Semnan University PressJournal of Heat and Mass Transfer Research2345-508X13420261201Advances in Subcooling Techniques for Transcritical CO₂ Refrigeration Systems: A Comprehensive Review3874121056310.22075/jhmtr.2026.39481.1865ENSaif NawazAhmadResearch and Development Cell, Cool-Max Innovation, Bhiwadi, Rajasthan, India0000-0001-7936-6096NitinKumarDepartment of Mechanical Engineering, RKGIT Ghaziabad, Uttar Pradesh, IndiaRajnishKumarDepartment of Aeronautical Engineering, NCE Chandi, Bihar, IndiaAdil NawazAhmadDepartment of Civil Engineering, Aliah University Kolkata, IndiaJournal Article20251023Transcritical CO₂ refrigeration systems are increasingly adopted as low-GWP alternatives; however, their performance deteriorates due to high gas cooler pressures and large throttling losses. Subcooling the refrigerant before expansion is a key thermodynamic solution to mitigate these losses, yet a comprehensive and updated synthesis that directly compares the performance and applicability of diverse subcooling techniques within a unified framework is lacking. This review addresses that gap by providing a structured, critical analysis of both internal and external subcooling methods, including internal heat exchangers (IHX), ejector- and expander-assisted systems, and mechanical and thermoelectric subcoolers. The consolidated findings indicate that for high-ambient conditions, mechanical subcooling consistently emerges as the most effective approach, offering substantial COP improvements (20-40%) and in the case of DMS, significant discharge pressure reduction. This review further examines integration challenges, advanced control strategies, and emerging hybrid and renewable-assisted systems, offering valuable insights for researchers and designers aiming to enhance the sustainability and performance of next-generation CO₂ refrigeration technologies.https://jhmtr.semnan.ac.ir/article_10563_1f2b8183cd1e469ad3a7ad1eadce49d1.pdfSemnan University PressJournal of Heat and Mass Transfer Research2345-508X13420261201Innovative Parametric Study on Water Extraction from Atmospheric Moisture in a Sealed Chamber via Vapor-Compression Refrigerationمطالعه پارامتریک ابتکاری در استخراج آب از رطوبت جو در یک محفظه بسته از طریق تبرید تراکمی4134221043210.22075/jhmtr.2026.36305.1662ENSeyed ErfanSokhangouyFaculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, IranMostafaVarmazyarFaculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, Iran0000-0003-4941-8304Journal Article20241220In this study, a cycle for water production from air trapped in a closed chamber is simulated and analyzed. The cycle comprises two sections: humid air and refrigerant. Humid air flows over evaporator coils, condensing water vapor into droplets. Various parameters affecting the cycle's performance, including the temperature and flow rate of incoming humid air, and the refrigerant temperature, are investigated. Through numerical modeling and parametric analysis, it is found that lower refrigerant temperatures in the evaporator significantly increase water production, especially at temperatures below 5°C. Furthermore, increasing the humid air flow rate up to 0.05 kg/s enhances dehumidification, but further increases beyond this rate reduce dehumidification as the cooling capacity is primarily used to lower air temperature. Additionally, it is observed that higher inlet air temperatures initially increase water production, with optimal flow rates varying based on temperature conditions. The ratio of latent heat to compressor power consumption improves with higher flow rates up to 0.05 kg/s, after which efficiency decreases. While the Coefficient of Performance (COP) improves with increased air flow rates, higher evaporator coil temperatures lead to reduced moisture extraction. These findings provide valuable insights for optimizing water production cycles, offering strategies to enhance efficiency for industrial and environmental applications.https://jhmtr.semnan.ac.ir/article_10432_3181d59d19e76e902666df5c7821259a.pdfSemnan University PressJournal of Heat and Mass Transfer Research2345-508X13420261201Numerical Study of the Impact of Peritoneal Fluid and Its Convection on Magnetic Nanoparticle Hyperthermia in the Treatment of Peritoneal Metastasisمطالعه عددی تاثیر مایع صفاقی و همرفت آن بر گرمادرمانی نانوذرات مغناطیسی در درمان متاستاز