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Thermal management materials used for heat sink in laptop computers is reviewed in this paper. In laptop computers, heat sink plays a vital role of dissipating heat from the system. Heat sink is a vital component in a laptop computer because it dissipates the heat generated by the system. The overall efficiency, cost, and size of the system could b...
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... Phases [82]. It's worth mentioning that the estimated thermal conductivity (K ph ) at 300 K is higher than that of many popular MAX phase compounds, bronze, aluminumbronze, and red brass [82][83][84]. ...
... Phases [82]. It's worth mentioning that the estimated thermal conductivity (K ph ) at 300 K is higher than that of many popular MAX phase compounds, bronze, aluminumbronze, and red brass [82][83][84]. ...
... Metal materials, such as aluminum, copper, zinc, are the most used as heat sinks [3]. Passive cooling technology relies on maximizing heat transfer by conduction, radiation, and convection using heat sinks, heat spreaders, heat pipes, or thermal interface materials to maintain optimal operating temperatures. ...
... It is clear that the material, together with the structural and architectural design of heat sink, is crucial to increase efficiency levels of active cooling systems. Great efforts have been made to improve the performance of current heat sinks, such as the modification of the architectural designs [8][9][10][11], development of composite materials with enhanced thermal properties (metal-SiC, metal-graphene/diamond) [3,[12][13][14], and study and control of the structure to enhance their thermal conductivity (e.g., porosity) [14]. Therefore, to improve the efficiency of active cooling systems, there must be an optimization of solid materials acting as heat sinks/spreaders/pipes and active components, such as fluids and those related to mechanical forces (fan, pump, etc.). ...
It is well known that by dispersing nanoparticles in a fluid, the thermal conductivity of the resulting nanofluid tends to increase with the concentration of nanoparticles. However, it is not clear what the mechanism behind this phenomenon is. Raman spectroscopy is a characterization technique connecting the molecular and macroscopic world, and therefore, it can unravel the puzzling effect exerted by the nanomaterial on the fluid. In this work, we report on a comparative study on the thermal conductivity, vibrational spectra and viscosity of graphene nanofluids based on three different amides: N, N-dimethylacetamide (DMAc); N, N-dimethylformamide (DMF); and N-methyl-2-pyrrolidinone (NMP). A set of concentrations of highly stable surfactant-free graphene nanofluids developed in-house was prepared and characterized. A correlation between the modification of the vibrational spectra of the fluids and an increase in their thermal conductivity in the presence of graphene was confirmed. Furthermore, an explanation of the non-modification of the thermal conductivity in graphene-NMP nanofluids is given based on its structure and a peculiar arrangement of the fluid.
... Good choice of heat sink's material will enhance the device performance, leading to optimal thermal management [12]. Although, literature is rich with studies focusing on improving the performance of heat sinks devices either by numerical techniques [1,13], or by optimization the geometry [14], few studies discussed the materials selection for heat sinks [12,15]. The goal of this study is to use AHP for selecting the best material for heatsink devices, especially no work has been done on the use of decision making techniques for this application. ...
... Based on the parameters and design aspects considered, and the analysis using governing equations for heat transfers, the best performance can be achieved by maximizing (λ, E, ρe) and minimizing α. Therefore, two types of graphs were developed for the purpose of comparing different classes of materials; the first graphs plot (λ vs. ρe), and the second graph plots (α vs. E) [15]. As none of the existing papers utilized the multicriteria decision problem for selecting the heatsinks material that give the best performance, this study aims to use AHP method for this purpose. ...
In this study, the analytical hierarchical process (AHP) is used to find the best material for making heatsink devices used in microelectronic and labtops. The model is built using five criteria, including: thermal conductivity, thermal expansion coefficient, electrical resistance, modulus of elasticity, cost, and density. Aluminum, copper, Al 5050-O , beryllium S-65 C, and aluminum nitiride were used as alternatives to select among them. The results show that aluminum is the best material for this application owing to its low density, low cost, and acceptable thermal conductivity. Both inconsistency and sensitivity analysis were done and showed that model is robust.
