Shengzhong Zhao¹, Daiyan Chen¹, Han Zhang^1,2,*, Junhao Yu¹, Lin Xu¹, Zhaoyi Zhuang¹, Fei Wang^1,*

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1907-1932, 2025, DOI:10.32604/fhmt.2025.071910 - 31 December 2025

Abstract A sealed portal could significantly alter the flame shape and smoke flow characteristics in inclined tunnel fires. In inclined tunnels, two typical sealing conditions could be defined, namely the upper portal sealed and the lower portal sealed. In this study, the effects of tunnel slope on flame shape, flame length, along with smoke mass flow rate and induced velocity at the tunnel portal, are numerically investigated. The results show that, in all scenarios, flames initially rise vertically but tilt toward the sealed portal during the quasi-steady stage, with the largest tilt angle observed in tunnels… More >

Xiaolong Li, Hui Chen, Yingwen Liu, Peng Yang^*

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1767-1788, 2025, DOI:10.32604/fhmt.2025.070537 - 31 December 2025

Abstract Hazardous gas intrusion in tightly sealed and geometrically complex confined spaces, such as armored tanks, poses a critical threat to occupant health. The intricate internal structure of these systems may lead to non-intuitive pollutant transport pathways. However, the spatial and temporal evolution of these structures, as well as the intrinsic mechanisms of the purification systems, remain poorly elucidated. In this study, a high-fidelity, transient three-dimensional computational fluid dynamics (CFD) model was developed to simulate the leakage and dispersion of carbon monoxide (CO) and nitrogen dioxide (NO₂) using the RNG k-ε turbulence model. Scenarios with and without… More > Graphic Abstract

Ghinwa Al Mimar¹, Natrah Kamaruzaman^1,*, Kamil Talib Alkhateeb²

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1933-1956, 2025, DOI:10.32604/fhmt.2025.070118 - 31 December 2025

Abstract The pivotal role microchannels play in the thermal management of electronic components has, in recent decades, prompted extensive research into methods for enhancing their heat transfer performance. Among these methods, surface wettability modification was found to be highly effective owing to its significant influence on boiling dynamics and heat transfer mechanisms. In this study, we modified surface wettability using a nanocomposite coating composed of graphene nano plate (GNPs) and multi-walled carbon nanotubes (MWCNT) and then examined how the modification affected the transfer of boiling heat in microchannels. The resultant heat transfer coefficients for hydrophilic and… More >

J. Serrano-Arellano¹, M.I. Hernández-López¹, J. L. Chávez-Servín², E. V. Macias-Melo³, K. M. Aguilar-Castro^3,*

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1741-1765, 2025, DOI:10.32604/fhmt.2025.069560 - 31 December 2025

Abstract A numerical study analyzed double diffusion caused by convective and radiative heat transfer in a greenhouse with and without internal humidity sources. Two cases were examined: one considering temperature and mass concentration gradients on vertical walls and another incorporating internal humidity sources, enhancing convective and diffusive flows. Four configurations were analyzed by varying the length of the greenhouse, and the Rayleigh number was calculated over a range from 2.29 × 10¹⁰ to 6.07 × 10¹². Simulations modeled the greenhouse interior six times a day (8:00 a.m. to 7:00 p.m.), accounting for external temperature, humidity, and solar More > Graphic Abstract

Du-Yi Wang¹, Shih-Chen Shi^1,*, Dieter Rahmadiawan^1,2

Journal of Polymer Materials, Vol.42, No.4, pp. 1075-1095, 2025, DOI:10.32604/jpm.2025.072263 - 26 December 2025

Abstract Polymethyl methacrylate (PMMA) is widely used in diverse applications such as protective components (e.g., automotive lamp covers and structural casings), optical devices, and biomedical products, owing to its lightweight nature and impact resistance. However, its surface hardness and wear resistance remain insufficient under prolonged exposure to abrasive environments. In this study, a multi-filler strategy with nano-silica (SiO₂), brominated lignin (Br-Lignin), and cellulose nanocrystals (CNCs) was employed to enhance PMMA tribological properties. SiO₂ provided localized reinforcement, Br-Lignin established stable network structures, and CNCs improved compactness, enabling strong synergistic effects. As a result, the composites achieved up to More >

