Enhancing Heat Dissipation of Quantum Dots in High-Power White LEDs by Thermally Conductive Composites Annular Fins

This paper studies the development of new multifunctional liquid crystal polymeric composites filled with graphene nano platelets (GNPs) for electronic packaging applications. A series of parametric studies were conducted to study the effect of GNP content on the thermal conductivity of LCP-based nanocomposites. Graphene, ranging from 10 wt. % to 50 wt. %, were melt-compounded with LCP using a twin-screw compounder. The extrudates were ground and compression molded into small disc-shaped specimens. The thermal conductivity of LCP matrix was observed to have increased by more than 1000% where as the electrical conductivity increased by 13 orders of magnitude with the presence of 50 wt% GNP fillers. The morphology of the composites was analyzed using SEM micrographs to observe the dispersion of filler within the matrix. These thermally conductive composites represent potential cost-effective materials to injection mold three-dimensional, net-shape microelectronic enclosures with superior heat dissipation performance.

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Study on the ALN Thin Film for Improving the Performance of Heat Dissipation on High Power LED Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.613 ◽

2013 ◽

Vol 834-836 ◽

pp. 613-616 ◽

Cited By ~ 2

Author(s):

Yang Li ◽

Chen Kui ◽

Hui Ren Peng ◽

Ming Jia Zhu ◽

Ya Wen Pan ◽

...

Keyword(s):

Thin Film ◽

Magnetron Sputtering ◽

Direct Current ◽

High Power ◽

Heat Dissipation ◽

Aluminum Substrate ◽

Back Side ◽

Dc Magnetron Sputtering ◽

High Power Led ◽

Thermally Conductive

This dissertation employs the method of direct current (DC) magnetron sputtering on the reverse side of the high power LED aluminum substrate to deposit the AlN thin film. And then, we paste the high power LED beads to the front of the substrate, testing and studying the heat dissipation influences of the AlN thin film on the high-power LED beads. In order to compare easily, some parts of the reverse of aluminum substrate should be overlaid thermally conductive silicone. The result indicates that depositing the AIN thin film or the overlay thermally conductive silicone on the back side of the aluminum substrate can improve the heat dissipation capability of high power LED, the AIN thin film especially.

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Improved Heat Dissipation of High-Power LED Lighting by a Lens Plate with Thermally-Conductive Plastics

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2018.14950 ◽

2018 ◽

Vol 18 (3) ◽

pp. 1909-1912 ◽

Cited By ~ 1

Author(s):

Dong Kyu Lee ◽

Hyun Jung Park ◽

Yu-Jung Cha ◽

Hyeong Jin Kim ◽

Joon Seop Kwak

Keyword(s):

High Power ◽

Heat Dissipation ◽

Led Lighting ◽

High Power Led ◽

Thermally Conductive ◽

Conductive Plastics

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OPTIMIZATION OF BIMODAL QUANTUM DOTS CONVERTED WHITE LEDS FOR HIGH COLOUR RENDITION

PROCEEDINGS OF CIE 2018 TOPICAL CONFERENCE ON SMART LIGHTING ◽

10.25039/x45.2018.pp24 ◽

2018 ◽

Author(s):

Yunzhuo Wang ◽

Qi Yao

Keyword(s):

Quantum Dots ◽

White Leds

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Highly thermally conductive graphene-based electrodes for supercapacitors with excellent heat dissipation ability

Sustainable Energy & Fuels ◽

10.1039/c7se00399d ◽

2017 ◽

Vol 1 (10) ◽

pp. 2145-2154 ◽

Cited By ~ 7

Author(s):

Bo Zhao ◽

Xian-Zhu Fu ◽

Rong Sun ◽

Ching-Ping Wong

Keyword(s):

Heat Dissipation ◽

Cycling Performance ◽

Thermally Conductive ◽

Rate Capacity ◽

Electrodes For Supercapacitors

The highly thermally conductive graphene-based electrodes for supercapacitors exhibit great heat dissipation ability as well as excellent cycling performance and rate capacity.

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Highly thermally conductive UHMWPE/NG composites with the segregated structure and their application for heat spreader

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705720965649 ◽

2020 ◽

pp. 089270572096564

Author(s):

Xiao Wang ◽

Hui Lu ◽

Jun Chen

Keyword(s):

Thermal Conductivity ◽

Laser Flash ◽

Heating Process ◽

X Ray Diffraction ◽

Heat Spreader ◽

Conductive Composites ◽

Compression Direction ◽

Thermal Analyzer ◽

Thermally Conductive ◽

Plane Direction

In this work, ultra-high molecular weight polyethylene (UHMWPE)/natural flake graphite (NG) polymer composites with the extraordinary high thermal conductivity were prepared by a facile mixed-heating powder method. Morphology observation and X-ray diffraction (XRD) tests revealed that the NG flakes could be more tightly coated on the surface of UHMWPE granules by mixed-heating process and align horizontally (perpendicular to the hot compression direction of composites). Laser flash thermal analyzer (LFA) demonstrated that the thermal conductivity (TC) of composites with 21.6 vol% of NG reached 19.87 W/(m·K) and 10.67 W/(m·K) in the in-plane and through-plane direction, respectively. Application experiment further demonstrated that UHMWPE/NG composites had strong capability to dissipate the heat as heat spreader. The obtained results provided a valuable basis for fabricating high thermal conductive composites which can act as advanced thermal management materials.

