Article
Thermodynamics
Yanyan Xu, Weihua Cai, Yanqin Xue, Hong Qi, Qian Li
Summary: This study investigates the effects of ocean motions on the thermal performances of pulsating heat pipes (PHPs) and prepares surfactant-free functionalized multi-walled carbon nanotubes (f-MWCNTs) nanofluids with long-term stability. The results show that f-MWCNTs nanofluids exhibit the lowest thermal resistance, while ethanol-DI water mixed fluids perform better than ethanol-based f-MWCNTs nanofluids. Moreover, HFE-7100-DI water mixed fluids are more suitable for enhancing performance at lower heat loads.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Robert Dreiling, Sascha Zimmermann, Thinh Nguyen-Xuan, Peter Schreivogel, Francesca di Mare
Summary: This study presents a conduction-based approach for pseudo-steady heat transfer in pulsating heat pipes (PHPs) and calculates the internal thermal resistance using multi-fluid correlations. The simulation results of the external temperature field show good agreement with experimental data, and it is found that considering thermal spreading effects is crucial for interpreting the overall thermal resistance and designing optimal FP-PHPs.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Laxman Kumar Malla, Davis T. Vempeny, Hemanth Dileep, Praveen Dhanalakota, Pallab Sinha Mahapatra, Pankaj Srivastava, Arvind Pattamatta
Summary: This study investigates the effect of thermal conductivity and binary mixtures on the thermal performance of a flat plate pulsating heat pipe (FPPHP). The results show that ethanol-water mixtures in an ideal ratio offer smaller thermal resistances, larger oscillations, and fewer drying-out occurrences compared to pure water or ethanol. The oscillation of the working fluid mainly influences the thermal resistance in the steel FPPHP, while the spreading resistance through the plate primarily affects the thermal resistance in the copper FPPHP. The findings of this study are valuable for designing suitable FPPHPs for different applications.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
Burak Markal, Ramazan Varol
Summary: A comprehensive experiment on a flat plate closed loop pulsating heat pipe charged with ternary mixtures showed that an intermediate filling ratio of 50% resulted in optimum performance, and mixtures with higher pentane or methanol content exhibited better thermal characteristics compared to pure fluids. However, heat pipes charged with ternary mixtures are highly dependent on gravity and cannot operate in a horizontal position. The presence of a rewetting phenomenon in heat pipes charged with ternary mixtures enhances thermal performance.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Review
Thermodynamics
Vincent Ayel, Maksym Slobodeniuk, Remi Bertossi, Cyril Romestant, Yves Bertin
Summary: Thermal management of modern micro- and high-power electronic systems is becoming increasingly challenging due to trends in miniaturization and heat generation. Pulsating heat pipes have attracted growing interest as passive heat transfer devices with high reliability and diverse applications, distinct from traditional heat pipes. Their manufacturing methods and internal structures differ from classical heat pipes, resulting in unique thermo-hydrodynamic behaviors.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Yanyan Xu, Yanqin Xue, Weihua Cai, Hong Qi, Qian Li
Summary: This paper studies the performances of 3D-printed flat-plate PHPs and CNC machined flat-plate PHPs in waste heat recovery. The study finds that the performance of the heat recovery system with CNC machined flat-plate PHP is generally better than that with 3D-printed flat-plate PHP. The system's performance can be improved by using slotted fins, increasing the condenser section length, and increasing the number of flat-plate PHPs.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Ali Ahmed Alqahtani, Stuart Edwardson, Marco Marengo, Volfango Bertola
Summary: The heat transfer performance of a flat-plate, flexible polypropylene pulsating heat pipe (PHP) was experimentally evaluated. The bending angle and the reciprocal positions of the heat sink and source were found to have minimal effect on the thermal performance, but may affect the start-up of the PHP.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Sriram Chidambaranathan, Swaminathan M. Rangaswamy
Summary: The study investigated the heat transfer performance of a pulsating heat pipe using high carbon alcohols self-rewetting fluids, showing the significant role of latent heat of vaporization and unique behavior of self-rewetting fluids due to the inverse Marangoni effect, leading to lower thermal resistance and higher heat transfer coefficients, especially in the dilute aqueous solution of 1-octanol.
