Mingzhu Tang¹, Yujie Huang¹, Dongxu Ji², Hao Yu^2,*

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 95-129, 2025, DOI:10.32604/fhmt.2025.061143 - 26 February 2025

Abstract Load deviations between the output of ultra-supercritical (USC) coal-fired power units and automatic generation control (AGC) commands can adversely affect the safe and stable operation of these units and grid load dispatching. Data-driven diagnostic methods often fail to account for the imbalanced distribution of data samples, leading to reduced classification performance in diagnosing load deviations in USC units. To address the class imbalance issue in USC load deviation datasets, this study proposes a diagnostic method based on the multi-label natural neighbor boundary oversampling technique (MLNaNBDOS). The method is articulated in three phases. Initially, the traditional… More > Graphic Abstract

Abdelilah Makaoui¹, El Bachir Lahmer^1,*, Jaouad Benhamou^1,2, Mohammed Amine Moussaoui¹, Ahmed Mezrhab¹

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 207-230, 2025, DOI:10.32604/fhmt.2024.060166 - 26 February 2025

Abstract This study focuses on numerically investigating thermal behavior within a differentially heated cavity filled with nanofluid with and without obstacles. Numerical comparison with previous studies proves the consistency and efficacy of the lattice Boltzmann method associated with a single relaxation time and its possibility of studying the nanofluid and heat transfer with high accuracy. Key parameters, including nanoparticle type and concentration, Rayleigh number, fluid basis, and obstacle position and dimension, were examined to identify optimal conditions for enhancing heat transfer quality. Principal findings indicated that increasing the Rayleigh number boosts buoyancy forces and alters vortex More > Graphic Abstract

Shenghua Li¹, Kehan Liu², Bangxing Qian², Ziwei Wen², Bo Shi^2,*

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 231-248, 2025, DOI:10.32604/fhmt.2025.059963 - 26 February 2025

Abstract Phase change heat transfer devices like heat pipes are widely utilized in temperature control and heat transfer. However, the traditional single uniform wick makes it hard to meet the requirements of capillary pressure and permeability for high-performance heat pipes, thus limiting the improvement of heat transfer performance. In this paper, a gradient structure wick sintered by 316 L stainless steel powder is designed. The capillary performance is tested and characterized through permeability test experiments and capillary rise infrared test experiments. Moreover, the influence of different particle sizes of sintered powder on the capillary performance of More >

Hongkun Lu^1,2,*, M. M. Noor^2,3,4,*, K. Kadirgama²

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 299-324, 2025, DOI:10.32604/fhmt.2024.059871 - 26 February 2025

Abstract To improve the thermal performance and temperature uniformity of battery pack, this paper presents a novel battery thermal management system (BTMS) that integrates oscillating heat pipe (OHP) technology with liquid cooling. The primary innovation of the new hybrid BTMS lies in the use of an OHP with vertically arranged evaporator and condenser, enabling dual heat transfer pathways through liquid cooling plate and OHP. This study experimentally investigates the performance characteristics of the ⊥-shaped OHP and hybrid BTMS. Results show that lower filling ratios significantly enhance the OHP’s startup performance but reduce operational stability, with optimal… More >

Wei Zhang^*, Haojie Chen, Kunyu Cheng, Yulong Zhang

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 361-381, 2025, DOI:10.32604/fhmt.2025.059837 - 26 February 2025

Abstract The present work deals with the numerical study of the two-phase flow pattern and heat transfer characteristics of single-loop pulsating heat pipes (PHPs) under three modified surfaces (superhydrophilic evaporation section paired with superhydrophilic, superhydrophobic, and hybrid condensation section). The Volume of Fluid (VOF) model was utilized to capture the phase-change process within the PHPs. The study also evaluated the influence of surface wettability on fluid patterns and thermo-dynamic heat transfer performance under various heat fluxes. The results indicated that the effective nucleation and detachment of droplets are critical factors influencing the thermal performance of the… More > Graphic Abstract

