Article
Engineering, Mechanical
Long Zeng, Daxiang Deng, Ningbo Zhong, Guisen Zheng
Summary: A unique microchannel heat sink design with inline and staggered open-ring pin fins was developed for high heat flux devices. The open-ring pin fins induced flow separations and convergences, leading to enhanced heat transfer performance. The staggered configuration showed slightly better heat transfer performance than the inline configuration, making it more favorable for heat dissipation in high heat flux devices.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Chemistry, Physical
Yunfei Yan, Chenghua Zhang, Jie Gao, Kaiming Shen, Wei Gao
Summary: This study focuses on optimizing the structure of micro combustors to improve energy output performance of MTPV systems. Results show that both MCIPF and MCEPF have higher combustion efficiency compared to the conventional MCC, with MCIPF having the highest external wall temperature under different conditions and MCEPF maintaining the best temperature uniformity. The application of high thermal conductivity materials like Aluminum, Red Copper, and Silicon Carbide can enhance external wall temperature and temperature uniformity, providing a new design method for improved heat transfer in micro combustors.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Thermodynamics
Djamel Sahel, Lahcene Bellahcene, Aissa Yousfi, Abdussamet Subasi
Summary: The study investigated the hydrothermal performance of a heat sink with hemispherical pin fins under fully turbulent flow conditions and optimized the fin configuration. Through the perforation technique, the hydrothermal performance of the heat sink was enhanced significantly.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Zhijian Duan, Gongnan Xie, Bo Yu, Puhang Jin
Summary: The study focuses on designing optimized structures for liquid-cooled microchannel heat sinks with different pin-fin arrays using the topology optimization method for better performance. The goal is to minimize flow energy dissipation and average temperature of the bottom surface to facilitate more efficient design of microchannel heat sinks for electronic chips' cooling.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Review
Green & Sustainable Science & Technology
Abdolvahab Ravanji, Ann Lee, Javad Mohammadpour, Shaokoon Cheng
Summary: Effective thermal management is crucial for device performance, product longevity, energy saving, environmental protection, and avoiding thermal failures. Pin fins are widely used for passive cooling and their optimization plays a significant role in improving flow structure, heat transfer, and minimizing pressure drops. This study critically reviews the literature on pin fins, explores their thermohydraulic performance, and provides valuable insights for the design of efficient cooling systems.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Thermodynamics
M. P. Vasilev, R. Sh Abiev, R. Kumar
Summary: A computational simulation was conducted to compare the performance of different types of microchannel heat sink models equipped with circular pin fins, finding that thermal resistance largely depends on pin height and the optimal pin placement step also varies for different pin heights.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Engineering, Chemical
Injamamul Haque, Tabish Alam, Jagmohan Yadav, Naveen Kumar Gupta, Md Irfanul Haque Siddiqui, Tauseef Uddin Siddiqui, Naushad Ali, Shivam Srivastava, Anil Singh Yadav, Abhishek Sharma, Rohit Khargotra, Amit Kumar Thakur
Summary: Higher density heat flux causes damage to electronic components, so cooling them is crucial for safe operation and longer lifespan. In this study, lozenge-shaped pin-fins were designed and used in microchannel heat sinks to achieve better cooling performance. The results showed that introducing lozenge-shaped pin-fins greatly improved heat transmission, with the best performance observed at an aspect ratio of 1.00.
INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING
(2023)
Article
Chemistry, Analytical
Guo-Fu Xie, Lei Zhao, Yuan-Yuan Dong, Yu-Guang Li, Shang-Lin Zhang, Chen Yang
Summary: The effects of inclined angle and arrangement method on flow field and temperature field of microchannel heat sinks were studied. The best thermal performance was achieved in microchannel heat sinks with in-lined fins at an inclined angle of 30 degrees.
Article
Thermodynamics
Lei Liu, Lingmin Yu, Bo Yuan, Bin Liu, Jinjia Wei
Summary: ZnO nanorods were synthesized on micro-pin-fins to enhance flow boiling heat transfer. The micro/nano hierarchical surface (PF + NR) was characterized for morphology, chemical composition, and wickability. Compared with PF, NR, and S surfaces, PF + NR showed significantly improved boiling performance, with a 63%, 76%, and 158% increase in the maximum boiling heat transfer coefficient, respectively. The comprehensive improvement in heat transfer performance can be attributed to the cooperation of structures in different scales, providing sufficient nucleation sites and enhancing liquid replenishment capacity.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Muhammed Emin Polat, Furkan Ulger, Sertac Cadirci
Summary: This study numerically investigated laminar, steady-state microchannel flow and conjugate heat transfer in a microchannel heat sink with micro pin-fins. Through optimizing the arrangement of micro pin-fins, the study obtained optimized heat performance, with diamond-shaped pin-fins significantly enhancing heat transfer at an increased pressure drop ratio.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Yuhui Pan, Rui Zhao, Yongle Nian, Wenlong Cheng
Summary: The heat transfer performance of the pin-fin manifold microchannel is better than that of the rectangular manifold microchannel at the same mass flux, although the pressure drop is higher. Additionally, at the same pressure drop, the heat transfer performance of the pin-fin manifold microchannel is still superior to that of the rectangular manifold microchannel.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Chunquan Li, Xuebin Li, Hongyan Huang, Yuanhao Zheng
Summary: A new microchannel heat sink with embedded modules with ribs and pin-fins is proposed for efficient microchannel heat dissipation. Strategies such as microchannel cooling within low-temperature co-fired ceramic substrates, embedding modules in the substrate, and creating ribs and pin-fins are employed to enhance heat transfer. The study investigates the effects of relative rib height, relative pin-fin height, and relative number of auxiliary channels on heat transfer performance, temperature uniformity, and pressure drop. The performance of the proposed design is compared to other similar designs, showing significant improvements in heat transfer and temperature uniformity with a slight increase in pressure drop.
APPLIED THERMAL ENGINEERING
(2023)
Article
Mechanics
Kun-Da Wu, Huei Chu Weng
Summary: The purpose of this study is to investigate the impact of pin-fin NACA airfoil on the heat transfer performance of a single open microchannel heat sink. The flow patterns generated by the periodically arranged pin fins with an attack angle significantly affect the heat dissipation ability. Increasing the attack angle and Reynolds number can further improve the heat dissipation ability. Among the airfoils considered, the asymmetric airfoil NACA6412 shows the best overall thermal performance with a significant increase in Nusselt number and thermal performance factor compared to the symmetrical NACA0012 case.
JOURNAL OF MECHANICS
(2023)
Article
Thermodynamics
Manish Kumar Mohit, Rajesh Gupta
Summary: This paper investigates the thermal and flow characteristics in a microchannel with pin fins through numerical simulation. The results show that heat transfer increases significantly with an increase in fin height and Reynolds number. However, the influence of different fin heights on heat transfer differs after a certain Reynolds number.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Ali Mohammad Ranjbar, Zeinab Pouransari, Majid Siavashi
Summary: This study investigated the turbulent forced convection heat transfer of air in the presence of porous pin fins for cooling thermal parts of devices. Five fin structures, two different fin arrangements, and three various Darcy numbers were examined to analyze the effects of these parameters on the heat sink performance. It was concluded that the decreasing-aligned pin fin configuration with the highest Darcy number provided the best performance among the studied cases.
APPLIED THERMAL ENGINEERING
(2021)
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)