Article
Thermodynamics
K. Sefiane, R. E. Christy, G. Duursma, J. C. Ebeling, T. Seewald, S. Harmand
Summary: There is growing interest in the use of self-rewetting mixtures for micro-scale heat transfer systems. These fluids, with increased surface tension at higher temperatures, are expected to provide enhanced evaporative cooling performance. However, the mechanism behind these improvements is not fully understood. Through studying the flow within evaporating drops of 1pentanol-water mixtures, researchers have observed three stages in the evaporation process. These stages involve the formation of a toroidal vortex, pulsating vortex, and radial outward flow.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Mauro Mameli, Giorgio Besagni, Pradeep K. Bansal, Christos N. Markides
Summary: Pulsating heat pipes (PHPs) have emerged as an innovative and effective passive two-phase heat transfer system since the early 1990s, with good performance and versatility. However, the complex thermohydraulic behavior of PHPs remains a challenge for designers. The technology is being considered for various industrial applications such as electronic cooling, cryogenic temperatures, and space environments.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Laxman Kumar Malla, Praveen Dhanalakota, PallabSinha Mahapatra, Arvind Pattamatta
Summary: The thermal performance and internal flow regimes of a closed-loop flat plate pulsating heat pipe (FPPHP) are experimentally investigated using ethanol-water mixtures as working fluids. The results show that the mixtures with increased ethanol content perform better in terms of thermal resistance and slug-plug flow oscillations. The effect of different condenser cooling modes on the thermal performance is also reported.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Burak Markal, Ayse Candan Candere, Mete Avci, Orhan Aydin
Summary: Experimental investigation on the effect of double cross sectional ratio on performance characteristics of pulsating heat pipes shows that novel gradually constricted geometry boosts flow circulation and maintains stable performance. The newly designed pulsating heat pipe demonstrates better thermal performance than the conventional design.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Gyuchang Kim, Seungyeop Baek, Wontak Choi, Ajeong Lee, Seunghyeon Lee, Hyomin Jeong, Yonmo Sung
Summary: This study found that 0.5 wt% Al2O3 nanofluids exhibit good dispersibility, while the addition of Al2O3 increases the fluid's surface tension and thermal conductivity.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Yanyan Xu, Yanqin Xue, Weihua Cai, Hong Qi, Qian Li
Summary: Waste heat recovery for thermoelectric power generation is crucial for achieving carbon peak-ing and carbon neutrality goals. This study comparatively investigates the performance of flat-plate pulsating heat pipe (PHP) coupled with thermoelectric generators (TEGs) under different heating conditions. The type, number, layer number, connection mode, and installation mode of TEGs are analyzed for their effects on the coupling system. The results show that the optimal type of TEGs varies under different conditions. The study also reveals the negligible effects of connection mode, installation mode, and cooling water flow rate on the maximum output power of the coupling system.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Kimihide Odagiri, Kieran Wolk, Stefano Cappucci, Stefano Morellina, Scott Roberts, Andre Pate, Benjamin Furst, Eric Sunada, Takuro Daimaru
Summary: This paper presents a three-dimensional heat transfer analysis of a flat-plate oscillating heat pipe (OHP) and reveals the combined effect of thermo-hydraulic phenomena and thermal diffusion in the OHP structure. Surface roughness and liquid film thickness in the channel were found to have an impact on the operating temperature distribution.
APPLIED THERMAL ENGINEERING
(2021)
Article
Nuclear Science & Technology
Maneesh Punetha, Mahesh Kumar Yadav, Samyak Jain, Sameer Khandekar, Pavan K. Sharma
Summary: The paper describes the detailed thermal and mechanical design procedure of a Controlled Flow (CONFLO) facility and a Thermal Hydraulic test facility for Containment (THYCON) to investigate post-severe accident scenarios in Nuclear Power Plant containments. The experimental data generated from the setups is used to develop design equations and suggest locations for essential safety equipment in containments. The thermal-hydraulic experiments suggest that condensation heat transfer inside NPP containments is primarily governed by several interlinked phenomena.