Karim Amrani^1,*, Eugenia Rossi di Schio^2,*, Mohamed Bouzit³, Abderrahim Mokhefi^1,4, Abdelkader Aris¹, Cherif Belhout³, Paolo Valdiserri²

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 185-206, 2025, DOI:10.32604/fhmt.2025.059833 - 26 February 2025

Abstract The present study focuses on the flow of a yield-stress (Bingham) nanofluid, consisting of suspended Fe₃O₄ nanoparticles, subjected to a magnetic field in a backward-facing step duct (BFS) configuration. The duct is equipped with a cylindrical obstacle, where the lower wall is kept at a constant temperature. The yield-stress nanofluid enters this duct at a cold temperature with fully developed velocity. The aim of the present investigation is to explore the influence of flow velocity (Re = 10 to 200), nanoparticle concentration ( = 0 to 0.1), magnetic field intensity (Ha = 0 to 100), and… More >

Ziyi Wang^1,2, Sen Li^1,2,*, Xiaolin Wei^1,2, Jing Zhao¹, Bo Li¹, Yuan Yao¹

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 163-184, 2025, DOI:10.32604/fhmt.2024.059740 - 26 February 2025

Abstract In the novel fully dry converter gas recovery process, a novel circumfluent cyclone separator with an evaporation heating surface can simultaneously realize the dust removal and sensible heat recovery of converter gas. For this equipment, the distributions of internal flow and wall heat transfer affect the efficiency of dust removal and sensible heat recovery. In this study, based on on-site operation tests, the distributions of internal flow and wall heat transfer in the circumfluent cyclone separator are studied by numerical simulation. The results indicate that the flow rate proportions in different regions of the circumfluent More >

Sudipta Debnath¹, Zahir Uddin Ahmed², Muhammad Ikhlaq^3,4,*, Md. Tanvir Khan⁵, Avneet Kaur⁶, Kuljeet Singh Grewal¹

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 71-94, 2025, DOI:10.32604/fhmt.2024.059734 - 26 February 2025

Abstract Impinging jet arrays are extensively used in numerous industrial operations, including the cooling of electronics, turbine blades, and other high-heat flux systems because of their superior heat transfer capabilities. Optimizing the design and operating parameters of such systems is essential to enhance cooling efficiency and achieve uniform pressure distribution, which can lead to improved system performance and energy savings. This paper presents two multi-objective optimization methodologies for a turbulent air jet impingement cooling system. The governing equations are resolved employing the commercial computational fluid dynamics (CFD) software ANSYS Fluent v17. The study focuses on four… More > Graphic Abstract

Gehad Azmy, Mohamed El-Morsi, Omar Abdelaziz^*

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 1-54, 2025, DOI:10.32604/fhmt.2025.059710 - 26 February 2025

Abstract This review paper presents an in-depth investigation of the modeling techniques used to study conveyor belt dryers. These techniques are classified into four categories: theoretical modeling, computational fluid dynamics (CFD), empirical, and performance under different control strategies. Within the theoretical and CFD categories, the models are further classified as transient and steady state, as well as one-dimensional, two-dimensional, and three-dimensional. The empirical approach involves conducting experimental studies to collect moisture ratio data during the drying process and comparing it with empirical models. The methods of control are divided into classical and advanced controllers, with classical… More >

Yiming Rongyang¹, Zhenyue Yu¹, Ruisheng Liang^2,*, Wei Su¹, Jianjian Wei^2,3

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 279-298, 2025, DOI:10.32604/fhmt.2025.059637 - 26 February 2025

Abstract Data center cooling systems are substantial energy consumers, and managing the heat generated by electronic devices is becoming more complex as chip power levels continue to rise. The single-phase immersion cooling (SPIC) server with oil coolant is numerically investigated using the validated Re-Normalization Group (RNG) k-ε model. For the investigated scenarios where coolant velocity at the tank inlet is 0.004 m/s and the total power is 740 W, the heat transfer between the heat sinks and the coolant is dominated by natural convection, although forced convection mediates the overall heat transfer inside the tank. The maximum… More >