Thermal Radiative Copper Oxide Layer for Enhancing Heat Dissipation of Metal Surface

The heat dissipation of a metal heat sink for passive cooling can be enhanced by surface modifications to increase its thermal emissivity, which is reflected by a darker surface appearance. In this study, copper electrodeposition followed by heat treatment was applied to a copper substrate. The heat treatment formed a nanoporous oxide layer containing CuO and Cu2O, which has a dark blackish color and therefore increased the thermal emissivity of the surface. The heat dissipation performance was evaluated using the sample as a heat sink for an LED module. The surface-treated copper heat sink with a high thermal emissivity oxide layer enhanced the heat dissipation of the LED module and allowed it to be operated at a lower temperature. With an increase in the heat treatment, the thermal emissivity increases to 0.865, but the thermal diffusivity is lower than the copper substrate by ~12%. These results indicate that the oxide layer is a thermal barrier for heat transfer, thus optimization between the oxide thickness and thermal emissivity is required by evaluating heat dissipation performance in operating conditions. In this study, an oxide layer with an emissivity of 0.857 and ~5% lower thermal diffusivity than the copper substrate showed the lowest LED operating temperature.

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Design and characterization of a copper microchannel heat sink for SiP cooling

Modern Physics Letters B ◽

10.1142/s0217984921400157 ◽

2021 ◽

pp. 2140015

Author(s):

Min Miao ◽

Hao Zhang ◽

Hejie Yu ◽

Lili Cao

Keyword(s):

Heat Flux ◽

Heat Sink ◽

Heat Dissipation ◽

Electrical Discharge Machining ◽

Copper Substrate ◽

Integrated System ◽

Peak Temperature ◽

Microchannel Heat Sink ◽

Set Up ◽

Electronic Hardware

With the increasing flourishing of miniaturized, multifunctional, and heterogeneously integrated system in package (SiP), heating problem is becoming more and more serious. In this paper, to meet the heat dissipation needs of the chips thus assembled and to achieve effective thermal management, linear, serpent and spiral shaped microchannel heat sinks were designed and fabricated into copper substrate by electrical discharge machining (EDM) and precision machining technology, acting both as the cooler and mounting base for passive and active SiP interposers. A test platform was set up to characterize the heat dissipation performance of the copper-based microchannel heat sink. The experimental and simulation results show that heat dissipation rate increases with the increasing heat flux density in the range 5–30 W/cm2 for the three microchannel designs, and the peak temperature can all be kept below 340 K (67[Formula: see text]C) even for the highest heat flux. The three designs are compared from the perspective of peak temperature, temperature distribution uniformity and pressure drop. In all, the solution proposed hereby provides a new and optimal option for in-situ cooling for densely integrated electronic hardware.

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Effect of Synthetic Jets Over Natural Convection Heat Sinks

Volume 10: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B, and C ◽

10.1115/imece2008-68784 ◽

2008 ◽

Cited By ~ 2

Author(s):

Mehmet Arik ◽

Yogen Utturkar ◽

Murat Ozmusul

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Heat Sink ◽

Heat Dissipation ◽

Synthetic Jet ◽

Synthetic Jets ◽

Operating Conditions ◽

Heat Sinks ◽

Junction Temperature ◽

Allowable Limit

In moderate power electronics applications, the most preferred way of thermal management is natural convection to air with or without heat sinks. Though the use of heat sinks is fairly adequate for modest heat dissipation needs, it suffers from some serious performance limitations. Firstly, a large volume of the heat sink is required to keep the junction temperature at an allowable limit. This need arises because of the low convective film coefficients due to close spacing. In the present computational and experimental study, we propose a synthetic jet embedded heat sink to enhance the performance levels beyond two times within the same volume of a regular passive heat sink. Synthetic jets are meso-scale devices producing high velocity periodic jet streams at high velocities. As a result, by carefully positioning of these jets in the thermal real estate, the heat transfer over the surfaces can be dramatically augmented. This increase in the heat transfer rate is able to compensate for the loss of fin area happening due to the embedding of the jet within the heat sink volume, thus causing an overall increase in the heat dissipation. Heat transfer enhancements of 2.2 times over baseline natural convection cooled heat sinks are measured. Thermal resistances are compared for a range of jet operating conditions and found to be less than 0.9 K/W. Local temperatures obtained from experimental and computational agreed within ± 5%.