Hexagonal boron nitride (h-BN) is one of the promising two-dimensional (2D) materials to enhance the thermal, optical, electrical, and mechanical properties of polymer nanocomposites. Among many nanofillers used to develop highly thermal conductive polymeric nanocomposites, h-BN has excellent thermal conductivity, high thermal and chemical stability, and electrical insulating properties with a large band gap (~6 eV) that carbon nanotube and graphene cannot provide. Usual methods that involve solution-based reactions could not be used because of the poor wetting properties of h-BN nanofillers like BN nanotubes (BNNTs) and BN nanosheets (BNNSs) caused by low chemical reactivity of these fillers. Research on surface chemistry and modification, size, shape, and volume fraction of BNNSs is essential for the general understanding of the thermal conductivity of polymeric nanocomposites, which is critical for identifying the material needs in various industrial applications with a wide range of thermal conductivity requirements. Polymer scientists have a distinct understanding of the critical need for the amount of research work on this emerging topic and the need for close collaborations between industry and academia. The purpose of this chapter is to cover and review conducted research in advanced thermally conductive materials, especially on the use of thermal management systems and their validation of advanced materials by nanoscale control of their properties.
We report the enhanced cooling performance of the phase change material (PCM)-integrated fin-type heat sink compared to conventional fin-type heat sink in high power electronics with two localized hot spots. The PCM-integrated fin-type heat sink is fabricated by embedding the phase change composite to the base plate of the heat sink. As an effort to effectively utilize thermal capacitive effects of PCM, the phase change composites with paraffin infiltrated to copper foams are deployed within circular hole arrays in the base plate, which is subsequently covered by a graphite sheet, to achieve excellent heat spreading characteristics. Considering the cooling environments of commercial high power electronics (insulated-gate bipolar transistor (IGBT)), thermal performance of the PCM-integrated and the conventional fin-type heat sinks is experimentally and numerically investigated upon the heating powers of 400∼800 W. While the PCM-integrated fin-type heat sinks have similar heat sink thermal resistance with the conventional fin-type heat sinks, the PCM-integrated fin-type heat sinks exhibit an effective time delay up to ∼27.3% of the hot-spot temperature rise until 80 ℃ of the heat sinks in reduced cooling conditions, showing the potential as an effective thermal managing platform of the PCM-integrated heat sinks in convection-limited cooling environments.
Thinned CMOS chips transfer-bonded onto a compliant host substrate remain to date the technology of choice for applications requiring both mechanical flexibility and high frequency operation. However, the use of poorly thermally conductive host substrates raises the problem of thermal management of flexible electronics, a topic poorly addressed in literature. In this letter, we report the analysis of flexible SOI-CMOS chips ultimately-thinned-and-transfer-bonded (UTTB) onto polyimide and copper substrates. While the temperature remains limited to 68∘C on the native silicon substrate or after transfer onto a copper host substrate, infrared thermography reveals temperature peaks of up to 118∘C on polyimide. The impact of self-heating in flexible SOI-CMOS is correlated with electrical performance for the three types of substrates. Beyond the property of mechanical flexibility it provides, a copper substrate is shown to slightly strengthen electrostatic integrity while maintaining a thermal landscape close to that of silicon.
Light Emitting Diode (LED) has several advantages and applications due to energy efficiency, versatility, performance and long life. LED converts only 20–30% power input into light, leaving 70–80% energy into heat that must be conducted from the LED die to the underlying circuit board, heat sinks, and housings. Improper thermal management will lead to increase in junction temperature above the safe limit, thus leading to premature failure of LED. The present investigation aims to study the variation of case and junction temperature for three types of heat sink viz., diagonal, cylindrical and spiral using 16W LED. Light output in terms of lux is measured. Experiments were conducted by varying current from 100mA to 300mA. It was observed that spiral heat sink has the least junction temperature and thermal resistance among the three heat sinks at all current rating.
This research presents an approach for predicting and optimizing the thermal resistance and mass of microelectronics heat sinks parameters. The Minitab software used the Taguchi design of experiments method to generate L27 Orthogonal array combinations for the heat sink geometry. The combinations consist of 6 factors (fin height, base thickness, fin thickness, length, number of fins, and width of heat sink) and 3 levels (low, medium, high). Ansys finite element software was used in the thermal analysis of the heat sink to determine the thermal resistance while the mass was calculated. The thermal resistance and mass responses were used to develop a multiple linear regression analysis model for predicting both thermal resistance and mass of heat sink. The developed regression model showed over 90% accuracy in predicting the thermal resistance and mass of heat sinks. In addition, the optimized heat sink geometry showed a 50.75% reduction in mass and 5.26% reduction in thermal resistance. This model could be used as an alternative to simulation software and could save cost and time in selecting an optimal heat sink for microelectronic applications.
