Chen Zhu¹, Xiao Ma¹, Lumin Chen², Qi Ma¹, Yi Sun¹, Fuping Qian^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.8, pp. 1895-1915, 2025, DOI:10.32604/fdmp.2025.067899 - 12 September 2025

Abstract The rotary gas-gas heat exchanger (GGH) is a vital component in waste heat recovery systems, particularly for Selective Catalytic Reduction (SCR) processes employed in cement kiln operations. This study investigates the thermal performance of a rotary GGH in medium- and low-temperature denitrification systems, using a simplified porous medium model based on its actual internal structure. A porous medium representation is developed from the structural characteristics of the most efficient heat transfer element, and a local thermal non-equilibrium (LTNE) model is employed to capture the distinct thermal behaviors of the solid matrix and gas phase. To… More >

Jinping Xu^1,2, Zhiyun Wang¹, Mo Yang^1,*

Frontiers in Heat and Mass Transfer, Vol.23, No.4, pp. 1151-1163, 2025, DOI:10.32604/fhmt.2025.067925 - 29 August 2025

Abstract In concentric annular pipes, the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces. The simplifications of the Dittus-Boelter equation for circular pipes make it unsuitable for the complex flow induced by the geometry and heat transfer coupling effects in annular pipes. This prevents it from accurately predicting the turbulent heat transfer in concentric annular pipes. This paper used realizable κ–ε and low Reynolds number models to conduct numerical simulations of turbulent convective heat transfer in concentric annular pipes and circular pipes.… More >

Ying Zhang^1,2, Chao Dang^1,2,*, Zhiqiang Zhang^1,2

Frontiers in Heat and Mass Transfer, Vol.23, No.4, pp. 1215-1242, 2025, DOI:10.32604/fhmt.2025.067373 - 29 August 2025

Abstract In this study, the flow boiling characteristics of R1234yf in parallel microchannels were experimentally investigated. The experiments were conducted with heat flux from 0 to 550 kW/m², mass flux of 434, 727, and 1015 kg/(m² s), saturation temperatures of 293, 298, and 303 K, and inlet sub-cooling of 5, 10, and 15 K. The analysis of the experimental results provides the following conclusions: a reduced mass flux and lower subcooling correspond to a diminished degree of superheat at the boiling inception wall; conversely, an elevated saturation temperature results in a reduced amount of superheat at the… More >

Meriem Bounib¹, Aicha Bouhezza^2,3,*, Abdelkrim Khelifa⁴, Mohamed Teggar⁵, Hasan Köten⁶, Aissa Atia⁷, Yassine Cherif ⁸

Frontiers in Heat and Mass Transfer, Vol.23, No.4, pp. 1323-1350, 2025, DOI:10.32604/fhmt.2025.065254 - 29 August 2025

Abstract This study investigates laminar convection in three regimes (forced convection, mixed convection, and natural convection) of a bi-nanofluid (Cu-Al₂O₃-water)/mono-nanofluid (Al₂O₃-water) inside a square enclosure of sliding vertical walls which are kept at cold temperature and moving up, down, or in opposite directions. The enclosure bottom is heated partially by a central heat source of various sizes while the horizontal walls are considered adiabatic. The thermal conductivity and dynamic viscosity are dependent on temperature and nanoparticle size. The conservation equations are implemented in the solver ANSYS R2 (2020). The numerical predictions are successfully validated by comparison with… More >

Khadija Ibaararen, Mhammed Zaimi, Khadija El Ainaoui, El Mahdi Assaid^*

Energy Engineering, Vol.122, No.9, pp. 3487-3505, 2025, DOI:10.32604/ee.2025.067422 - 26 August 2025

Abstract This study investigates the complex heat transfer dynamics in multilayer bifacial photovoltaic (bPV) solar modules under spectrally resolved solar irradiation. A novel numerical model is developed to incorporate internal heat generation resulting from optical absorption, grounded in the physical equations governing light-matter interactions within the module’s multilayer structure. The model accounts for reflection and transmission at each interface between adjacent layers, as well as absorption within individual layers, using the wavelength-dependent dielectric properties of constituent materials. These properties are used to calculate the spectral reflectance, transmittance, and absorption coefficients, enabling precise quantification of internal heat… More >