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Effect of Surface Microstructure on the Heat Dissipation Performance of Heat Sinks Used in Electronic Devices

Micromachines ◽

10.3390/mi12030265 ◽

2021 ◽

Vol 12 (3) ◽

pp. 265

Author(s):

Yuxin You ◽

Beibei Zhang ◽

Sulian Tao ◽

Zihui Liang ◽

Biao Tang ◽

...

Keyword(s):

Surface Roughness ◽

Thermal Radiation ◽

Heat Sink ◽

Heat Dissipation ◽

Electronic Devices ◽

High Heat ◽

Heat Sinks ◽

High Heat Flux ◽

Thermal Emissivity ◽

Effect Of Surface

Heat sinks are widely used in electronic devices with high heat flux. The design and build of microstructures on heat sinks has shown effectiveness in improving heat dissipation efficiency. In this paper, four kinds of treatment methods were used to make different microstructures on heat sink surfaces, and thermal radiation coating also applied onto the heat sink surfaces to improve thermal radiation. The surface roughness, thermal emissivity and heat dissipation performance with and without thermal radiation coating of the heat sinks were studied. The result shows that with an increase of surface roughness, the thermal emissivity can increase up to 2.5 times. With thermal radiation coating on a surface with microstructures, the heat dissipation was further improved because the heat conduction at the coating and heat sink interface was enhanced. Therefore, surface treatment can improve the heat dissipation performance of the heat sink significantly by enhancing the thermal convection, radiation and conduction.

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Investigation of the Thermal Performance of Salt Hydrate Phase Change of Nanoparticle Slurry Flow in a Microchannel

Journal of Chemistry ◽

10.1155/2019/5271923 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Safi A. Memon ◽

M. B. Sajid ◽

M. S. Malik ◽

Awad B. S. Alquaity ◽

M. Mohib ur. Rehman ◽

...

Keyword(s):

Phase Change ◽

Thermal Performance ◽

Lauric Acid ◽

Heat Sink ◽

Heat Dissipation ◽

Computational Study ◽

Operating Conditions ◽

Slurry Flow ◽

Design Guideline ◽

Salt Hydrate

Computational study was conducted to investigate the thermal performance of water-based salt hydrate S44 nanoparticles as the phase change material (PCM) in a microchannel heat sink. Constant heat dissipation was applied on the top wall of the heat sink. Forced internal convection of the PCM slurry flow was performed through a homogeneous approach. Three thermal performance parameters, including effectiveness ratio, performance index, and Merit number, were used to quantify the cooling performance of S44 for various concentrations of the PCM nanoparticles. The thermal performance of the salt hydrate S44 slurry was also compared with a similar study conducted for lauric acid nanoparticle slurry found in the literature. Specific operating conditions were identified. The salt hydrate S44 would provide better thermal performance than lauric acid, and vice versa. Finally, Nusselt number correlations have been developed for the microchannel PCM heat sink for Reynolds numbers in the range 12.23 to 47.14 and Prandtl numbers in the range 3.74 to 5.30. A design guideline for manufacturing PCM particles and microchannel heat sinks is provided. With this guideline, the heat absorption ability of the heat sink is maximized, and the pumping power and the losses related to the addition of the particles are minimized.

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Thermal and Structural Response of Pin Fins for Different Interface Conditions

Volume 4: Electronics and Photonics ◽

10.1115/imece2010-39972 ◽

2010 ◽

Author(s):

Abul Fazal M. Arif ◽

Sulaman Pashah ◽

Syed M. Zubair ◽

M. Inam

Keyword(s):

Thermal Performance ◽

Heat Sink ◽

Heat Dissipation ◽

Structural Response ◽

Operating Conditions ◽

Stress Fields ◽

Power Device ◽

Interface Conditions ◽

Thermal Interface ◽

Pin Fin

Thermal management of electronic products relies on the effective dissipation of heat. Heat sink elements (e.g. a pin fin) are used for any effective heat dissipation network. Despite much optimized design of the heat sink element, the heat transfer may not be effective because the interface between power device and heat sink element is critical in the heat dissipation network. Thermal Interface Materials TIM (e.g. adhesive, solder, pads, or pastes) are employed at interface between power device and heat sink element to minimize the interface thermal resistance. However, several challenges need to be addressed before they can be successfully utilized because depending on the thermal interface conditions, the thermal stress level can attain undesirable values. This issue can be addressed by the optimization of the system design with the help of simulation methods. Generally the effects of interface conditions are studied on the thermal performance of the heat sink system whereas in this paper, a coupled-field (thermal-structural) analysis using FEM is performed to study the thermal as well as structural behavior of the heat sink system. Temperature variation and stress fields in the region of interface between pin fin and base plate are analyzed. Effects of various parameters (such as contact pressure, surface roughness, TIM thickness, and operating conditions) on the resulting thermal and structural response at the interface are presented. It has been found that different interface conditions may have comparable thermal performance with significant different stress fields at the interface. Therefore stress state must be known to ensure the structural integrity of the heat sink system for a given operating condition.

