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To enhance the hydrothermal performance of micro pin fin heat sinks (MPFHSs), this paper proposes five MPFHSs with different streamwise pin fin height variation modes and experimentally and numerically compares their hydrothermal performance, including pressure drop, maximum and average temperatures, and comprehensive performance evaluation criteria. The results indicate that, taking the uniform PFs height (UH) design as a reference, the designs with linearly increasing streamwise PFs height (LIH) and increasing streamwise PFs height with decelerating growth rate (DIH) demonstrate lower heat sink temperatures. Conversely, the designs with linearly decreasing streamwise PFs height (LDH) and decreasing streamwise PFs height with accelerating reduction rate (ADH) result in higher heat sink temperature. In addition, the comprehensive performance of LDH and ADH outperforms that of UH at low inlet flow rates, while the DIH surpasses that of UH at higher flow rates. As the inlet flow rate increases from 0.02 L/min to 0.5 L/min, our numerical study shows that the comprehensive performance of LDH and ADH decreases by 14.9% and 6.2%, respectively, whereas that of LIH and DIH increases by 17.4% and 10.2%, respectively. This finding provides insights to improve the hydrothermal performance of MPFHS.

A concave-parabolic pin fin (spine) is considered within the present research. The thermal property of the spine is exhibited to be affected by a uniform oncoming airflow in an aim at improving its cooling performance. The mathematical model corresponding to one-dimensional physical layout is formulated first from the usual heat balance method. Exact and numerical solutions of the fin temperature distribution are then extracted from the model, relying upon two physical parameters: namely, the Peclet number Pe, controlling the magnitude of the airflow and the fin shape parameter α , adjusting the spine shape. It is shown that these parameters have high impacts on the performance of the parabolic pin fin towards cooling the medium it is attached to. Finally, optimum concave parabolic pin fins corresponding to a given volumetric region are identified by means of maximizing the base heat transfer rate. Interestingly, the optimum dimensions of the spine are found to be much influenced by the variation in Peclet number.

This research paper deals with the experimental thermodynamic analysis of a forced convection solar air heater using pin-fin absorber plate and compared with the standard flat absorber plate. The experiments were carried out during the months of February 2018 and March 2018 at Coimbatore city in India. The performance parameters such as, outlet air temperature, energy efficiency, thermohydraulic efficiency, and exergy efficiency are used for performance comparisons. The results showed that the pin-fin absorber plate has about 17 °C higher outlet air temperature when compared to the flat absorber plate. The energy efficiency of a forced convection solar air heater using pin-fin absorber plate was found to be 3% to 12% higher when compared to flat absorber plate with 2% to 11% higher exergy efficiency. The results confirmed that forced convection solar air heaters using pin-fin absorber plate is having significant performance improvement in thermodynamic performance with minimum pressure drop across the air heater duct.

An experimental investigation of a novel V-groove absorber plate with pin-fins on double-pass solar air collector was made to study the enhancement of thermal performance. The objective of this work is to develop a solar air collector for drying agricultural products with enhanced heat transfer rate by employing pin-fins on V-groove absorber plate under varied configurations. The parameters that influence the instantaneous thermal efficiency of the collector are discussed, and obtained results are compared with a conventional V-groove absorber plate for same mass flow rate values. Energy and exergy analyses were also carried out. The results show that the efficiency of the collector depends strongly on the flow rate. Also, it is noted that for a flow rate of 0.035 kg s−1, the novel V-groove absorber plate with pin-fins installed on both sides exhibits extended heat transfer area, thereby a rise in average thermal efficiency by 17.4%.

A novel microchannel heat sink with oval-shaped micro pin fins (MOPF) is proposed and the characteristics of fluid flow and heat transfer are studied numerically for Reynolds number (Re) ranging from 157 to 668. In order to study the influence of geometry on flow and heat transfer characteristics, three non-dimensional variables are defined, such as the fin axial length ratio (α), width ratio (β), and height ratio (γ). The thermal enhancement factor (η) is adopted as an evaluation criterion to evaluate the best comprehensive thermal-hydraulic performance of MOPF. Results indicate that the oval-shaped pin fins in the microchannel can effectively prevent the rise of heat surface temperature along the flow direction, which improves the temperature distribution uniformity. In addition, results show that for the studied Reynolds number range and microchannel geometries in this paper, the thermal enhancement factor η increases firstly and then decreases with the increase of α and β. In addition, except for Re = 157, η decreases first and then increases with the increase of the fin height ratio γ. The thermal enhancement factor for MOPF with α = 4, β = 0.3, and γ = 0.5 achieves 1.56 at Re = 668. The results can provide a theoretical basis for the design of a microchannel heat exchanger.

