Search Results (22)

In this study, the effects of different heat sink designs on the cold side of the modules in a thermoelectric generator (TEG) system placed between the compressor and the intercooler of a turbocharged tractor on the system performance were numerically analyzed. In the current literature, heat sinks used in TEG modules generally consist of plate fins. In this study, by using perforated and slotted fins, the thermal boundary layer behaviors were changed and there was an attempt to increase the heat transfer from the cold surface compared to plate fins. Thus, the performance of the TEG system was also increased. When looking at the literature, it is seen that there are studies which aim to increase the performance of TEG modules by changing the dimensions of p and n type semiconductors. However, there is no study aiming to increase the performance of TEG modules by making changes on the plate fins of the heat sinks used in these modules and thus increasing the heat transfer amount. In this respect, this study offers important results for the literature. According to the numerical analysis results, the total TEG output power, output voltage, and thermal efficiency obtained for S0.5H15 were 6.2%, about 3%, and about 5% higher than those for PF, respectively. In addition, the pressure drop values obtained for different heat sinks, except for aluminum foam, were approximately close to each other. In cases with TEG systems where different heat sinks were used, the intercooler inlet air temperatures decreased by approximately 3.4–3.5% compared to the case without the TEG system. This indicates that the use of TEG will positively affect the improvement in engine efficiency. Full article

Thermoelectric generator (TEG) has emerged as a critical technology for automotive exhaust energy recovery, yet there is still a lack of reviews analyzing automotive TEG structure design and optimization methods simultaneously. Therefore, this review consolidates structure design and methods for improving thermoelectric conversion efficiency, focusing on three core components: thermoelectric module (TEM), heat exchanger (HEX), and heat sink (HSK). For TEM, research and development efforts have primarily centered on material innovation and structural optimization, with segmented, non-segmented, and multi-stage configurations emerging as the three primary structural types. HEX development spans external geometries, including plate, polygonal, and annular designs, and internal enhancements such as fin, heat pipe, metal foam, and baffle to augment heat transfer. HSK leverages active, passive, or hybrid cooling systems, with water-cooling designs prevalent in automotive TEG for cold-side thermal management. Optimization methods encompass theoretical analysis, numerical simulation, experimental testing, and hybrid methods, with strategies devised to balance computational efficiency and accuracy based on system complexity and resource availability. This review provides a systematic framework to guide the design and optimization of automotive TEG. Full article

Efficient cooling is necessary for the reliability of phased-array radars for a longer life. With the miniaturization and functionalization of microchips, heat flux generated by these chips also rises sharply. Existing liquid cooling techniques are inadequate to meet the ever-increasing cooling requirements. The present paper examines the potential to enhance the convective heat transfer of minichannel heat sinks (MCHSs). Two types of double serpentine minichannel heat sinks are investigated and compared. The first one is a traditional-design MCHS with plate fins, while the second one is a performance-enhanced MCHS design. Three-dimensional conjugate heat transfer models are developed, and the equations governing flow and energy are solved numerically with ANSYS Icepak. The results indicate that the novel MCHS design is found to significantly reduce both the average pressure drop across the minichannels and the total thermal resistance by up to 51% and 8.5%, respectively. Meanwhile, heat transfer enhancement can be obtained for all the rib oblique angles from 13° to 163°, while lowest average pressure drop can be obtained near 90°. The present study provides a new choice for researchers to design more effective MCHSs for the cooling of modern phased-array radar high-heat-flux chips. Full article

Effective thermal management of electronic modules is crucial to the reliable operation of variable frequency air conditioners. For this reason, two types of plate-finned heat sinks of electronic modules were selected. The experiments utilized ceramic heating plates to simulate chip heating, conducted in an enthalpy difference laboratory with controlled environments. Four installation cases were analyzed to evaluate the impact of heat sink orientation, airflow direction, and structural layout. The results showed that when multiple chips were arranged on the same heat dissipation substrate, the heat dissipation process of the chips would be coupled with each other, and the rational layout of the chips played an important role in heat dissipation. In the case of cooling air impacting the jet, the heat dissipation performance of the heat sink was significantly improved, and the heat transfer coefficient of the heat sink was as high as 316.5 W·m⁻²·°C⁻¹, representing a 6.9% improvement over conventional designs (case I: 296.1 W·m⁻²·°C⁻¹). The maximum temperature of the chips could be reduced by 11.1%, which is 10.1 °C lower. This study will provide a reference for the optimization design of the heat sink of the electric control module in inverter air conditioners. Full article

