience from industries regarding the factors which contribute to the thermal enhancement of the working fluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 5 January 2015

M. Ramzan, M. Farooq, M. S. Alhothuali, H. M. Malaikah, W. Cui and T. Hayat

– The purpose of this paper is to analyze the boundary layer flow of an Oldroyd-B fluid with Newtonian heating.

197

Abstract

Purpose

The purpose of this paper is to analyze the boundary layer flow of an Oldroyd-B fluid with Newtonian heating.

Design/methodology/approach

Series solutions are found by homotopy analysis method.

Findings

Temperature profile increases with an increase in conjugate parameter. Increase in parameter β and Prandtl number Pr decreases the temperature profile.

Originality/value

This work does not currently exist in the literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 25 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 18 January 2022

T. Longvah, Anitha Chauhan, Sreedhar Mudavath, Bhaskar Varanasi and Neeraja CN

Rice landraces are essential for supplying beneficial traits for developing improved rice varieties with better nutritional quality. Nevertheless, in a yield-driven environment…

104

Abstract

Purpose

Rice landraces are essential for supplying beneficial traits for developing improved rice varieties with better nutritional quality. Nevertheless, in a yield-driven environment, grain nutritional quality has been ignored especially that of rice landraces. Given this, the purpose of this study is to evaluate the content and nutritional variability of rice landraces from Manipur.

Design/methodology/approach

Thirty-three most popular rice landraces were collected as dry paddy samples from Manipur and transported to the National Institute of Nutrition, Hyderabad, by air. All the paddy samples were processed and analyzed for 35 nutrient parameters using standard methodologies.

Findings

The mean nutrient content of Nagaland brown rice was: protein 7.5 ± 0.8, fat 3.0 ± 0.3, TDF 5.5 ± 0.4 and ash 1.2 ± 0.2 g/100g. The range of water soluble-vitamin content in mg/100g, was 0.1–0.43 for Thiamine and for Niacin 2.1–3.5, while the content in µg/100g was 40–64 for Riboflavin, 0.5–3.9 for Pantothenic acid and 20–118 for Pyridoxine. A relatively large coefficient of variation was observed for iron (25%), manganese (28%), copper (32%), calcium (13%) and phosphorus (11%). Manipur rice landraces have significantly higher total dietary fiber and lower phytate contents than modern varieties. Milling led to steep losses of nutrients, and limiting to 5% milling substantially improves nutrient retention in milled rice.

Research limitations/implications

Future nutrition interventions should use rice with superior nutrient quality to improve nutrient intakes. Manipur rice landraces conserved over generations can broaden the genetic base of breeding stocks especially in the face of climate change.

Originality/value

The paper presents comprehensive nutritional data of 33 rice landraces from the state of Manipur, India. The results indicate large nutrient variability even within these 33 rice landraces with important traits such as high total dietary fiber and low phytate contents. The study highlights the importance of conserving the existing rich genetic material of Manipur rice landraces to develop varieties that combine higher yields with stress tolerance and superior grain nutritional value to improve the food and nutrient security.

Details

Nutrition & Food Science , vol. 52 no. 7
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 3 April 2017

Rohana Abdul Hamid, Roslinda Nazar and Ioan Pop

The purpose of this paper is to numerically study the boundary layer problem for the case of two-dimensional flow of dusty fluid over a shrinking surface in the presence of the…

175

Abstract

Purpose

The purpose of this paper is to numerically study the boundary layer problem for the case of two-dimensional flow of dusty fluid over a shrinking surface in the presence of the fluid suction at the surface.

Design/methodology/approach

The governing equations of the problem are reduced to the system of ordinary differential equations using the similarity transformation and then solved using the bvp4c method in the Matlab software.