Abdelhakim Lahrech¹, Tahar Tayebi², Mohamed Kallel^3,*, Mehdi Hashemi-Tilehnoee^4,*, Ali J. Chamkha⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.144, No.1, pp. 359-385, 2025, DOI:10.32604/cmes.2025.067099 - 31 July 2025

Abstract The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus. Two equations are assumed to evaluate the thermal fields in the porous medium under Local Thermal Non-Equilibrium (LTNE) conditions, along with the Darcy-Brinkman-Forchheimer model for the flow. By imposing distinct and constant temperatures and concentrations on both internal and external cylinders, thermosolutal natural convection is induced in the annulus. We apply the finite volume method to solve the dimensionless governing equations numerically. The thermal conductivity and viscosity of the nanofluid mixture are determined utilizing… More >

Liaofei Yin^1,*, Kexin Zhang¹, Tianjun Qin¹, Wenhao Ma¹, Yi Ding¹, Yawei Xu^2,*

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 751-764, 2025, DOI:10.32604/fhmt.2025.067385 - 30 June 2025

Abstract Flow boiling in open microchannels offers highly efficient heat transfer performance and has attracted increasing attention in the fields of heat transfer and thermal management of electronic devices in recent years. However, the continuous rise in power density of electronic components imposes more stringent requirements on the heat transfer capability of microchannel flow boiling. HFE-7100, a dielectric coolant with favorable thermophysical properties, has become a focal point of research for enhancing flow boiling performance in open microchannels. The flow boiling heat transfer performance of HFE-7100 was investigated in this study by fabricating micro-nano composite structures… More >

Xingjie Ren^1,2,#,*, Jianrong Zhang^3,4,#, Qingfeng Tang³, Heng Zhang³, Yaling Zhang^3,4,*

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 881-897, 2025, DOI:10.32604/fhmt.2025.066302 - 30 June 2025

Abstract This paper investigates interfacial heat transfer characteristics in a multi-layer structure under ultra-high heat flux conditions, focusing on thermal contact resistance (TCR) between adjacent layers. A three-layer computational model with dual rough interfaces was developed to systematically analyze the synergistic effects of interfacial pressure, surface emissivity, and thermal interface materials (TIMs). Surface reconstruction using experimental measurement data generated two representative roughness models to quantify the impact of surface roughness on heat dissipation. Numerical simulations demonstrate that the absence of TIMs leads to insufficient thermal dissipation capacity under ultra-high heat flux conditions. Compared to TIM application, More >

Ans Ahmed Memon¹, Laveet Kumar^1,2,*, Abdul Ghafoor Memon¹, Khanji Harijan¹, Ahmad K. Sleiti²

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 833-856, 2025, DOI:10.32604/fhmt.2025.064805 - 30 June 2025

Abstract Climate change, rising fuel prices, and fuel security are some challenges that have emerged and have grown worldwide. Therefore, to overcome these obstacles, highly efficient thermodynamic devices and heat recovery systems must be introduced. According to reports, much industrial waste heat is lost as flue gas from boilers, heating plants, etc. The primary objective of this study is to investigate and compare unary (Al₂O₃) thermodynamically, binary with three different combinations of nanoparticles namely (Al₂O₃ + TiO₂, TiO₂ + ZnO, Al₂O₃ + ZnO) and ternary (Al₂O₃ + TiO₂ + ZnO) as a heat transfer fluid. Initially, three different types of… More > Graphic Abstract

Rajiva Lochan Mohanty, Sumanta Chaudhuri^*, Anish Pandey

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 899-919, 2025, DOI:10.32604/fhmt.2025.064444 - 30 June 2025

Abstract Characteristics of heat transfer and flow of Newtonian and non-Newtonian fluids through porous walls and in porous media are studied due to their wide range of applications including geothermal reservoirs, heat exchangers, marine propulsion, and aerodynamics. The current study investigates the characteristics of heat transport in a reactive third-grade fluid, moving through permeable parallel plates, with uniform suction/injection velocity. The two permeable, parallel plates are maintained at the same, constant temperature. After being transformed into its dimensionless equivalent, governing equations are solved by employing the Least Squares Method (LSM). The LSM results are further validated… More >