In this document, the numerical analysis of the non-uniformity of the height of fins of a pin fin heat sink on the firs law and second law performances of the heat sink is conducted. Five different designs for changing the height of pin fins in the longitudinal and transverse directions are considered and their hydrothermal performance and entropy generation characteristics at different Reynolds numbers are investigated. After examining the changes in convection coefficient, maximum CPU temperature, uniformity of temperature distribution, thermal resistance and overall hydrothermal performance index, it was found that the best first law performance belongs to the case in which the height of the pin fins elevates in the longitudinal direction and linearly by moving away from the inlet of the device. For this case, the maximum overall hydrothermal performance index was equal to 1.099, which occurred at Reynolds number of 500. Investigating the performance of the heat sinks from the entropy generation viewpoint also revealed that the lowest total entropy generation rate belongs to the device in which the height of the fins declines in the longitudinal direction and linearly by moving away from the inlet.

The escalating demand for heat dissipation has prompted considerable interest in the manifold micro-pin–fin heat sink (MMPFHS) as a promising solution for high heat flux cooling applications. The two-dimensional topology of this multi-layered heat sink plays a pivotal role in organizing the three-dimensional spatial flow, consequently influencing both hydraulic and thermal performance. This study proposes and comparatively analyzes the only three rhombus-based tiling topologies applicable to MMPFHS, specifically the rhombus topology (RT), triangle hexies topology (THT), and firecracker topology (FT), all of which adhere to the principles of gapless, non-overlapping, and spatially expandable tiling topology. The relations of topological geometry and the hydraulic and thermal performances are explored and compared. And figure of merit (FOM) is also introduced to assess their overall performance. The results indicate that the overall performance of THT is predominant. When D PF  = 100 μm, a  = 200 μm, D in  = 50, Re = 64.87, the temperature non-uniformity on the heating surface of THT is only 0.022 K, the thermal resistance is 9.4 × 10 –6  km 2  W −1 , and the FOM of THT is about 1.14 times of that of RT. RT and FT have a similar performance, and the maximum deviation of FOM for both of them within the conditions studied in this paper is only 0.04. The paper provides a reference for selecting topologies in MMPFHS design.

Electronic components used in high power dissipating equipment’s requires superior thermal management and system design should be good enough to serve its promised lifetime without any performance issues/early failures. Prime task for product designers is to keep the electronic devices temperature below threshold limit by dispelling generated heat. Most common and preferred electronics thermal management technique is air-cooled heatsinks with fans because of its heat dissipation range and most reliable simple technique. This review paper specifically aims to understand the recent advancements of air-cooled pin–fin heatsinks for heat transfer applications. This article focuses on available literature only on heatsinks of pin–fin type to explore the results of different types of geometry, orientation, spacing out, perforations on heat transfer performance. In addition to above analytical, numerical, experimental results and heat transfer correlations of different studies are compared and summarized. The outcome of this review article is to provide better understanding on the cooling performance of the pin–fin type heatsink technology and its effective usage towards better thermal management applications.

To enhance the thermo-hydraulic performance of cooling channels, this investigation examines the influence of distinct cross-sectional shapes (i.e., triangular, rectangular, and hexagonal) of twisted pin fins and their arrangements in straight and cross rows. An ambient air cooling test platform was established to numerically and experimentally investigate the flow and heat transfer characteristics of 360° twisted pin fins at Re =15 200–22 800. The findings reveal that straight rows exhibit higher Nu values than cross rows for triangular and rectangular twisted pin fins, and Nu increases with Re . In contrast, for hexagonal twisted pin fins, only straight rows at Re =19 000 exhibit superior overall thermal performance compared to cross rows. Notably, the heat transfer performance of the cooling channel with hexagonal twisted fins surpasses both triangular and rectangular configurations, especially at high Reynolds numbers ( Re =22 800). Although the heat transfer coefficient of the cooling channel with hexagonal twisted fins is significantly enhanced by 132.71% compared to the flat channel, it also exhibits the highest thermal resistance and relative friction among the three types of twisted fins, the maximum of which are 2.14 and 16.55. Furthermore, the hydrothermal performance factor (HTPF) of the cooling channels with different types of twisted pin fins depends on the Reynolds number and arrangement modes. At Re =15 200, the highest HTPF achieved for the cross-row hexagonal twisted pin fins is 0.99.

Pin-fins configurations have been investigated recently for different engineering applications and, in particular, for a cooling turbine. In the present study, we investigated the performance of three different pin-fins configurations: pin-fins forming a wavy mini-channel, pin-fins forming a straight mini-channel, and a mini-channel without pin-fins considering water as the working fluid. The full Navier–Stokes equations and the energy equation are solved numerically using the finite element technique. Different flow rates are studied, represented by the Reynolds number in the laminar flow regime. The thermo-hydraulic performance of the three configurations is determined by examining the Nusselt number, the pressure drop, and the performance evaluation criterion. Results revealed that pin-fins forming a wavy mini-channel exhibited the highest Nusselt number, the lowest pressure drop, and the highest performance evaluation criterion. This finding is valid for any Reynolds number under investigation.