The onboard circuits of EV chargers comprise heat-producing electronic devices such as MOSFETs and diodes for switching and power conversion operations. A heatsink must dissipate this generated heat to extend the devices’ life and prevent component thermal stress or failure. This study primarily investigates the optimal heatsink geometry and pin configuration, which offers the most efficient temperature versus cost performance. MATLAB/Simulink (R2024a) was used to model a Level 1 charger using eight MOSFETs and four diodes. Various heatsink geometries were modeled using the ANSYS (2024 R1) Workbench and Fluent software to optimize the sink’s thermal performance. The analyses were performed under transient conditions using natural and forced cooling scenarios. The 2 mm wide plate fin heatsink with 44 fins yielded the best result. Further enhancement of the best-performing naturally cooled model improved the switches and diodes temperatures by 14% and 4%, respectively. The performance of the heatsink was further improved by applying a cooling fan to achieve an up to 25% diode and 40% MOSFET thermal dissipation efficiency. The results of this study show that the most efficient cooling performance and cost are realized when the optimum combination of fin spacing, proximity from the cooling fan, and fin geometry is selected. Full article

The primary objective of this study is to develop a simulation model for a liquid cooling plate (LCP) for insulated-gate bipolar transistor (IGBT) modules, with the aim of reducing the operating temperature of wind power converters (WPCs). The initial impetus for this study was the observation that the energy conversion efficiency of a WPC declines when the operating temperature of the IGBT module exceeds a critical threshold. Three LCPs, with and without heat sinks, were modelled under extreme conditions using the finite element simulation method. The effect of the number and height of the fins on the cooling efficacy was evaluated through the simulation and analysis of the LCP model with heat sinks. The results demonstrate that the optimal configuration, comprising five 10 mm fins and 13 10 mm struts, can achieve the following reductions: maximum temperature by 11.4 K, heat dissipation efficiency by 3.33%, pressure drop by 10.6 KPa, and pump power by 31.00%. Moreover, the findings suggest that the number of fins has a significant impact on temperature fluctuations, whereas the height of the fins exerts a markedly significant influence on pressure drop. Full article

One of the main trends in the development of the modern electronics industry is the miniaturization of electronic devices and components. Miniature electronic devices require compact cooling systems that can dissipate large amounts of heat in a small space. Researchers are exploring ways to improve the design of the heat sink of the cooling system in such a way that it increases the heat flow while at the same time reducing the size of the heat sink. Researchers have previously proposed different designs for heat sinks with altered fin shapes, perforations, and configurations. However, this approach to optimizing the design of the heat sink results in an increase in the labor intensity of its production. Our goal is to optimize the heat sink design to reduce its size, reduce metal consumption, and increase heat flow. This goal is achieved by changing the number of fins and the distance between them. In this case, there is no significant difference in the geometry of a conventional plate-fin heat sink, and a low labor intensity of production is ensured. A numerical investigation of heat flow and pressure drop in models of plate-fin heat sinks of various sizes and metal volumes was conducted using the ANSYS Fluent software package (v. 19.2) and computational fluid dynamics employing the control volume method. We used the SST k-ω turbulence model for the calculations. The research results showed that by changing the number of fins and the distance between them, it is possible to increase the heat flow from the heat sink to 24.44%, reduce its metal consumption to 6.95%, and reduce its size to 30%. The results of this study may be useful to manufacturers of cooling systems who seek to achieve a balance between the compactness of the heat sink and its ability to remove large amounts of heat. Full article

Applying sinusoidal vibration to heat sinks has proven to be a promising technique for improving heat transfer by disrupting the thermal boundary layer. However, applying sinusoidal vibration to the base of thin plate-fin heat sinks can cause a flapping motion within the fins, further enhancing heat transfer. Therefore, the current study numerically investigates and compares the effects of sinusoidal vibrations on the thermal performance of conventional and thin plate-fin heat sinks. The study concludes that increased vibrational amplitude and frequency (f ˃ 30 Hz) increases the vibration-assisted thermal performance. It was found that the thin plate-fin heat sink provides higher thermal performance compared to the conventional heat sink at every level of vibrational characteristics. The study found that the application of vibration enhances the Nusselt number up to a maximum of 20% and 15% in thin plate-fin and conventional heat sinks, respectively. Furthermore, the Reynolds number is reduced by 33.3% and 28% with thin plate-fin and conventional heat sinks compared with non-vibrating heat sinks, indicating a potential reduction of the size of the cooling system or fin size. Full article

