Article
Thermodynamics
Dandan Qiu, Lei Luo, Zhiqi Zhao, Songtao Wang, Zhongqi Wang, Bengt Sunden
Summary: Numerical simulations were conducted to investigate the effects of pin-fin arrangement and jet Reynolds number on heat transfer enhancement and flow characteristics. The results showed that the appearance of pin-fin was beneficial in heat transfer enhancement and uniformity, with the 35 degrees pin-fin arrangement angle achieving the highest overall Nusselt number.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
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
Han Yan, Lei Luo, Junfeng Zhang, Wei Du, Dan Huang, Songtao Wang
Summary: This study investigates the influences of dimple location on the heat transfer performance of a pin fin-dimpled channel with upright/curved/inclined pin fins under both stationary and rotating conditions. The results show that the pin fin plays a dominant role in heat transfer performance compared to the dimple. The heat transfer performance is critically affected by the interaction of the longitudinal secondary flow and jet-like flow. The dimple location significantly affects the formation, development, and impingement of jet-like flow and longitudinal secondary flow. The dimple located at the behind position exhibits the poorest heat transfer enhancement. The originality of this study lies in evaluating the heat transfer performance of the combined cooling structure of dimple and pin fin, providing valuable insights for turbine blade design.
INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
(2022)
Article
Thermodynamics
Zhenxing Zhao, Bin Hu, Jing He, Mei Lin, Hanbing Ke
Summary: In order to ensure the normal operation of electronic devices, it is crucial to design an efficient cooling system. This study analyzed the two-phase flow boiling performance of staggered pin finned channels using the Mixture multiphase model. The influence of different fin cross-section shapes (circular, triangular, diamond, and pentagonal) on flow boiling heat transfer, pressure drop, and temperature uniformity under different heat flux conditions were compared. The results showed that the pentagonal finned channel is the most effective in terms of heat transfer coefficient, pressure drop, and temperature uniformity.
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Ahmet Ali Sertkaya, Mukaddes Ozdemir, Eyub Canli
Summary: In this study, pin fin and plate heat sinks were investigated in terms of natural convection and radiation heat transfer by experimental means. It was found that increasing the number of pin fins up to a threshold can improve thermal performance, but beyond that threshold, the thermal convection coefficient decreases significantly. Increasing the number of pin fins partly compensates the reduction in thermal convection coefficient by increasing the surface area up to a certain level.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Thermodynamics
Mingrui Wang, Huiren Zhu, Cunliang Liu, Tao Guo, Zhuang Wu, Na Li
Summary: Conjugate heat transfer was employed to enhance the cooling performance of turbine guided vanes in real working conditions. By improving internal and external cooling systems, overall cooling effectiveness was increased with limited influence on coolant consumption and cascade pressure loss. The study found that the internal cooling enhancements improved heat transfer and reduced coolant consumption, while changes to external film cooling had a detrimental effect. Further improvements in external cooling, such as through dimples and protrusions, led to increased film cooling effectiveness and heat transfer, albeit with higher coolant consumption. The research concluded that combining impingement/effusion cooling with ribs and protrusions resulted in the highest overall cooling effectiveness, with limited changes in coolant consumption and cascade pressure loss factors.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Thermodynamics
Zixing Wang, Hao Ding, Le Lei, Nan Li, Wenquan Tao
Summary: This paper presents the construction process of the enhanced plate, the heat transfer and fluid flow characteristics, and the domain decomposition method for AHU performance estimation. The AHU heat exchanger 3D model is built using plate modeling and assembly. Different types of dimples are added to the flat plate to enhance heat transfer. The performance of the enhanced channels and the recommended heat exchanger design are evaluated based on the Nusselt number, friction factors, heat exchange rate, and flow loss power.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Thermodynamics
Aysenur Ates, Sueleyman Celik, Vedat Yagci, Muhammed Caglar Malyemez, Murat Parlak, Abdolali K. Sadaghiani, Ali Kosar
Summary: Flow boiling of dielectric fluids in minichannels provides promising cooling alternatives for achieving high heat flux cooling. Experimental investigations on flow boiling performance in minichannels were conducted with six different surface characteristics and HFE-7000 as the working fluid. The results revealed different flow patterns, including single-phase flow, bubbly flow, intermittent flow, and annular flow. It was found that the presence of elliptical pin fins significantly enhanced the flow boiling performance, while the presence of distribution pin fins improved flow distribution and heat transfer. Tip clearance also exhibited a positive effect at low values (<5%).
APPLIED THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Kitti Nilpueng, Mehrdad Mesgarpour, Lazarus Godson Asirvatham, Ho Seon Ahn, Omid Mahian, Somchai Wongwises, Ahmet Selim Dalkilic
Summary: The study investigated the effects of different shapes, orientations, and distances on the air flow and heat transfer characteristics inside plate pin fin heat sinks. Results showed that under the same area, square pin fin heat sinks had higher heat transfer coefficient and pressure drop compared to circular pin fin heat sinks, while decreasing the distance led to an increase in heat transfer coefficient and pressure drop.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Mohanad A. Alfellag, Hamdi E. Ahmed, Mohammed Gh Jehad, Marwan Hameed
Summary: The numerical investigation compared the Metal Foam Pin-Fin Heat Sink (MFPFHS) to the traditional Solid Pin-Fin Heat Sink (SPFHS) and found that the MFPF exhibited superior heat dissipation and reduced frictional losses. The study also showed that increasing the pin diameter ratio and the number of pins in the MFPF resulted in significant heat transfer enhancement and performance evaluation criteria improvement.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Thermodynamics
Yin Xie, Yu Rao, Peng Zhang
Summary: The study investigates the turbulent flow and heat transfer over channel surfaces with V ribs and V-rib-dimple compound turbulators using Scale-Adaptive Simulations (SAS). The presence of dimples significantly enhances heat transfer and depends on the channel length. The introduction of dimples expands the range of increasing regional heat transfer and reduces shear stress on the sidewall.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Shengchen Li, Zixin Deng, Jian Liu, Defu Liu
Summary: In this paper, a multi-objective optimization approach based on computational fluid dynamics and non-dominated sequencing genetic algorithm was applied to optimize the performance of a plate-fin heat exchanger. The optimal parameter combination was determined using support vector machine regression and technique for order preference by similarity to an ideal solution method. The results showed that the plate-fin heat exchanger achieved its best heat transfer performance under specific parameter settings.
APPLIED SCIENCES-BASEL
(2022)
Article
Thermodynamics
Yong Eng, C. M. J. Tay, B. C. Khoo
Summary: In this study, the flow characteristics and enhanced heat transfer performance of circular dimples in a channel flow were analyzed numerically and compared with a flat channel. It was found that shifting the deepest point of the dimples downstream can significantly suppress the induced recirculating flow, enhancing the heat transfer performance. The flow structure above the dimpled wall is also influenced by the geometry changes, and the flow impingement on the dimpled wall increases drag.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Thermodynamics
Yacine Khetib, Khaled Sedraoui, Abdellataif Gari
Summary: This study numerically investigated a micro-pin-fin heat sink to improve its cooling capability and productivity. It found that the RS configuration had the maximum heat transfer while also yielding the maximum pressure drop.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Kefeng Yang, Yongfeng Sui, Xiangyu Wang, Zhenping Feng
Summary: This study investigates the flow and heat transfer characteristics in rectangular channels containing lantern-shaped pins with different sphere-to-pin diameter ratios. The numerical simulations show that the spheres behind the pins enhance the Nusselt number and pressure loss. The results also indicate that the lantern-shaped pin with higher sphere-to-pin diameter ratio has better thermal performance.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
