Taher Armaghani¹, Lioua Kolsi², Najiyah Safwa Khashi’ie^3,*, Ahmed Muhammed Rashad⁴, Muhammed Ahmed Mansour⁵, Taha Salah⁶, Aboulbaba Eladeb⁷

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.3, pp. 2225-2251, 2024, DOI:10.32604/cmes.2024.056676 - 31 October 2024

Abstract In this paper, the unsteady magnetohydrodynamic (MHD)-radiation-natural convection of a hybrid nanofluid within a U-shaped wavy porous cavity is investigated. This problem has relevant applications in optimizing thermal management systems in electronic devices, solar energy collectors, and other industrial applications where efficient heat transfer is very important. The study is based on the application of a numerical approach using the Finite Difference Method (FDM) for the resolution of the governing equations, which incorporates the Rosseland approximation for thermal radiation and the Darcy-Brinkman-Forchheimer model for porous media. It was found that the increase of Hartmann number… More >

M. Sridevi¹, B. Shankar Goud², Ali Hassan^3,4,*, D. Mahendar⁵

Frontiers in Heat and Mass Transfer, Vol.22, No.3, pp. 939-953, 2024, DOI:10.32604/fhmt.2024.050929 - 11 July 2024

Abstract This study intends to evaluate the influence of temperature stratification on an unsteady fluid flow past an accelerated vertical plate in the existence of viscous dissipation. It is assumed that the medium under study is a grey, non-scattered fluid that both fascinates and transmits radiation. The leading equations are discretized using the finite difference method (FDM). Using MATLAB software, the impacts of flow factors on flow fields are revealed with particular examples in graphs and a table. In this regard, FDM results show that the velocity and temperature gradients increase with an increase of Eckert More >

T. Aghalya, R. Tamizharasi^*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 431-460, 2024, DOI:10.32604/cmes.2024.046635 - 16 April 2024

Abstract In this study, the characteristics of heat transfer on an unsteady magnetohydrodynamic (MHD) Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated. The flow was driven by the combined effects of the magnetic field, heat radiation, heat source/sink and chemical reaction. Copper oxide () and titanium oxide () are acknowledged as nanoparticle materials. The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions. Graphical representations are provided to analyze how changes in physical parameters, such as the magnetic field, heat radiation, heat source/sink and chemical… More >

Matthew R. Coburn¹, Charlie Young², Chris Smith², Graham Schultz², Miguel Robayo³, Zheng-Tong Xie^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 547-562, 2024, DOI:10.32604/fdmp.2023.028601 - 12 January 2024

Abstract A prototype cleanroom for hazardous testing and handling of satellites prior to launcher encapsulation, satisfying the ISO8 standard has been designed and analyzed in terms of performances. Unsteady Reynolds Averaged Navier-Stokes (URANS) models have been used to study the related flow field and particulate matter (PM) dispersion. The outcomes of the URANS models have been validated through comparison with equivalent large-eddy simulations. Special attention has been paid to the location and shape of the air intakes and their orientation in space, in order to balance the PM convection and diffusion inside the cleanroom. Forming a More >

Junying Wei^*, Gang Li, Chenrui Zhang, Wenwen Chang, Jidai Wang

Frontiers in Heat and Mass Transfer, Vol.21, pp. 199-214, 2023, DOI:10.32604/fhmt.2023.041793 - 30 November 2023

Abstract To study the complex internal flow field variation and output characteristics of a variable base radius scroll expander, this paper uses dynamic mesh techniques and computational fluid dynamics (CFD) methods to perform transient numerical simulations of a variable base radius scroll expander. Analysis of the flow field in the working cavity of a variable base radius scroll expander at different spindle angles and the effect of different profiles, speeds and pressures on the output characteristics of the scroll expander. The results of the study show that due to the periodic blocking of the inlet by… More >

Xinyu Zhao^1,2,*, Mofeng Li², Kai Yan², Li Yin³

Energy Engineering, Vol.120, No.12, pp. 2933-2949, 2023, DOI:10.32604/ee.2023.041580 - 29 November 2023

Abstract This study presents an avant-garde approach for predicting and optimizing production in tight reservoirs, employing a dual-medium unsteady seepage model specifically fashioned for volumetrically fractured horizontal wells. Traditional models often fail to fully capture the complex dynamics associated with these unconventional reservoirs. In a significant departure from these models, our approach incorporates an initiation pressure gradient and a discrete fracture seepage network, providing a more realistic representation of the seepage process. The model also integrates an enhanced fluid-solid interaction, which allows for a more comprehensive understanding of the fluid-structure interactions in the reservoir. This is… More >

D. Santhi Kumari^a,* , Venkata Subrahmanyam Sajja^a , P. M. Kishore^b,†

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-11, 2023, DOI:10.5098/hmt.20.5

Abstract The aim of present study is an influence of viscous dissipation and heat source on an unsteady MHD mixed convective, fluid flow past an impulsively started oscillating plate embedded in a porous medium in presence of magnetic field, heat and mass transfer. The modeling equations are converted to dimensionless equations then solved through Galerkin finite element method and discussed in the flow distributions with the help of MATLAB. Numerical results for the velocity, temperature and concentration distributions as well as the skin-friction coefficient, Nusselt number and Sherwood number are discussed in detail and displayed graphically More >

Toufik Sahabi^1,*, Smain Balaska²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 977-990, 2023, DOI:10.32604/fdmp.2022.022059 - 02 November 2022

Abstract The heat transfer equation is used to determine the heat flow by conduction through a composite material along the real axis. An analytical dimensionless analysis is implemented in the framework of a separation of variables method (SVM). This approach leads to an Eigenvalues problem that is solved by the Newton’s method. Two types of dynamics are found: An unsteady condition (in the form of jumps or drops in temperatures depending on the considered case), and a permanent equilibrium (tending to the ambient temperature). The validity and effectiveness of the proposed approach for any number of More > Graphic Abstract

Muhammad A. Sadiq^1,2,*, Nadeem Abbas³, Haitham M. S. Bahaidarah⁴, Mohammad Amjad⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 471-486, 2023, DOI:10.32604/fdmp.2022.021133 - 29 August 2022

Abstract We present the results of an investigation into the behavior of the unsteady flow of a Casson Micropolar nanofluid over a shrinking/stretching curved surface, together with a heat transfer analysis of the same problem. The body force acting perpendicular to the surface wall is in charge of regulating the fluid flow rate. Curvilinear coordinates are used to account for the considered curved geometry and a set of balance equations for mass, momentum, energy and concentration is obtained accordingly. These are turned into ordinary differential equations using a similarity transformation. We show that these equations have More >

Bamdeb Dey^a,† , Bhrigu Kumar Kalita^b, Rita Choudhury^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-8, 2022, DOI:10.5098/hmt.18.32

Abstract In this paper, we attempt to analyze the effects of radiation and chemical reactions on laminar boundary layer flow of an electrically conducting unsteady viscoelastic incompressible fluid flow along a vertical semi-infinite plate passing through porous channel. The coupled nonlinear partial differential equations for energy, momentum, and mass diffusions are solved analytically with the use of perturbation technique. Moreover, the analytical expressions for fluid velocity, temperature, and concentration distributions are obtained and interpreted using the software MATLAB. The enhancement of velocity is prominent with the growth of G_r, G_m, N_r and K_r but a reverse pattern is More >