PROGRESS IN NUCLEAR ENERGY
(2021)
Article
Thermodynamics
Prem Kumar, Mayur Gachake, Sameer Khandekar
Summary: The study focuses on reducing heat leak in loop heat pipes (LHP) by manipulating the properties of the copper wick, leading to improved thermal performance. It was found that the oxidized copper wick performs better thermally than the pure copper wick, attributed to the lower thermal conductivity of the oxidized porous wick reducing heat leak.
APPLIED THERMAL ENGINEERING
(2022)
Review
Materials Science, Multidisciplinary
Madhusree Kole, Sameer Khandekar
Summary: Ferrofluids are stable colloidal suspensions of nanometric sized ferromagnetic particles in conventional basefluids, with their ferromagnetic property changed to superparamagnetism. They have diverse applications due to their unique thermophysical properties, ranging from computer hard discs to bio-medical applications.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Thermodynamics
Ram Krishna Shah, Sameer Khandekar
Summary: This study explores the augmentation of two-phase heat transfer through magnetic manipulation of non-boiling Taylor bubble flow. The smaller bubbles and unit-cells generated by magnetic manipulation result in reduced void fraction and increased heat exchange efficiency. This provides an effective alternative for on-demand augmentation in two-phase heat transfer in low Reynolds number flows.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Madhusree Kole, Ram Krishna Shah, Sameer Khandekar
Summary: The existing thermal management strategies for mini-/micro scale electronic devices have reached their limits, calling for the development of innovative heat transfer methods. This study investigates a novel heat transfer configuration involving convective heat transfer of two-phase air-ferrofluid Taylor bubble flow in a square mini channel at low Reynolds number. The results show significant improvement in heat transfer coefficient.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Physical
Ram Krishna Shah, Sameer Khandekar
Summary: This study demonstrates that the thermal transport characteristics of bubble-slug flows can be enhanced and controlled by using ferro-nanocolloids or ferrofluids as the primary liquid phase. The flow morphology can be altered through an externally applied magnetic field, resulting in the generation of smaller bubble-slug units. The movement of these smaller units disrupts the flow boundary and interfacial regions, creating additional recirculation regions and enhancing convective transport. Heat transfer augmentation of up to 80% is observed, depending on the gas fraction of the flow. Smaller bubble-slug units are found to be superior for achieving higher heat transfer coefficients.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Thermodynamics
Ankush Kumar Jaiswal, Sameer Khandekar
Summary: This study investigates the heat transfer during the impact of two liquid droplets and finds that the impact velocity and droplet size have an effect on heat transfer. By comparing it with the impact of a single droplet, an appropriate velocity scale range is determined to accurately predict the heat transfer during droplet impact.
NUMERICAL HEAT TRANSFER PART B-FUNDAMENTALS
(2023)
Article
Thermodynamics
Manish Bhendura, K. Muralidhar, Sameer Khandekar
Summary: Evaporation is an important step in clean water production technologies, and this study uses imaging and modeling techniques to investigate the buoyant flow in water during the evaporation process. The evaporation rate is determined using an ab initio model, and the results are compared with other models and experiments, showing close agreement with the experimental results.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Abhishek Karmakar, Max L. Olender, David Marlevi, Evan Shlofmitz, Richard A. Shlofmitz, Elazer R. Edelman, Farhad R. Nezami
Summary: This study presents a fully automated, robust, nonrigid registration method for coregistering multimodal tomographic vascular image datasets. The registration is carried out using luminal annotation as the sole alignment feature. The method achieves low registration errors and shows potential wide-ranging applicability.
JOURNAL OF MEDICAL IMAGING
(2022)
Article
Thermodynamics
Gopinath Sahu, Sameer Khandekar, K. Muralidhar
Summary: This study compares liquid jet and spray over plain and pillared copper surfaces with different coolant flow rates. It is observed that strong liquid splattering occurs over the pillared surfaces at higher coolant flow rates. The effect of splattering on heat transfer performance is compared for different heat flux conditions, and it is found that spray cooling shows superior heat transfer enhancement over a liquid jet for a pillared surface, delaying the critical heat flux limit.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Chemistry, Multidisciplinary
Sohom Goswami, Ravi M. Sidhpuria, Sameer Khandekar
Summary: The severe water scarcity caused by growing population and rapid urbanization has led to the development of novel techniques for fog collection. This study focuses on the development of an artificial fog-generating system and the investigation of how the growth of collected fog droplets on fiber surfaces affects fog collection efficiency. The results show that the effective shade coefficient and the shape of droplets growing on harp fibers play a significant role in fog flow aerodynamics and collection efficiency.