Effective natural-convection-cooled heat sinks are vital to the future of electronics cooling due to their low energy demand in the absence of an external pumping agency in comparison to other cooling methods. The present numerical study was carried out with ANSYS Fluent and aimed at identifying a more-effective fin design for enhancing heat transfer in natural convection applications for a fixed base-plate size of 100 mm × 100 mm under an applied heat flux of 4000 W/m². The Rayleigh number used in the present study lied within the range of 2.6 × 10⁶ to 4.5 × 10⁶. Initially, a baseline case with rectangular fins was considered in the present study, and it was optimized with respect to fin spacing. This optimized baseline case was then validated against the semi-empirical correlation from the scientific literature. Upon good agreement, the validated model was used for comparative analysis of different heat sink configurations with rectangular, trapezoidal, curved, and angled fins by constraining the surface area of the heat transfer. The optimized fin spacing obtained for the baseline case was also used for the other heat sink configurations, and then, the fin designs were further optimized for better performance. However, for the angled fin case, the optimized configuration found in the scientific literature was adopted in the present study. The proposed novel curved fin design with a shroud showed a 4.1% decrease in the system’s thermal resistance with an increase in the heat transfer coefficient of 4.4% when compared to the optimized baseline fin case. The obtained results were further non-dimensionalized with the proposed scaling in terms of the baseline case for the two novel heat sink cases (trapezoidal, curved). Full article

In this study, a fluid–thermal–electrical multiphysics numerical model was developed for the thermal and electrical analyses of a heat sink-based thermoelectric generator (TEG) in a waste heat recovery system used for casting a bronze ingot mold. Moreover, the model was validated based on experimental data. Heat sinks were installed on the hot side of the TEG module to recover the waste heat from the flue gas generated in the casting process. The numerical results of the thermal and electrical characteristics of a plate fin (PF)-based TEG showed good agreement with the experimental findings. Numerical simulations of heat sinks with three different fin structures—PF, cylinder pin fin (CPF), and rectangular pin fin (RPF)—were conducted. The simulated system pressure drop, hot- and cold-side temperature difference in the TEG module, TEG power output, and TEG efficiency were compared for the differently designed fin structures. The results showed that for the same fin area, the CPF heat sink-based TEG system achieved a lower pressure drop, higher power output, and higher efficiency than the other two designs. This was particularly true when the velocity of the flue gas and the fin height exceed 5 m/s and 28.6 mm, respectively. Therefore, for low and high flue gas velocities, PF and CPF heat sinks are recommended as the best choices, respectively. Full article

The thermal management of electronic devices has become a major problem in recent years. Therefore, there is a growing need for research on many new materials and innovative fluids due to the developing technology and increasing cooling need in electronic systems. In this paper, heat transfer from a plate fin and pin fin type heat sinks that were placed in a water block that are used in electronic systems was investigated. A base fluid (pure water) and 0.1% mass concentration Al₂O₃-H₂O nanofluid were used as cooling fluids. The experiments were carried out for volumetric flow rates varying between 100 and 800 mL/min and heat flux values of 454.54 W/m² and 1818.18 W/m². The results demonstrated that the Al₂O₃-H₂O nanofluid on the empty surface provided a maximum improvement of 10.5% in heat transfer compared to the base fluid. In the use of plate finned heat sink, the maximum amount of improvement in heat transfer compared to the empty surface was obtained approximately 64.25% for the base fluid and 82.8% for the nanofluid. A similar comparison was made for the pin-fin heat sink, a maximum thermal improvement of 56.4% in the base fluid and 70.27% in the use of nanofluid was determined. Full article

The efficiency of a thermochemical energy storage system can be improved by optimizing the structure of the thermochemical energy storage reactor. We proposed two modified structures for indirect heat transfer thermochemical energy storage reactors for a Ca(OH)₂/CaO system to improve their heat transfer performance. Our results showed that improving convective heat transfer offered varying effects on heat transfer performance in different reaction processes. For a half-plate pin fin sinks (HPPFHS) reactor and a plate pin fin sinks (PPFHS) reactor, enhancing the convective heat transfer process could improve the heat transfer performance in the dehydration process for a porosity of 0.5, and the time needed to complete reaction was reduced by around 33% compared with plate fin sinks (PFHS) reactor. As for the hydration process, because heat conduction along the bed dominated heat transfer performance, this method had little effect. Furthermore, we found that enhancing heat conduction along the bed and convective heat transfer had different effects on reaction process at different reaction areas. The HPPFHS reactor had a lower pressure drop along the HTF channel and exorbitant velocity of heat transfer fluid (HTF) was unnecessary. Under the condition of the bed porosity of 0.8, due to the lower thermal conductivity of material, both modified reactor structures had little effect on dehydration. However, because the temperature difference between bed and HFT was bigger, the PPFHS reactor could reduce the time of completing the hydration reaction by 20%. Above all, when planning to modify the reactor structure to improve the heat transfer performance to enhance the reaction process, the heat conditions along the bed, convective heat transfer between HTF and the bed and material parameters should be considered totally. Full article

