Convective heat transfer analysis in turbulent nanofluid flow through a rectangular channel with staggered obstacles: A numerical simulation

International Journal of Thermofluids, Год журнала: 2024, Номер 23, С. 100753 - 100753

Опубликована: Июль 1, 2024

This study explores the hydraulic and thermal characteristics of a staggered rectangular baffled channel. The first baffle is inserted in top channel surface, with subsequent baffles placed on bottom. Numerical simulations were conducted across Reynolds number range 5000 to 50,000. In this three different inclination angles are examined: Case A involves obstacles perpendicular wall, while Cases B C feature inclined at ±10 ° surface. Three types nanoparticles (SiO2, Al2O3, CuO) added base fluid (pure water) volume fraction 4 % formulate nanofluids utilized study. Computational Fluid Dynamics (CFD) performed using ANSYS Fluent software, solve governing equations. numerical results validated against experimental data, demonstrating good agreement. findings reveal that maximum enhancement factor 2 for A. Additionally, heat transfer coefficient experiences 10.3 increase water-CuO nanofluid compared pure water highest average Nusselt observed water, reaching 812

Язык: Английский

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Enhancing photovoltaic thermal (PVT) performance with hybrid solar collector using phase change material, porous media, and nanofluid

Solar Energy, Год журнала: 2024, Номер 283, С. 112983 - 112983

Опубликована: Окт. 14, 2024

Язык: Английский

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Investigation of natural convection and entropy generation of non-Newtonian flow in molten polymer-filled odd-shaped cavities using finite difference lattice Boltzmann method

Numerical Heat Transfer Part B Fundamentals, Год журнала: 2024, Номер unknown, С. 1 - 26

Опубликована: Май 10, 2024

This study examines the natural convection heat transfer (NCHT) and entropy generation (EG) of a non-Newtonian (NN) flow inside an odd-shaped cavity filled with molten polymer. The configuration comprises hot internal walls, cold external insulated remaining walls. finite difference lattice Boltzmann method (FDLBM) is employed to solve governing equations involved. input parameters span range values, Rayleigh number (Ra) varying from 104 105, power-law index (n) covering 0.5 1.5, width ratio (WR) ranging 0.2 0.4, while maintaining Prandtl (Pr) at constant value 10. results revealed that Ra values overall increases as WR 0.4 decreases n increases. In contrast dilatant fluids, where (HT) 1 pseudo-plastic fluids show opposite trend HT increasing 0.5. attributed general decrease in average Nusselt (Nu) Additionally, it observed has no significant impact on Nu due low buoyancy force = WRs 0.3. However, notably influences Bejan (Be) across all WRs. Overall, present model demonstrates excellent agreement previous numerical results, affirming FDLBM superior, reliable, well-suited technique for relevant applications. These suggest potential extend application approach various shapes, allowing comprehensive exploration NCHT EG under conditions.

Язык: Английский

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Efficiency Enhancement in Direct Thermal Energy Storage Systems Using Dual Phase Change Materials and Nanoparticle Additives

Case Studies in Thermal Engineering, Год журнала: 2024, Номер 59, С. 104577 - 104577

Опубликована: Май 20, 2024

The study aims to enhance the reliability of direct thermal energy storage (TES) using phase change materials (PCMs) and nanoparticles, ensuring sustained heat supply even during periods low or intermittent solar radiation. specifically investigates a TES system comprising double-cylindrical shell container with two distinct PCM types: petroleum jelly petrolatum 1% Al2O3 nanoparticles by volume in outer wax inner shell. Additionally, redesigned exchanger is employed improve heating efficiency. examines configurations: an open closed water tank. deliberate strategy augmenting aimed at enhancing transfer both charging discharging phases. performance configurations compared, focus on highlighting temperature profiles processes. incorporation PCMs led significant enhancement efficiency, two-phase case achieving highest efficiency 73%. Furthermore, utilization resulted improvement approximately 5%. These findings demonstrate potential dual layers NPs additives systems.

Язык: Английский

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Electromagnetic mixed convective flow of dusty hyperbolic tangent hybrid nanofluid over a stretching surface: A quadratic regression analysis using RSM

International Journal of Thermofluids, Год журнала: 2024, Номер 23, С. 100803 - 100803

Опубликована: Авг. 1, 2024

Язык: Английский

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Numerical investigation of thermal and entropy generation characteristics in a sinusoidal corrugated channel under the influence of sinusoidal wall temperature

International Journal of Thermofluids, Год журнала: 2024, Номер 22, С. 100706 - 100706

Опубликована: Май 1, 2024

The corrugated channels play a vital role in many engineering applications, such as electronic cooling and heat exchanger devices; thus, forced convection transfer entropy generation within the are important subjects to investigate. This study numerically investigated laminar of water flow sinusoidal channel. channel walls were subjected wall temperature heating while varying wave parameters. finite element method had been employed solve governing equation, simulation results conducted for Reynolds number 5 ≤ Re 500, dimensionless wavelength 0.25 λth 2.25, Prandtl Pr = 6.93. main findings depicted terms Nusselt number, skin friction coefficient, effectiveness, total generation, Bejan contours, well being compared with uniform heating. In addition, demonstrated that significantly improved < 1.75 all ranges critical was found, where showed higher rate non-uniform at ≥ . Besides that, it is found has lower than heating, except 0.25. investigation recommends more effective by 7.5, 2.78, 1.9, 1.52, 1.34 factors 0.25, 0.75, 1.25, respectively.

