Hongen Li, Hongjuan Ren^*, Cong Li, Yecui Yan

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 921-941, 2025, DOI:10.32604/fhmt.2025.066512 - 30 June 2025

Abstract The flow field architecture of the proton exchange membrane fuel cell (PEMFC) cathode critically determines its performance. To enhance PEMFC operation through structural optimization, trapezoidal obstacles were implemented in the cathode flow channels. The height dependence of these obstacles was systematically investigated, revealing that a 0.7 mm obstacle height enhanced mass transfer from channels to the gas diffusion layer (GDL) compared to conventional triple-serpentine designs. This configuration achieved a 12.08% increase in limiting current density alongside improved water management. Subsequent studies on obstacle distribution density identified 75% density as optimal, delivering maximum net power density More >

Zerui Chen^*, Xin Wu, Houpeng Hu, Yang Zhou, Shang Yang

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 991-1011, 2025, DOI:10.32604/fhmt.2025.065936 - 30 June 2025

Abstract As the integration of electronic components in high-performance servers increases, heat generation significantly impacts performance and raises failure rates. Therefore, heat dissipation has become a critical concern in electronic circuit design. This study uses numerical simulations to investigate the heat dissipation characteristics of electronic components in air-cooled servers. By adjusting airflow speed, heat sink configurations, and the arrangement of straight-fin heat sinks, we optimize heat dissipation performance and analyze the mechanisms at different airflow speeds. The results show that, at the same airflow speed, the temperature of the heat sink is lower than that of… More >

Basima Salman Khalaf^*, Abeer H. Falih, Basim Freegah

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 943-956, 2025, DOI:10.32604/fhmt.2025.065366 - 30 June 2025

Abstract The main purpose of this research is to optimize the hydrothermal performance of a dimpled tube by augmenting the surface area for heat transmission and thermal layer cracking. To achieve that, the impact of different dimple diameters and their distribution along the dimpled tube was investigated numerically using the ANSYS Fluent 2022 R1 software by considering two models, A and B. Both models consist of three regions; the first, second, and third have dimple diameters of 3, 2, & 1 mm, respectively. Model A included an in-line dimple arrangement, while model B involved a staggered… More >

Mohammed Salam Abdl Ghafoor, Mohammed K. Al-Saadi, Ameer Abed Jaddoa^*

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 975-990, 2025, DOI:10.32604/fhmt.2025.064025 - 30 June 2025

Abstract The comparison of experimental performance was studied for soda cans: longitudinal, transverse, diagonal, and smooth cases to improve the heat transfer rate and thermal performance of the solar air heater, in this study using a frame which has 1.5 m × 0.5 m × 0.05 m dimensions, the arrangements were placed on the absorber plate inside the channel, raising the air’s exit temperature as it passed by. The work was carried out for 4 cases in January in Baghdad, Iraq, under specific conditions to compare them to reach the ideal case and the best performance… More >

Chao Zhang¹, Runze Yan¹, Honghui Li¹, Qingheng Tang¹, Qinghai Zhao^1,2,*

Frontiers in Heat and Mass Transfer, Vol.23, No.2, pp. 421-440, 2025, DOI:10.32604/fhmt.2025.061469 - 25 April 2025

Abstract The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers. Innovation inspired by nature bionics, four types of leaf-shaped pin fins were proposed and four combinations of them were considered. The leaf-shaped design of the cooling pin fin enhances uniformity and synergy, effectively creating an optimized flow path that boosts cooling performance. Eight three-dimensional conjugate heat transfer models in staggered arrangement were developed using ANSYS-Fluent software. Aluminum 6061 material was used as the heat sink material and single-phase liquid water flowed through the rectangular channel where the Reynolds (Re) number… More >

Shuaijie Jiang¹, Zechen Zhou¹, Xiuli Wang¹, Wei Xu², Wenzhuo Guo¹, Qingjiang Xiang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.3, pp. 471-491, 2025, DOI:10.32604/fdmp.2025.059878 - 01 April 2025

Abstract In nature, cavitation bubbles typically appear in clusters, engaging in interactions that create a variety of dynamic motion patterns. To better understand the behavior of multiple bubble collapses and the mechanisms of inter-bubble interaction, this study employs molecular dynamics simulation combined with a coarse-grained force field. By focusing on collapse morphology, local density, and pressure, it elucidates how the number and arrangement of bubbles influence the collapse process. The mechanisms behind inter-bubble interactions are also considered. The findings indicate that the collapse speed of unbounded bubbles located in lateral regions is greater than that of More >

STEPHEN E. LANGABEER^*

Oncology Research, Vol.32, No.9, pp. 1423-1427, 2024, DOI:10.32604/or.2024.051218 - 23 August 2024

Abstract Hairy cell leukemia (HCL) is an uncommon mature B-cell malignancy characterized by a typical morphology, immunophenotype, and clinical profile. The vast majority of HCL patients harbor the canonical BRAF V600E mutation which has become a rationalized target of the subsequently deregulated RAS-RAF-MEK-MAPK signaling pathway in HCL patients who have relapsed or who are refractory to front-line therapy. However, several HCL patients with a classical phenotype display non-canonical BRAF mutations or rearrangements. These include sequence variants within alternative exons and an oncogenic fusion with the IGH gene. Care must be taken in the molecular diagnostic work-up of patients More >

Abeer H. Falih^*, Basima Salman Khalaf, Basim Freegah

Frontiers in Heat and Mass Transfer, Vol.22, No.2, pp. 597-613, 2024, DOI:10.32604/fhmt.2024.049812 - 20 May 2024

Abstract In this study, the primary objective was to enhance the hydrothermal performance of a dimpled tube by addressing areas with low heat transfer compared to other regions. To accomplish this, a comprehensive numerical investigation was conducted using ANSYS Fluent 2022 R1 software, focusing on different diameters of dimples along the pipe’s length and the distribution of dimples in both in-line and staggered arrangements. The simulations utilized the finite element method to address turbulent flow within the tube by solving partial differential equations, encompassing Re numbers spanning from 3000 to 8000. The study specifically examined single-phase… More > Graphic Abstract

Xiang Lin^1,*, Jian Fang¹, Ming Zhang¹, Kuang Yin¹, Yan Tian¹, Yingfei Guo², Qianggang Wang²

Energy Engineering, Vol.121, No.5, pp. 1127-1141, 2024, DOI:10.32604/ee.2024.046861 - 30 April 2024

Abstract Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency (UHF) antennas for detecting partial discharge (PD) as a common precursor to faults. However, the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth, relatively large physical size, and low detection sensitivity. The present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm × 100 mm × 1.6 mm. The results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units More > Graphic Abstract

Qianqian Shao¹, Min Wang^2,*, Nuo Xu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1337-1356, 2024, DOI:10.32604/cmes.2023.044313 - 29 January 2024

Abstract To investigate the influences of co-flow and counter-flow modes of reactant flow arrangement on a proton exchange membrane fuel cell (PEMFC) during start-up, unsteady physical and mathematical models fully coupling the flow, heat, and electrochemical reactions in a PEMFC are established. The continuity equation and momentum equation are solved by handling pressure-velocity coupling using the SIMPLE algorithm. The electrochemical reaction rates in the catalyst layers (CLs) of the cathode and anode are calculated using the Butler-Volmer equation. The multiphase mixture model describes the multiphase transport process of gas mixtures and liquid water in the fuel… More >