Throughflow Effect on Local and Large-scale Penetrative Convection in Superposed Air-porous Layer with Internal Heat Source Depending on Solid Fraction

Kolchanova, Ekaterina; Sagitov, Rafil

doi:10.1007/s12217-022-09971-2

Cited by 8 publications

(4 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The search results provide several studies that investigate the effect of air velocity on heat transfer in different contexts, such as natural convection in an air channel with a cavity [34], heat transfer in a rectangular tube [35], and plate-fin heat sinks under forced air convection [36]. Other studies explore the effect of air velocity on heat transfer in cyclone heat exchangers [37], the throughflow effect on local and large-scale penetrative convection [38], and convection air currents around a hot cylinder inside a triangular cavity [39].…”

Section: Introductionmentioning

confidence: 99%

Heat Convection in a Channel-Opened Cavity with Two Heated Sources and Baffle

Rashid,

Al-Gaheeshi,

Mohammed

et al. 2024

Energies

View full text Add to dashboard Cite

This study employs COMSOL software v 5.6 to investigate a novel approach to heat transfer via mixed convection in an open hollow structure with an unheated 90° baffle elbow. Two 20 W heat sources are strategically positioned on the cavity’s bottom and right-angled wall for this research. Notably, the orientation of the baffle perpendicular to the airflow is used to direct external, unrestricted flow into the square cavity. The research investigates a range of air velocities (0.1, 0.5, 1.0, and 1.5 m/s) and the intricate interaction between input air velocity, dual heated sources, and the presence of a right-angle baffle on critical thermodynamic variables, such as temperature distribution, isotherms, pressure variation, velocity profile, air density, and both local and mean Nusselt numbers. Validation of the applicable computational method is achieved by comparing it to two previous studies. Significant findings from numerical simulations indicate that the highest velocity profile is in the centre of the channel (2.3–2.68 m/s at an inflow velocity of 1.5 m/s), while the lowest profile is observed along the channel wall, with a notable disruption near the inlet caused by increased shear forces. The cavity neck temperature ranges from 380 to 640 K, with inflow air velocities varying from 0.1 to 1.5 m/s (Re is 812 to 12,182), respectively. In addition, the pressure fluctuates at the channel-cavity junction, decreasing steadily along the channel length and reaching a maximum at the intake, where the cavity neck pressure varies from 0.01 to 2.5 Pa with inflow air velocities changing from 0.1 to 1.5 m/s, respectively. The mean Nusselt number exhibits an upward trend as air velocity upon entry increases. The mean Nusselt number reaches up to 1500 when the entry air velocity reaches 1.5 m/s. Due to recirculation patterns, the presence of the 90° unheated baffle produces a remarkable cooling effect. The study establishes a direct correlation between input air velocity and internal temperature distribution, indicating that as air velocity increases, heat dissipation improves. This research advances our understanding of convective heat transfer phenomena in complex geometries and provides insights for optimising thermal management strategies for a variety of engineering applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Heat Convection in a Channel-Opened Cavity with Two Heated Sources and Baffle

Rashid,

Al-Gaheeshi,

Mohammed

et al. 2024

Energies

View full text Add to dashboard Cite

show abstract

“…Подобные два вида конвекции наблюдались также при течении трёхкомпонентной смеси в двухслойной пористой среде [18] и однокомпонентной жидкости в среде с тремя пористыми подслоями [19]. Можно привести также ряд работ по анализу возникновения тепловой конвекции на фоне продольного [20,21] и поперечного [22,23] вынужденных течений в слоях, которые заполнены пористой матрицей частично. В данной работе рассматривается двухслойная пористая система, через которую прокачивается бинарная жидкость вдоль границы раздела горизонтальных подслоёв.…”

Section: Introductionunclassified

Formation of convective roll patterns over a longitudinal throughflow in an active inhomogeneous porous medium with weak clogging

Колчанова,

Колчанов

2024

Comp. Contin. Mech.

