Rafah H. Zaidan^*, Najim A. Jasim

Frontiers in Heat and Mass Transfer, Vol.23, No.5, pp. 1595-1620, 2025, DOI:10.32604/fhmt.2025.068205 - 31 October 2025

Abstract This paper presents a comprehensive experimental and numerical investigation of radiant floor heating (RFH) systems integrated with phase change material (PCM)-based thermal energy storage (TES). The study compares two underfloor pipe configurations: double serpentine and spiral. It also looks at how well a paraffin wax PCM system works with compact heat exchanger-type TES units during winter in Iraq. Key performance indicators including discharge temperature, heat transfer rate, liquid fraction evolution, and temperature uniformity were assessed through in situ experimental measurements and ANSYS fluent simulations. Results demonstrate that the spiral design provides slightly more uniform temperature distribution… More >

Siham Essahraui¹, Ismail Lamaakal¹, Yassine Maleh^2,*, Khalid El Makkaoui¹, Mouncef Filali Bouami¹, Ibrahim Ouahbi¹, May Almousa³, Ali Abdullah S. AlQahtani⁴, Ahmed A. Abd El-Latif^5,6

CMC-Computers, Materials & Continua, Vol.85, No.2, pp. 3151-3183, 2025, DOI:10.32604/cmc.2025.067359 - 23 September 2025

Abstract The rapid shift to online education has introduced significant challenges to maintaining academic integrity in remote assessments, as traditional proctoring methods fall short in preventing cheating. The increase in cheating during online exams highlights the need for efficient, adaptable detection models to uphold academic credibility. This paper presents a comprehensive analysis of various deep learning models for cheating detection in online proctoring systems, evaluating their accuracy, efficiency, and adaptability. We benchmark several advanced architectures, including EfficientNet, MobileNetV2, ResNet variants and more, using two specialized datasets (OEP and OP) tailored for online proctoring contexts. Our findings More >

Orkhan Jafarli^*

Energy Engineering, Vol.122, No.9, pp. 3595-3608, 2025, DOI:10.32604/ee.2025.067982 - 26 August 2025

Abstract This study investigates the feasibility and efficiency of geothermal energy for heating applications in Azerbaijan, with a specific focus on the Khachmaz region. Despite the country’s growing interest in sustainable energy, limited research has addressed the potential of ground-source heat pump (GSHP) systems under local climatic and soil conditions. To address this gap, the study employs GeoT*SOL simulation to evaluate system performance, incorporating site-specific parameters such as soil thermal conductivity, heating demand profiles, and regional weather data. The results show that the GSHP system achieves a maximum seasonal performance factor (SPF) of 5.62 and an… More >

Wei Shi^1,2, Shusheng Xiong^1,2,3,*, Wei Li^2,3, Kai Meng⁴, Qingsheng Liu⁴

Energy Engineering, Vol.122, No.9, pp. 3507-3523, 2025, DOI:10.32604/ee.2025.065579 - 26 August 2025

Abstract In the realm of all-electric aircraft research, the integration of cathode-open proton exchange membrane fuel cells (PEMFC) with lithium batteries as a hybrid power source for small to medium-sized unmanned aerial vehicles (UAVs) has garnered significant attention. The PEMFC, serving as the primary energy supply, markedly extends the UAV’s operational endurance. However, due to payload limitations and spatial constraints in the airframe layout of UAVs, the stack requires customized adaptation. Moreover, the implementation of auxiliary systems to facilitate cold starts of the PEMFC under low-temperature conditions is not feasible. Relying solely on thermal insulation measures… More >

Alexey Melkikh^1,2, Sergey Rutin², Dmitrii V. Antonov³, Pavel Skripov^2,*

Frontiers in Heat and Mass Transfer, Vol.23, No.3, pp. 721-737, 2025, DOI:10.32604/fhmt.2025.066528 - 30 June 2025

Abstract The article considers a relaxation of the water/polypropylene glycol-425 solution with a lower critical solution temperature (LCST) following its pulsed superheating concerning liquid-liquid and liquid-vapor equilibrium lines, as well as the liquid-liquid spinodal. Superheating was performed using the pulsed heat generation method in a micro-sized wire probe. The main heating mode was the constant (over the pulse length) power mode. Characteristic heating rates ranged from 0.05 × 10⁵ to 2 × 10⁵ K/s, while the degree of superheating concerning the spinodal was up to 200 K. The temperature of spontaneous boiling-up and the amplitude of the… More > Graphic Abstract