Язык: Английский

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Natural convective Cu-water nanofluid flow in isosceles triangular cavity with forced free stream cooled sides and localized heated base

International Journal of Thermofluids, Год журнала: 2024, Номер 23, С. 100766 - 100766

Опубликована: Июль 16, 2024

The present paper aims to conduct a numerical investigation of the natural convective flow Cu-water nanofluid in an isosceles triangular-shaped cavity, where air stream cools lateral walls while its base is subjected discrete heating. governing equations are numerically solved using finite volume method (FVM) employing ANSYS FLUENT. results presented with diverse scopes pertinent parameters, including non-dimensional heater length (L/H = 0.25, 0.5, and 1), Rayleigh Number (Ra 104, 105, 106), nanoparticles fraction (φ 0, 0.03, 0.06 0.09), free Reynolds number (Re∞ 102, 103, 104 105). impact each these parameters depicted on isotherms (θ) lines, function (ψ) contours, average Nusselt (Nuavg) plots heated lower wall. findings showed subsequent enlargements Nuavg increase Ra by 515 %, L/H 130 Re∞ 43 φ 137 indicating enhancement heat transfer rate parameters. Besides, extra secondary eddies will be generated inside cavity when becomes more extensive, configuration not influenced enlargement φ, Re∞, L/H. model have been compared other work from literature acceptable agreement maximum error less than 1 %.

Язык: Английский

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Investigating Flow and Heat Distribution of NE‐PCM in a Double Lid‐Driven MHD Octagonal Chamber

Heat Transfer, Год журнала: 2025, Номер unknown

Опубликована: Март 20, 2025

ABSTRACT Mixed heat transfer, commonly encountered in engineering applications, has led to a strong focus on maximizing transmission rates. This study explores transfer enhancement within magnetohydrodynamic (MHD) double lid‐driven octagonal cavity. The cavity is filled with porous media and loaded nano‐encapsulated phase change material (NE‐PCM), subjected uniform magnetic field. Galerkin finite element method (GFEM) employed solve the governing equations. Key factors investigated include lid speed (Reynolds number, Re = 1–500), wall movement directions, field intensity (Hartmann Ha 0–100), porosity (Darcy Da 10 −5 –10 −2 ) their effects numerical was validated by comparing results well‐documented data from literature. findings reveal that higher values significantly enhance rates, while reduce Specifically, at highest Re, increasing enhanced averaged Nusselt number ( Nu 165%, 0 100 decreased it 16%. Additionally, moving both walls same direction improved average 350% compared opposing movement. also found NE‐PCM concentration had minimal impact efficiency, reducing chamber permeability hindered suspension movement, thereby between hot cold surfaces.

Язык: Английский

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Enhancing the efficiency of a double tube heat exchanger via a novel vibrating woven wire turbulator combined with a helical coiled wire; an experimental study

Applied Thermal Engineering, Год журнала: 2024, Номер 248, С. 123121 - 123121

Опубликована: Апрель 6, 2024

Язык: Английский

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MHD double diffusive mixed convection and heat generation / absorption in a lid-driven inclined wavy enclosure filled with a ferrofluid

International Journal of Thermofluids, Год журнала: 2024, Номер 22, С. 100698 - 100698

Опубликована: Май 1, 2024

The magneto-hydrodynamics (MHD) double-diffusive mixed convection and heat generation/absorption in a lid-driven inclined wavy enclosure filled with (Fe3O4/ water) ferrofluid is quantitatively investigated this paper. present study focuses on improving the efficiency of mass thermal performance system. Both left right sidewalls cavity are allowed to move constant velocity upward downward directions, respectively. finite difference approach was applied discretize subsequent governing equations followed by Bi-Conjugate Gradient Stabilized (Bi-CGStab) method solve them. numerical simulation performed for variety parameters, including Hartmann number varied as 0 ≤ Ha 45, inclination angle 0o δ 180o, buoyancy ratio -2 N 2, generation or absorption parameter -10 Qo 10, Richardson 0.01 Ri solid volume fraction ϕ 0.06. results were presented terms streamlines, isotherms, isoconcentrations, average Nusselt number, Sherwood number. transfer rates found decrease increase but N, Ri, Φ. Also, both them reach their peak values at = 10. In addition, enhances they maximum Increasing factor from 5 10 increases 3.5 times. outcomes have significant importance modern industrial applications specifically discipline electronic device cooling.

Язык: Английский

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