صفاقی4234381060510.22075/jhmtr.2026.37513.1732ENMohadeseRanjbaranDepartment of Physics, Faculty of Science, Bu-Ali Sina University, Hamadan 65174, Iran0009-0007-0545-5660Mohammad HosseinTavakoliDepartment of Physics, Faculty of Science, Bu-Ali Sina University, Hamadan 65174, Iran0000-0002-4829-8913ZahraKeshtpour AmlashiCancer Research Center, Hamadan University of Medical Sciences, Hamadan 65178, Iran0000-0001-7126-0393SafooraNikzadDepartment of Medical Physics, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan 65178, Iran0000-0001-5156-4074Journal Article20250427This study evaluates magnetic nanoparticle hyperthermia for treating peritoneal metastasis, focusing on the effect of ascitic fluid and convection on tumor heating and healthy tissue. Magnetic nanoparticles (MNPs) were applied to raise tumor temperature to 42–46°C under an alternating magnetic field. Finite element simulations were used to calculate magnetic field distribution (Maxwell’s equations), heat generated by MNPs (Rosensweig model), temperature in the tumor and surrounding solid tissue (Pennes bioheat equation), and fluid temperature and convection in the peritoneal cavity (Navier–Stokes equations). Induction heating in the tumor was unaffected by ascitic fluid, though overall heat in the peritoneal cavity increased. Heat generated by MNPs was lowest at the tumor center and highest near the surface, with ascitic fluid enhancing heat production. Tumor temperature reached 45–46°C without ascitic fluid but decreased to 43–44°C when convection was present. Healthy tissue temperature remained below 44.2°C in both scenarios. Convective cooling in the fluid was the dominant factor influencing temperature distribution, causing non-uniform heating within the tumor. Conclusion: Magnetic nanoparticle hyperthermia effectively targets tumor tissue while protecting healthy tissue. The presence of ascitic fluid significantly alters temperature distribution through convection, highlighting the importance of considering fluid dynamics in treatment planning.https://jhmtr.semnan.ac.ir/article_10605_9306b519cdfe94d2c8fc0e733b0b8842.pdfSemnan University PressJournal of Heat and Mass Transfer Research2345-508X13420261201Evaluation of Mass Transfer Characteristics of Reverse Osmosis Desalination Process Based on the Spiegler-Kedem-Katchalsky Modelارزیابی ویژگیهای انتقال جرم فرآیند نمکزدایی اسمز معکوس بر اساس SPIEGLER-KEDEM-KATCHALSKY439447994310.22075/jhmtr.2025.33417.1527ENDnya SharifMohammedKurdistantechnical Institute, Kurdistan Region, IraqIbtisamKamalPetroleum Engineering Department, College of Science and Technology, University of Basrah, Basrah, IraqAbdulsamadAbdulhameedSiemens Energy, Department of Operation, Khormala Power Plant, Erbil, IraqJournal Article20240314In previous work, the reverse osmosis (RO) process was evaluated based on the potential synergy of Process Design and response surface methodology (RSM) methodologies, and the effects of membrane age, percentage recovery, concentrations of salts, pH, temperature, and pressure of feed water and the rejected brine concentration were optimized and modeled. The current work includes the determination of phenomenological parameters of mass transfer for RO membrane systems using the Spiegler-Kedem-Katchalsky model. The mass transfer coefficient and membrane permeability for salts were determined as a function of temperature and percentage recovery. The calculations of mass transfer parameters were based on a reference RO membrane (ESPA4-LD-4040), a three stage RO process, a 3-year membrane age with 95% and 85% recovery, a permeate flow 20 m3/h, pH 7, a constant feed TDS of 800 mg/l, constant pump pressure for feed water of 15 bar, and feed-water temperatures of 4, 8.2, 25, 30, and 42oC. The results showed that when the temperature increases from 4°C to 42°C, the mass transfer coefficient increases by 35.44% for 95% recovery, and 83.97% for 85% recovery, respectively. A general mathematical model describing the relationship between the mass transfer coefficient and feed water temperature, water permeability, and salt permeability was developed. The Spiegler-Kedem-Katchalsky model proved its capability for membrane performance evaluation through the determination and correlation of the phenomenological parameters of mass transfer for the membrane system.https://jhmtr.semnan.ac.ir/article_9943_5837e05c0213dc1617e409543331442c.pdf