Hammadi El Farissi^1,2,*, Anass Choukoud^1,2, Bouchaib Manoun^3,4, Mohamed El Massaoudi^5,6, Abdelmonaem Talhaoui²

Journal of Renewable Materials, Vol.13, No.6, pp. 1251-1266, 2025, DOI:10.32604/jrm.2025.02025-0004 - 23 June 2025

Abstract In light of the growing urgency to address environmental degradation and improve carbon sequestration strategies, this study rigorously investigates the potential of Cistus ladaniferus as a viable feedstock for biochar and activated carbon production. The influence of pyrolysis temperature, heating rate and particle size on biochar yield was systematically examined. The results demonstrate that increasing pyrolysis temperature and heating rate significantly reduces biochar yield, while particle size plays a crucial role in thermal degradation and biochar retention. To evaluate the structural and chemical properties of the materials, various characterization techniques were employed, including Fourier-transform infrared spectroscopy… More > Graphic Abstract

K. Sinivasan¹, N. Vishnu Ganesh^1,*, G. Hirankumar², M. Al-Mdallal Qasem^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1029-1049, 2025, DOI:10.32604/fdmp.2025.064503 - 30 May 2025

Abstract In this study, an analytical investigation is carried out to assess the impact of magnetic field-dependent (MFD) viscosity on the momentum and heat transfers inside the boundary layer of a Jeffrey fluid flowing over a horizontally elongating sheet, while taking into account the effects of ohmic dissipation. By applying similarity transformations, the original nonlinear governing equations with partial derivatives are transformed into ordinary differential equations. Analytical expressions for the momentum and energy equations are derived, incorporating the influence of MFD viscosity on the Jeffrey fluid. Then the impact of different parameters is assessed, including magnetic More >

Umi Nadrah Hussein¹, Najiyah Safwa Khashi’ie^1,*, Norihan Md Arifin², Ioan Pop³

Frontiers in Heat and Mass Transfer, Vol.23, No.2, pp. 383-395, 2025, DOI:10.32604/fhmt.2025.063023 - 25 April 2025

Abstract This study investigates the heat transfer and flow dynamics of a ternary hybrid nanofluid comprising alumina, copper, and silica/titania nanoparticles dispersed in water. The analysis considers the effects of suction, magnetic field, and Joule heating over a permeable shrinking disk. A mathematical model is developed and converted to a system of differential equations using similarity transformation which then, solved numerically using the bvp4c solver in Matlab software. The study introduces a novel comparative analysis of alumina-copper-silica and alumina-copper-titania nanofluids, revealing distinct thermal conductivity behaviors and identifying critical suction values necessary for flow stabilization. Dual solutions… More >

Tahir Naseem¹, Fateh Mebarek-Oudina^2,3,*, Hanumesh Vaidya⁴, Nagina Bibi⁵, Katta Ramesh^6,7, Sami Ullah Khan⁸

CMES-Computer Modeling in Engineering & Sciences, Vol.143, No.1, pp. 351-371, 2025, DOI:10.32604/cmes.2025.063196 - 11 April 2025

Abstract Maximizing the efficiency of thermal engineering equipment involves minimizing entropy generation, which arises from irreversible processes. This study examines thermal transport and entropy generation in viscous flow over a radially stretching disk, incorporating the effects of magnetohydrodynamics (MHD), viscous dissipation, Joule heating, and radiation. Similarity transformations are used to obtain dimensionless nonlinear ordinary differential equations (ODEs) from the governing coupled partial differential equations (PDEs). The converted equations are then solved by using the BVP4C solver in MATLAB. To validate the findings, the results are compared with previously published studies under fixed parameter conditions, demonstrating strong… More >

Xueli Wang¹, Yan Jia^2,*, Degong Zuo³

Energy Engineering, Vol.122, No.4, pp. 1603-1627, 2025, DOI:10.32604/ee.2025.062908 - 31 March 2025

Abstract The development of efficient and clean heating technologies is crucial for reducing carbon emissions in regions with severe cold regions. This research designs a novel two-stage phase change heat storage coupled solar-air source heat pump heating system structure that is specifically designed for such regions. The two-stage heat storage device in this heating system expands the storage temperature range of solar heat. The utilization of the two-stage heat storage device not only makes up for the instability of the solar heating system, but can also directly meet the building heating temperature, and can reduce the… More > Graphic Abstract