Article
Thermodynamics
Gopinath Sahu, Sameer Khandekar, K. Muralidhar
Summary: This study investigates the thermal characteristics of spray cooling on high-power LED modules. Experimental and numerical approaches are used to analyze the temperature distribution and heat removal capacity within the LED assembly. The results demonstrate the effectiveness of spray cooling design in reducing the junction temperature of LED modules.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Thermodynamics
Prem Kumar, Gopinath Sahu, Debartha Chatterjee, Sameer Khandekar
Summary: This study demonstrates the feasibility of using a copper Loop Heat Pipe (LHP) as a thermal management solution for high-power LED modules. Through experiments and computational simulations, the results show that the copper-methanol LHP design can effectively dissipate the heat generated by the module and maintain the junction temperature within a reliable range.
APPLIED THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Yunxia Ma, Fei Liu, Honggang Pan, Hongjian Zhang, Shuxia Yan, Ailing Zhang
Summary: This paper proposes a dynamically tunable and switchable perfect infrared absorber that exhibits excellent electrical regulation performance and high absorptance. The absorption mechanism is explained using a multiple interference model, and it is proven to be polarization insensitive.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
F. J. dos Santos, G. S. M. Martins, M. Strobel, L. Beckedorff, K. V. de Paiva, J. L. G. Oliveira
Summary: This study investigates the effects of inlet conditions and plate's features on the thermal-flow performance of a gasket plate heat exchanger (GPHE) and assesses the impact of a modified tightening distance on its performance. No systematic study on the combined effects of inlet conditions and assembly accuracy on GPHE performance has been conducted before.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Alok K. Ray, Dibakar Rakshit, K. Ravi Kumar, Hal Gurgenci
Summary: The low thermal conductivity of phase change materials limits the heat transfer rate and application of latent heat storage systems. This numerical study examines the impact of two passive heat transfer enhancement techniques on the thermal performance of a latent heat storage system. The results show that the orientation and position of the heat transfer fluid tube have significant effects on the charging duration, while the discharging duration remains unchanged. The combined effect of orientation and eccentricity reduces the charging duration, but increases the discharging duration compared to the concentric domain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yalu Han, Yanlong Wang, Chenyang Liu, Xinmin Hu, Yin An, Zhengcai Li, Jiaxun Jiang, Lizhi Du
Summary: This paper investigates the calculation method of thermal conductivity in NAPLs-contaminated soils. By establishing NAPLs-contaminated soil models and using the Lattice Boltzmann Method (LBM) for calculation, an optimized three-dimensional model with high computational accuracy and efficiency is obtained. The study also finds that saturation and Nz parameters have a significant impact on calculation time, while the thermal conductivity of the two-dimensional model is more sensitive to anisotropy. The influence of porosity and NAPLs content on thermal conductivity should be considered during in-situ thermal desorption.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin
Summary: For the first time, large-eddy simulations (LES) of the near-field region of large-scale fire plumes were performed using a pressure-based Lattice Boltzmann method (LBM) with low-Mach number approximation. The simulations showed quantitative agreement with experimental data and were consistent with previously-published numerical studies. The study demonstrated the computational efficiency of the proposed LBM solver in tackling fire-induced flows, suggesting LBMs as a good alternative candidate for modeling fire-related problems.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weixin Zhang, Yehang Xie, Yuqiang Ding, Zhao Liu, Zhenping Feng
Summary: This study investigated the impact of upstream slot leakage on the endwall film cooling characteristics of turbine blades. Pressure Sensitive Paint (PSP) technology was used to measure the film cooling characteristics, and numerical analysis was conducted to evaluate the aerodynamic performance. It was found that increasing the mass flow ratio of the upstream slot enhanced film cooling, decreased aerodynamic losses, and reduced the strength of passage vortex. However, reducing the distance between the slot and the blade leading edge only enhanced film cooling without affecting the leakage coverage area.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rui Zhang, Zhen-lei Li, Yan-sheng Zhang, Dong Chen, Guo Yuan