This study introduces an enhanced thermal management strategy for efficient heat dissipation from GaN power amplifiers with high power densities. The advantages of applying an advanced liquid-looped silicon-based micro-pin fin heat sink (MPFHS) as the mounting plate for GaN devices are illustrated using both experimental and 3D finite element model thermal simulation methods, then compared against traditional mounting materials. An IR thermography system was equipped to obtain the temperature distribution of GaN mounted on three different plates. The influence of mass flow rate on a MPFHS was also investigated in the experiments. Simulation results showed that GaN device performance could be improved by increasing the thermal conductivity of mounting plates’ materials. The dissipated power density of the GaN power amplifier increased 17.5 times when the mounting plate was changed from LTCC (Low Temperature Co-fired Ceramics) (k = 2 Wm⁻¹ K⁻¹) to HTCC (High-Temperature Co-fired Ceramics) (k = 180 Wm⁻¹ K⁻¹). Experiment results indicate that the GaN device performance was significantly improved by applying liquid-looped MPFHS, with the maximum dissipated power density reaching 7250 W/cm². A thermal resistance model for the whole system, replacing traditional plates (PCB (Printed Circuit Board), silicon wafer and LTCC/HTCC) with an MPFHS plate, could significantly reduce θ_js (thermal resistance of junction to sink) to its theoretical limitation value. Full article

Because the delta winglet in common-flow-down configuration has been recognized as an excellent type of vortex generators (VGs), this study aims to experimentally and numerically investigate the thermo-hydraulic performance of four different forms of winglet VGs featuring sweptback delta winglets in the channel flow in the range 200 < Re < 1000. Both Nusselt number and friction factor of plate-fin heat sinks having different forms of winglets, including delta winglet pair (DWP), rectangular winglet pair (RWP), swept delta winglet pair (SDWP), and swept trapezoid winglet pair (STWP), were measured in a standard wind tunnel without bypass in this study. Four rows of winglets with in-line arrangement were punched on each 10-mm-long, 0.2-mm-thick copper plate, and a total of 16 pieces of copper plates with spacing of 2 mm were fastened together to achieve the heat sink. The projected area, longitudinal and winglet tip spacing, height and angle of attack of those winglets were fixed. Besides that, three-dimensional numerical simulation was also performed in order to investigate the temperature and fluid flow over the plate-fin. The results showed that the longitudinal, common-flow-down vortices generated by the VGs augmented the heat transfer and pressure drop of the heat sink. At airflow velocity of 5 m/s, the heat transfer coefficient and pressure drop of plain plate-fin heat sink were 50.8 W/m²·K and 18 Pa, respectively, while the heat transfer coefficient and the pressure drop of heat sink having SDWP were 70.4 W/m²·K and 36 Pa, respectively. It was found that SDWP produced the highest thermal enhancement factor (TEF) of 1.28 at Re = 1000, followed by both RWP and STWP of similar TEF in the range 200 < Re < 1000. The TEF of DWP was the lowest and it was rapidly increased with the increase of airflow velocity. Full article

The performance of impingement air cooled plate fin heat sinks differs significantly from that of parallel flow plate fin heat sinks. The impinging flow situations at the entrance and the right-angled bends of the plate fin heat sink are quite involved. Flow characteristics of a plate fin heat sink with elliptic bottom profiles cooled by a rectangular impinging jet with different inlet widths are studied by numerical simulations. The results of pressure drop of numerical simulations and experimental results match quite well. The numerical results show that at the same flow rate, the pressure drop decreases with the increase of the impingement inlet width, and the pressure drop increases significantly with the increase of the fin height. The larger the impingement inlet width of air-cooled plate fin heat sink, the milder the pressure drop changes with velocity. Pressure drop for an impinging plate fin heat sink without elliptic bottom profiles is larger than that with elliptic bottom profiles at the same inlet width and velocity. Based on the fundamental developing laminar continuum flow theory, an improved model which is very concise and nice for quick real world approximations is proposed. Furthermore, this paper verifies the effectiveness of this simple impinging pressure drop model. Full article