Self Cite

View full text Add to dashboard Cite

The convective stability of a plane-parallel longitudinal throughflow in a system consisting of two porous sublayers with distinct permeability is studied taking into account the weak pore clogging effect and given a finite difference in concentration between the upper and lower boundaries of the system. A system of differential equations for convection is derived within the framework of the continuum approach and the nonlinear MIM model. A linear stability analysis of the basic longitudinal flow is carried out. The boundary value problem is solved using the numerical technique for constructing a fundamental system of solutions. The neutral stability curves of the basic flow with respect to the disturbances in the form of rolls with different wavelength are obtained. For the absence of pore clogging, the convective stability maps of the critical solutal Rayleigh-Darcy number versus the permeability ratio for the initial uncontaminated sublayers, as well as the plots of the critical disturbance frequency and wave number versus the permeability ratio for some values of the Peclet number, are constructed. It is shown that these results have symmetry with respect to the solution for equal initial permeability of sublayers. The clogging effect associated with the solute adsorption and desorption in a porous medium is studied in the two-layered systems with the values 0.1 and 10 of the ratio of initial permeabilities of the sublayers; convection localization occurs in distinct sublayers. It was found that clogging increases the stability of the longitudinal basic flow relative to solutal inhomogeneity and breaks the symmetry of solutions with respect to the case when the two-layered system is reduced to a single layer with the same filtration properties of the porous medium throughout its volume. The influence of sorption effects on the critical parameters of oscillatory convection is investigated by plotting the critical solutal Rayleigh-Darcy number, disturbance frequency and wave number against the adsorption coefficient at fixed values of the desorption coefficient. The isolines of the stream function are constructed to analyze convective flow patterns. It was established that there is a weak relationship between the typical size of local convective roll patterns and the clogging parameters. It is shown that the sorption processes, which can lead to clogging, have a significant impact on the velocity of convective rolls moving along the two-layered system at a slight variation in their sizes.

show abstract

“…Yih and Huang (2020) used the KBM to solve cross diffusion and internal heat generation effects on mixed convection of non-Newtonian fluids flow adjacent to a vertical VHF/VMF wedge in porous media: the entire regime. Kolchanova and Sagitov (2022) investigated throughflow effect on local and large-scale penetrative convection in superposed air-porous layer with internal heat source depending on solid fraction. Huang and Yih (2023) spread the research of Hsieh et al (1993b) to analyze numerically the internal heat generation and Soret-Dufour effects on heat and mass transfer in mixed convection flows of power-law fluids about a VHF/VMF plate in porous media: the entire regime.…”

Section: Introductionmentioning

confidence: 99%

Influence of Dufour/Soret and Space-Dependent Internal Heat Source on Combined Convection of Non-Newtonian Fluids Flow Past a Vertical Full Cone in Porous Media: The VHF/VMF Case

Yih,

Hsu

2024

Microgravity Sci. Technol.

View full text Add to dashboard Cite

This paper numerically analyzes the influence of Dufour/Soret and space-dependent internal heat source (exponential decaying form) on combined convection (entire regime) of non-Newtonian fluids (power-law model of Ostwald-de-Waele) flow past a vertical full cone in porous media with the boundary conditions of VHF/VMF case. The transformed governing equations (non-similar equations) are solved by Keller box method (KBM). Comparison with previously published work is very good. Numerical data for the dimensionless temperature profile, the dimensionless concentration profile, the local Nusselt number and the local Sherwood number are graphically and tabularly presented for the nine parameters: the buoyancy ratio N , the Lewis number Le, the Dufour parameter Df , the Soret parameter Sr , the cone angle parameter m , the mixed convection parameter  , the VHF/VMF exponent  , the non-Newtonian fluid power-law index n , the space-dependent internal heat source coefficient * A . The physical aspects of the problem are discussed in details.

show abstract

Throughflow Effect on Local and Large-scale Penetrative Convection in Superposed Air-porous Layer with Internal Heat Source Depending on Solid Fraction

Cited by 8 publications

References 19 publications

Heat Convection in a Channel-Opened Cavity with Two Heated Sources and Baffle

Heat Convection in a Channel-Opened Cavity with Two Heated Sources and Baffle

Formation of convective roll patterns over a longitudinal throughflow in an active inhomogeneous porous medium with weak clogging

Influence of Dufour/Soret and Space-Dependent Internal Heat Source on Combined Convection of Non-Newtonian Fluids Flow Past a Vertical Full Cone in Porous Media: The VHF/VMF Case

Contact Info

Product

Resources

About