Summary: This study discusses the heat transfer behavior of different jet forms on steel tubes. The results show that the annular jet performs better in terms of cooling intensity and uniformity. The cooling performances of the two jet forms are similar when the steel tube size is small. Therefore, the planar jet can be considered for smaller diameters due to its simplicity, low cost, and convenience in application.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
A. R. Khoei, A. M. Orvati Movaffagh, A. Rezaei Sameti
Summary: This paper presents a comprehensive study on the thermo-mechanical characteristics of oxide-coated aluminum nano-powder. It is found that the thermal conductivity of oxide-coated aluminum nano-powder is significantly lower than that of the bulk aluminum, and it is affected by the density and temperature.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yanjin Wang, Jintao Xiong, Lingyu Chen, Zhihai Lv, Qian Wang
Summary: A solar radiation transfer model for spray cooling double skin facade (SC-DSF) is proposed in this study. The model is validated by experimental results and various influence factors are analyzed. The effectiveness of adjusting droplet coverage rate and size is also evaluated.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Bostjan Zajec, Blaz Mikuz, Anil Kumar Basavaraj, Marko Matkovic, Matej Tekavcic, Martin Draksler, Leon Cizelj, Bostjan Koncar
Summary: We have developed an advanced experimental setup to investigate flow and heat transfer in an annular channel. The setup allows heat transfer measurements and flow visualization using a temperature-controlled inner tube. Measurements can be conducted in both single-phase and two-phase flow regimes. The setup ensures a uniform velocity field in the annular channel using specially designed inlet and outlet headers. The inner copper tube is heated by water and contains turbulators for enhanced heat transfer and thermocouples for temperature measurement. A three-dimensional conjugate heat transfer CFD model has been developed and validated to accurately estimate heat losses in the setup. This study demonstrates the importance of numerical simulations in improving the interpretation of complex experimental results.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weijie Chen, Ke Wang, Yongqing Wang, Shantung Tu, Zunchao Liu, Huijuan Su
Summary: In this study, a novel gradient porosity transpiration cooling plate structure (GP-TCPS) is proposed to alleviate heat transfer deterioration caused by non-uniform temperature distribution in transpiration cooling plate structure (TCPS). Computational fluid dynamics (CFD) and response surface method (RSM) were used for qualitative and quantitative analysis of the flow and heat transfer of GP-TCPS. The optimized structure of GP-TCPS significantly improves temperature uniformity, injection pressure, and average cooling efficiency compared to traditional TCPS.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
R. Essam, A. Elsaid, W. K. Zahra
Summary: This study presents a novel bioheat model for simulating heat transfer in skin tissue. The model offers an improved representation of thermal dynamics in the skin and has been validated using numerical solutions and experimental measurements. The study highlights the importance of incorporating vascular inlet parameters and thermal relaxation effects in the thermal profile, and suggests potential applications in thermal therapy and wound healing.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Dongbo Shi, Tao Xu, Zifeng Chen, Di Zhang, Yonghui Xie
Summary: The cooling structure design of turbine blades is crucial for the safety and reliability of the gas turbine set. This research investigates different arrangement schemes, including dimple/protrusion arrangements, to enhance the cooling performance. The results show that the arrangement scheme with both passes arranged by dimples has the best comprehensive thermal performance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Emrehan Guersoy, Hayati Kadir Pazarlioglu, Mehmet Guerdal, Engin Gedik, Kamil Arslan
Summary: The thermo-hydraulic performance of Al2O3/H2O nanofluid with different nanoparticle shapes flowing in a sudden expansion tube with variable sudden expansion inclination angles and elliptical dimpled fins with different diameters were numerically investigated. The results showed that the nanoparticle shapes, sudden expansion inclination angles, and elliptical dimpled fin have significant impact on the thermo-hydraulic performance. This study reveals the novelty and importance of these factors in the research.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rukun Hu, Xinyu Huang, Xinyu Gao, Liu Lu, Xiaohu Yang, Bengt Sund
Summary: This study examines the impact of applying bottom cross-cut on PCM's spatial distribution in a horizontal LHTES unit using numerical simulation. The findings show that bottom cross-cut can improve the heat storage rate and natural convection heat transfer gain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
