Noureddine Abouricha^1,*, Chouaib Ennawaoui^1,2, Mustapha El Alami³

Frontiers in Heat and Mass Transfer, Vol.21, pp. 523-537, 2023, DOI:10.32604/fhmt.2023.045914

Abstract This work presents a simulation of the phenomena of natural convection in an enclosure with a variable heating regime by the lattice Boltzmann method (LBM). We consider a square enclosure of side H filled with air (Pr = 0.71) and heated from below, with a hot portion of length L = 0.8 H, by imposing a sinusoidal temperature. The unheated segments of the bottom wall are treated as adiabatic, and one of the vertical walls features a cold region, while the remaining walls remain adiabatic. The outcomes of the two-dimensional (2D) problem are depicted through isotherms, streamlines, the temperature evolution… More >

B. Rushi Kumar^* , T. Sravan Kumar, A .G Vijaya Kumar

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-9, 2015, DOI:10.5098/hmt.6.12

Abstract The objective of this study is to investigated thermal diffusion and radiation effects on unsteady free convection chemically reacting fluid flow past an accelerated infinite inclined plate with variable temperature and mass diffusion under the influence of uniform transverse magnetic field when the magnetic lines of force are fixed relative to the fluid or to the plate studied in two cases, (i) when magnetic field fixed relative to the fluid (K=0), (ii) and the magnetic field fixed relative to the plate (K=1) have been considered. A general exact solution of the dimensionless governing partial differential equation is obtained by the… More >

M. Y. Abdollahzadeh Jamalabadi^*

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-13, 2015, DOI:10.5098/hmt.6.7

Abstract An analytical study of entropy generation in steady boundary layer flow, heat and mass transfer characteristic of 2D convective flow of a micro polar fluid over a stretching sheet embedded through a highly absorbing medium is performed. The governing equations are continuity, momentum boundary layer, micro rotation, and energy takes into account of Rosseland approximation for thermal radiation sources are solved analytically. The governing system of partial differential equations is first transformed into a system of non-linear ordinary differential equations using similarity transformation. The transformed equations are non-linear coupled differential equations which are then linearized by quasi-linearization method and solved… More >

R.R. Kairi^a, Ch. RamReddy^b,*

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-7, 2015, DOI:10.5098/hmt.6.6

Abstract In this paper, we investigated the influence of melting on mixed convection heat and mass transfer from the vertical flat plate in a non-Newtonian nanofluid saturated porous medium. The wall and the ambient medium are maintained at constant, but different, levels of temperature and concentration. The Ostwald–de Waele power-law model is used to characterize the non-Newtonian nanofluid behavior. A similarity solution for the transformed governing equations is obtained. The numerical computation is carried out for various values of the non-dimensional physical parameters. The variation of temperature, concentration, heat and mass transfer coefficients with the power-law index, mixed convection parameter, melting… More >

Mitiku Daba^*, P. Devaraj, S. V. Subhashini

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-6, 2015, DOI:10.5098/hmt.6.3

Abstract In the present study, we investigated a problem of steady laminar mixed convection flow over a vertically stretching sheet with partial slip under convective surface boundary condition. The governing partial differential equations of the boundary layer flow are reduced into a set of nonlinear ordinary differential equations using a suitable similarity transformations. The system of non linear ordinary differential equations are solved by the Keller box method. Velocity, temperature and heat transfer rate are analyzed by considering the important parameters: Prandtl number Pr, convective parameter ε, slip parameter K and mixed convection parameter λ on the fluid flow and the… More >

Manoj Kr. Triveni^*, Dipak Sen, RajSekhar Panua

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-6, 2015, DOI:10.5098/hmt.6.2

Abstract A numerical investigation through laminar natural convection has been executed to illuminate the effect of curvature ratio in an arch enclosure filled with water. The left side wall of the cavity is maintained at a higher temperature than that of the right side wall while the other walls are kept insulated. The governing equations such as continuity, momentum and energy equation are solved by finite volume method. The effect of pertinent parameters such as curvature ratio (1≤ CR ≤ 1.5) and Rayleigh number (1×10⁴ ≤ Ra ≤ 1×10⁶) and) on heat transfer are calculated by commercial available computational fluid dynamics… More >

K. Kaladhar^a,∗, D. Srinivasacharya^b

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-10, 2016, DOI:10.5098/hmt.7.6

Abstract This present investigation carried out the effects of Hall current, Joule heating and the thermal diffusion on mixed convection flow of electrically conducting couple stress fluid in a vertical channel saturated with porous medium. The final system of ordinary differential equations are obtained from the governing non-linear partial differential equations by using the similarity transformations. Homotopy Analysis Method has been used to solve the non-linear system. The average residue errors of the HAM solutions are presented through graphs. The influence of the emerging parameters (Hall, Soret, magnetic and the couple stress parameters) on velocity, temperature and concentration profiles are presented… More >

Seyed Milad Mirabedin^*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-6, 2016, DOI:10.5098/hmt.7.17

Abstract This work focuses on numerical validation of natural convection heat transfer of TiO2-water nanofluids in a cylindrical container using COMSOL. The main aim of this study is to examine different available approaches to calculate effective thermal conductivity and compare them with experimental data available in the literature. Simulation results show that for considered mixture, average Nusselt number decreases by increasing Rayleigh number and particle volume fraction. It has been found that only one model was able to represent similar trends for given particle volume fractions, compared to experimental results. More >

Kun Zhang^*, Liang Bi Wang

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-7, 2016, DOI:10.5098/hmt.7.18

Abstract Detailed numerical analysis is presented for the effect of spaceship orbital transfer on solution convection during protein crystal growth under microgravity. The results show that the flow and mass transfer during protein crystal growth are unsteady in the process of orbital transfer. For the case of quasi-steady acceleration, the flow is so weak that the effect of flow on concentration field can be negligible. For the case of position adjustment, the convection is enhanced with protein crystal diameter d_c > 0.2 mm and slightly alters the purely diffusive concentration distribution under zero gravity condition. For the case of motor working,… More >

Vandana Bisht^*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-7, 2016, DOI:10.5098/hmt.7.19

Abstract In this paper the steady laminar magneto hydrodynamic (MHD) mixed convection boundary layer flow towards a vertical stretching sheet with variable fluid viscosity, radiation and in the presence of Dufour’s effect have been investigated. The governing partial differential equations are transformed into set of ordinary differential equations using similarity transformation, and then these equations have been solved numerically using Runge- Kutta method with shooting technique. Results shows that magnitude of skin friction coefficient decreases, while magnitude of heat transfer coefficient and mass transfer coefficient increases with decreasing values of viscosity variation parameter for the case of opposing flow. But in… More >