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Analysis on High-Power Seaport LED Luminaire with Uniform Light Distribution Based on Optimized Lens and Heatsink

Applied Sciences ◽

10.3390/app11094035 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4035

Author(s):

Jinsheon Kim ◽

Jeungmo Kang ◽

Woojin Jang

Keyword(s):

Light Source ◽

High Power ◽

Heat Dissipation ◽

Light Emitting Diode ◽

Light Distribution ◽

Light Sources ◽

Led Light ◽

High Power Led ◽

Distribution Requirement ◽

Lighting Application

In the case of light-emitting diode (LED) seaport luminaires, they should be designed in consideration of glare, average illuminance, and overall uniformity. Although it is possible to implement light distribution through auxiliary devices such as reflectors, it means increasing the weight and size of the luminaire, which reduces the feasibility. Considering the special environment of seaport luminaires, which are installed at a height of 30 m or more, it is necessary to reduce the weight of the device, facilitate replacement, and secure a light source with a long life. In this paper, an optimized lens design was investigated to provide uniform light distribution to meet the requirement in the seaport lighting application. Four types of lens were designed and fabricated to verify the uniform light distribution requirement for the seaport lighting application. Using numerical analysis, we optimized the lens that provides the required minimum overall uniformity for the seaport lighting application. A theoretical analysis for the heatsink structure and shape were conducted to reduce the heat from the high-power LED light sources up to 250 W. As a result of these analyses on the heat dissipation characteristics of the high-power LED light source used in the LED seaport luminaire, the heatsink with hexagonal-shape fins shows the best heat dissipation effect. Finally, a prototype LED seaport luminaire with an optimized lens and heat sink was fabricated and tested in a real seaport environment. The light distribution characteristics of this prototype LED seaport luminaire were compared with a commercial high-pressure sodium luminaire and metal halide luminaire.

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Crystalline borophene quantum dots and their derivative boron nanospheres

Materials Advances ◽

10.1039/d1ma00124h ◽

2021 ◽

Author(s):

Huiqi Wang ◽

Duo An ◽

Mei Wang ◽

Liwen Sun ◽

Ying Li ◽

...

Keyword(s):

Quantum Dots ◽

Hydrazine Hydrate ◽

High Power ◽

Photoluminescence Properties ◽

Chemical Exfoliation ◽

One Step

Crystalline borophene quantum dots with two-photo fluorescence and their derivative boron nanospheres with hydrazine hydrate-dependent photoluminescence properties were prepared by efficient high-power sonication method combined with chemical exfoliation and one-step...

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Electromagnetic Field Analysis and Design of a Hermetic Interior Permanent Magnet Synchronous Motor with Helical-Grooved Self-Cooling Case for Unmanned Aerial Vehicles

Applied Sciences ◽

10.3390/app11114856 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4856

Author(s):

Hae-Sol Lee ◽

Myeong-Hwan Hwang ◽

Hyun-Rok Cha

Keyword(s):

Electromagnetic Field ◽

Unmanned Aerial Vehicles ◽

Permanent Magnet ◽

High Power ◽

Heat Dissipation ◽

Power Source ◽

Flight Duration ◽

Aerial Vehicles ◽

Drive Motor ◽

Interior Permanent Magnet

As unmanned aerial vehicles expand their utilization and coverage, research is in progress to develop low-weight and high-performance motors to efficiently carry out various missions. An electromagnetic field interior permanent magnet (IPM) motor was designed and analyzed in this study that improved the flight performance and flight duration of an unmanned aerial vehicle (UAV). The output power and efficiency of a conventional commercial UAV motor were improved by designing an IPM motor of the same size, providing high power output and high-speed operation by securing high power density, wide speed range, and mechanical stiffness. The cooling performance and efficiency of the drive motor were improved without requiring a separate power source for cooling by introducing the helical-grooved self-cooling case, which has a low heat generation structure. Furthermore, the motor is oil-cooled through rotating power without a separate power source, reducing the weight of the UAV. The heat dissipation characteristics were verified by fabricating a prototype and taking actual measurements to verify the validity of the heat dissipation characteristics. The results of this study are expected to improve the flight duration and performance of UAVs and contribute to the efficiency of the design of a UAV drive motor.

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