Findings

The effects of the drag coefficient parameter L, the fluid–particle interaction parameter δ, the suction parameter s and the particle loading parameter ω on the flow of the permeable shrinking sheet are investigated. It is found that the aforementioned parameters have different effects in the shrinking sheet flow. This study has also succeeded in discovering the second solution, and through the stability analysis, it is suggested that the solution is unstable and not physically realizable in practice.

Practical implications

The current findings add to a growing body of literature on the boundary layer problem in the dusty fluid. The dusty fluid is significant in various practical applications such as in the transporting suspended powdered materials through pipes, propulsion and combustion in rockets, the flow of blood in arteries, wastewater treatment and as corrosive particles in engine oil flow.

Originality/value

Even though the dusty fluid problem has been extensively studied in the flow of the stretching sheet, limited findings can be found over a shrinking flow. In fact, this is the first study to discover the second solution in the dusty fluid problem.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 4
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 2 October 2017

Herianus Justhianus D. Lalel, I. Nyoman Widiarta Mahayasa, Zulianatul Hidayah and Kartiwan Kartiwan

The purposes of this paper are to determine the nutritional composition of the pulp and its antioxidant activity; study the effect of drying and storage on the nutritional…

183

Abstract

Purpose

The purposes of this paper are to determine the nutritional composition of the pulp and its antioxidant activity; study the effect of drying and storage on the nutritional composition and antioxidant of the pulp; investigate the effect of de-bittering using fermentative microbes, sodium carbonate and polyethylene glycol (PEG) on antioxidant of the pulp, and to study the shelf-life and sensory evaluation of de-bittered pulp products.

Design/methodology/approach

The ripe fruits of palmyra (Borassus flabellifer L) were collected around Kupang city, Indonesia. The pulp was extracted with different techniques. The fresh pulp was directly analyzed for its nutritional and antioxidant properties. The rest of the pulp was de-bittered, dried and used for further treatments and products development. The de-bittered pulp was used to make chips, stick cracker, and jelly sweet. Fresh products were sensory evaluated by 30 semi-trained panelists. For shelf-life analysis, products were wrapped and/or packed with different thickness of food grade plastic, plastic-alumina foil, or mica stopples and kept at different temperatures (30, 40 and 50oC) for one month.

Findings

The fresh pulp contains carotenoids (609.10 mg per kg of pulp), vitamin C (461.40 mg per kg of pulp), polyphenols (270 mg per kg of pulp) and anthocyanin (53.90 mg per kg of pulp). Free radical scavenging activity of the dried pulp (water content of 11.60 percent) was 93.4 percent. Several techniques including fermentation, sodium carbonate, and PEG treatment have been successfully developed to reduce the bitterness of the pulp without significantly reducing its antioxidant activities. Food products (chips, stick cracker, and jelly sweet) have then been developed and have got positive response from panelist.

Research limitations/implications

Pulp of fruit is a potential source of antioxidants, i.e. carotenoids (pro vitamin A), vitamin C, and polyphenols. The pulp potentially can be used in fresh and dried form for functional food. The bitterness of the pulp can be significantly reduced using fermentation, sodium carbonate or PEG treatment. The pulp can be utilized for producing chips, crackers, and semi moist food products.

Practical implications

First, pulp of the palmyrah fruit can be easily extracted using water. Second, the bitterness of the pulp can be reduced by using traditional fermentation starter. Third, many type of food products can be developed using the palmyrah pulp.

Social implications

This effort offers opportunity for farmers to optimize the use of palmyrah pulp for functional food. It will provide new jobs and increase the income of farmer at East Nusa Tenggara Province.

Originality/value

The study has revealed that pulp of palmyrah fruit is a source of antioxidants: carotenoids (pro vitamin A), vitamin C, and polyphenols. The pulp potentially can be used in fresh and dried form for functional food. The bitterness of the pulp can be significantly reduced using fermentation, sodium carbonate, and PEG. The pulp can be utilized for producing chips, crackers, and semi moist food products.

Details

British Food Journal, vol. 119 no. 10
Type: Research Article
ISSN: 0007-070X

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