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Viability of turbine blade material with a long service life

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-97-1-28-35 ◽

2019 ◽

pp. 28-35

Author(s):

O. B. Berdnik ◽

I. N. Tsareva ◽

M. K. Chegurov

Keyword(s):

Heat Treatment ◽

Service Life ◽

Yield Strength ◽

Mechanical Characteristics ◽

Operating Time ◽

Structural Features ◽

Operating Conditions ◽

Standard Methods ◽

Experimental Values ◽

Plasticity Coefficient

This article deals with structural features and characteristic changes that affect the mechanical characteristics after different service life in real conditions using the example of the blades of the 4th stage of turbine GTE-45-3 with an operating time of 13,000 to 100,000 hours. To study the change in the state of the material under different operating conditions, determine the degree of influence of heat treatment on the regeneration of the microstructure, and restore the mechanical characteristics of the alloy after different periods of operation, non-standard methods were used: relaxation tests on miniature samples to determine the physical yield strength and microplasticity limit and quantitative evaluation of the plasticity coefficient of the material from experimental values of hardness, which allow us to identify the changes occurring in the microvolumes of the material and predict the performance of the product as a whole.

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Thermal Behaviors of Passively-Cooled Hybrid Fin Heat Sinks for Lightweight and High Performance Thermal Management

Volume 1: Thermal Management ◽

10.1115/ipack2015-48630 ◽

2015 ◽

Cited By ~ 1

Author(s):

Nico Setiawan Effendi ◽

Kyoung Joon Kim

Keyword(s):

Thermal Resistance ◽

Heat Sink ◽

High Performance ◽

Heat Dissipation ◽

Computational Study ◽

Heat Sinks ◽

Channel Diameter ◽

Internal Channel ◽

Study Results ◽

Parametric Effects

A computational study is conducted to explore thermal performances of natural convection hybrid fin heat sinks (HF HSs). The proposed HF HSs are a hollow hybrid fin heat sink (HHF HS) and a solid hybrid fin heat sink (SHF HS). Parametric effects such as a fin spacing, an internal channel diameter, a heat dissipation on the performance of HF HSs are investigated by CFD analysis. Study results show that the thermal resistance of the HS increases while the mass-multiplied thermal resistance of the HS decreases associated with the increase of the channel diameter. The results also shows the thermal resistance of the SHF HS is 13% smaller, and the mass-multiplied thermal resistance of the HHF HS is 32% smaller compared with the pin fin heat sink (PF HS). These interesting results are mainly due to integrated effects of the mass-reduction, the surface area enhancement, and the heat pumping via the internal channel. Such better performances of HF HSs show the feasibility of alternatives to the conventional PF HS especially for passive cooling of LED lighting modules.

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Effect of Heat Sink Structure Improvement on Heat Dissipation Performance in High Heat Flux

Volume 1: Micro/Nanofluidics and Lab-on-a-Chip; Nanofluids; Micro/Nanoscale Interfacial Transport Phenomena; Micro/Nanoscale Boiling and Condensation Heat Transfer; Micro/Nanoscale Thermal Radiation; Micro/Nanoscale Energy Devices and Systems ◽

10.1115/mnhmt2016-6726 ◽

2016 ◽

Author(s):

Zhuo Cui

Keyword(s):

Heat Resistance ◽

Water Flow ◽

Heat Sink ◽

Heat Dissipation ◽

Convection Heat Transfer ◽

Cooling Water ◽

High Heat Flux ◽

Pin Fin ◽

Pin Fins ◽

Pin Fin Arrays

This paper presents the effects of heat dissipation performance of pin fins with different heat sink structures. The heat dissipation performance of two types of pin fin arrays heat sink are compared through measuring their heat resistance and the average Nusselt number in different cooling water flow. The temperature of cpu chip is monitored to determine the temperature is in the normal range of working temperature. The cooling water flow is in the range of 0.02L/s to 0.15L/s. It’s found that the increase of pin fins in the corner region effectively reduce the temperature of heat sink and cpu chip. The new type of pin fin arrays increase convection heat transfer coefficient and reduce heat resistance of heat sink.

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