Asgar Ali^1,*, Nayan Sardar², Poly Karmakar³, Sanatan Das⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.3, pp. 3563-3626, 2025, DOI:10.32604/cmes.2025.074082 - 23 December 2025

Abstract Hybrid nanofluids have gained significant attention for their superior thermal and rheological characteristics, offering immense potential in energy conversion, biomedical transport, and electromagnetic flow control systems. Understanding their dynamic behavior under coupled magnetic, rotational, and reactive effects is crucial for the development of efficient thermal management technologies. This study develops a neuro-fuzzy computational framework to examine the dynamics of a reactive Cu–TiO₂–H₂O hybrid nanofluid flowing through a squarely elevated Riga tunnel. The governing model incorporates Hall and ion-slip effects, thermal radiation, and first-order chemical reactions under ramped thermo-solutal boundary conditions and rotational electromagnetic forces. Closed-form analytical… More >

Mujahid Islam¹, Fateh Ali^1,*, Xinlong Feng^1,*, M. Zahid², Sana Naz Maqbool¹

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.3, pp. 3511-3561, 2025, DOI:10.32604/cmes.2025.073678 - 23 December 2025

Abstract Roll coating is a vital industrial process used in printing, packaging, and polymer film production, where maintaining a uniform coating is critical for product quality and efficiency. This work models non-isothermal Carreau fluid flow between a rotating roll and a stationary wall under fixed boundary constraints to evaluate how non-Newtonian and thermal effects influence coating performance. The governing equations are transformed into non-dimensional form and simplified using lubrication approximation theory. Approximate analytical solutions are obtained via the perturbation technique, while numerical results are computed using both the finite difference method and the BVP-Midrich technique. Furthermore, More >

Amina Mahreen¹, Fateh Mebarek-Oudina^2,3,4,*, Amna Ashfaq¹, Jawad Raza¹, Sami Ullah Khan⁵, Hanumesh Vaidya⁶

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.11, pp. 2829-2853, 2025, DOI:10.32604/fdmp.2025.072492 - 01 December 2025

Abstract Understanding the complex interaction between heat and mass transfer in non-Newtonian microflows is essential for the development and optimization of efficient microfluidic and thermal management systems. This study investigates the magnetohydrodynamic (MHD) thermosolutal convection of a Casson fluid within an inclined, porous microchannel subjected to convective boundary conditions. The nonlinear, coupled equations governing momentum, energy, and species transport are solved numerically using the MATLAB bvp4c solver, ensuring high numerical accuracy and stability. To identify the dominant parameters influencing flow behavior and to optimize transport performance, a comprehensive hybrid optimization framework—combining a modified Taguchi design, Grey… More >

Yuxin Wang¹, Youjiang Wang², Jieping Wang², Chao Zhang^1,*, Fanguang Meng³, Linhua Zhang¹, Yongxing Song^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.11, pp. 2761-2777, 2025, DOI:10.32604/fdmp.2025.072236 - 01 December 2025

Abstract High-pressure water jet technology has emerged as a highly effective method for removing industrial-scale deposits from pipelines, offering a clean, efficient, and environmentally sustainable alternative to conventional mechanical or chemical cleaning techniques. Among the many parameters influencing its performance, the geometry of the nozzle plays a decisive role in governing jet coherence, impact pressure distribution, and overall cleaning efficiency. In this study, a comprehensive numerical and experimental investigation is conducted to elucidate the influence of nozzle geometry on the behavior of high-pressure water jets. Using Computational Fluid Dynamics (CFD) simulations based on the Volume of… More >

Zhenzhen Shen^1,2, Kang Yang², Dengfeng Wei², Quansheng Liang², Zhenpeng Ma², Hong Wang², Keyu Wang², Chunwei Zhang², Xiaohu Yang^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.11, pp. 2741-2760, 2025, DOI:10.32604/fdmp.2025.070395 - 01 December 2025

Abstract The rapid prediction of seepage mass flow in soil is essential for understanding fluid transport in porous media. This study proposes a new method for fast prediction of soil seepage mass flow by combining mesoscopic modeling with deep learning. Porous media structures were generated using the Quartet Structure Generation Set (QSGS) method, and a mesoscopic-scale seepage calculation model was applied to compute flow rates. These results were then used to train a deep learning model for rapid prediction. The analysis shows that larger average pore diameters lead to higher internal flow velocities and mass flow More >