Numerical analysis of a vertical double-pipe single-flow heat exchanger applied in an active cooling system for high-power LED street lights

Schmid, Gerd; Huang, Zun-Long; Yang, Tai-Her; Chen, Sih‐Li

doi:10.1016/j.apenergy.2017.03.054

Cited by 18 publications

(4 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The power of LED street lighting is usually less than 0.25 kW [30][31][32], and the power of slow charging for EV is 7 kW (220 V × 32 A, which is equivalent to the C-rate of 0.1C~0.45C) or more. Therefore, the power of the EV charging poles should be primary part of the capacity of the hybrid poles group.…”

Section: The Efficiency Model Of Smart Hybrid Poles Group Approachmentioning

confidence: 99%

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

et al. 2018

View full text Add to dashboard Cite

Energy crisis and environmental pollution have become global problems, and the increasing use of energy has caused climate change. Electric vehicle (EV) is regarded as the future of the automotive industry, because of the lesser impact on the environment than traditional vehicles. In recent years, electric vehicles have developed rapidly. However, the development of charging points and service cannot adapt to the development trend of EV. In urban areas, the distribution characteristics of street lighting and charging points are similar. Therefore, the street lighting pole with EV charging is proposed. However, due to the capacity limit of public grid, the single hybrid pole is only suitable for slow charging. This paper proposes hybrid poles group based on renewable energy, street lighting, and EV charging, which can realize fast charging and slow charging based on DC micro-grid with help of energy storage device. For studying the suitable number in a group of smart hybrid pole, the efficiency model of smart hybrid poles group is proposed. The efficiency model indicates that the group approach has better performance than the single pole, which provides a theoretical basis for practical construction.Energies 2018, 11, 3445 2 of 17 of car to pole is about 8:1, so it is less than the theoretical ratio of 1:1~1.2. Currently, it needs to build more charging poles [6]. In 2020, 435 thousand charging points will be built in Beijing to satisfy the requirement for 600 thousand EV. Moreover, the lack of an adequate publicly accessible charging infrastructure is considered to be a major obstacle to the growth of European market [15].Charging facilities generally include private points and charging station. In recent years, it has been suggested that EV charging points can be integrated with the existing street lighting network, because the distribution characteristic of street lighting in the urban area is similar with the distribution characteristic of charging points. Therefore, the street lighting pole with EV charging system is presented [16]. Smith et al. introduced the concept of a DC Lighting and Charging network to increase the power transfer capability of the lighting cables in order to enable charging of EVs at a higher energy efficiency than AC [16]. In addition, BMW and Ubitricity company, respectively, have deployed a street-light charging solution [17,18], which contribute to a greener city. However, this single street-light charging pole is only suitable for EV slow charging because the power of public grid for a single pole is not enough for EV fast charging.For handling the incompatibility between fast charging and the power limit, the hybrid poles group method with renewable energy, street lighting, and EV charging systems are proposed based on DC micro-grid in this paper. The energy storage devices in hybrid poles group can collaboratively work with the help of DC micro-gird and provide enough electric power for fast charging.The remainder of the paper is organized as follows: Section 2 presents the archi...

show abstract

Section: The Efficiency Model Of Smart Hybrid Poles Group Approachmentioning

confidence: 99%

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Even a 10 °C-15 °C increase in junction temperature reduces the package lifetime by 50%. [8][9][10] In addition, if the heat generated from the LED device is not properly released, both the lifetime and the light emission efficiency is reduced. [11][12][13] Flip-chip (FC) LED packages have been actively studied to solve the above problems.…”

Section: Introductionmentioning

confidence: 99%

Effect of (Ni, Au)₃Sn₄ growth on the thermal resistance of Au-20 wt% Sn solder/ENIG joint in flip-chip LED packages

Lee

Kang

Yoo

et al. 2020

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

In this study, the effect of growth of intermetallic compound (IMC) layer between Au-20 wt% Sn solder and electroless Ni/immersion Au (ENIG) on the thermal resistance of a flip-chip (FC) light emitting diode (LED) package was investigated. Two IMC layers were formed at the interface of FC LED package, including Au5Sn and (Ni, Au)3Sn4 that were identified using a transmission electron microscopy. A thermal aging test was carried out at 200 °C for 1000 h to observe IMCs growth. After 1000 h, the (Ni, Au)3Sn4 thickness increased to about 1.5 μm and the thermal resistance of the FC LED package increased by 3.5 times compared to the initial thermal resistance of 2 K W−1. As the (Ni, Au)3Sn4 grew, a calculation of thermal resistance also increased comparing to the initial aging test, thus, the growth of (Ni, Au)3Sn4 layer can be effective factor on the increase of thermal resistances of FC LED package.

show abstract

“…This is because of their unparalleled advantages over traditional light sources, such as long lifetime, lower power consumption with higher luminous efficiency, low maintenance, small package and environmental friendliness, etc. (Huang and Wang, 2017; Chung et al , 2014; Tang et al , 2017; Schmid et al , 2017). The performances of LED lamps have allowed them to be the solution for lighting requirement, replace traditional lamps and become leading lighting fixture in the future.…”

Section: Introductionmentioning

confidence: 99%

Qualitative analysis of coupling effect of fluid velocity distribution in microchannels on the performance of the LED water cooling system

Chen

Hou

Xiaochao

2019

HFF

View full text Add to dashboard Cite

Purpose The purpose of this paper is to ensure adequate thermal management to remove and dissipate the heat produced by a light-emitting diode (LED) and to guarantee reliable and safe operation. Design/methodology/approach A three-dimensional (3-D) computational fluid dynamics (CFD) model was used to analyze the distribution of fluid velocities among microchannels at four different aspect ratios. Findings The results showed that at the same inlet flow rate, the larger the aspect ratio of the microchannels, the better the uniformity of the internal fluid velocity and thus better the heat dissipation performance on the surface of the high-power LED chip. In addition, the thermal performance of a high-power LED water cooling system with four different aspect ratios’ microchannel structures is further studied experimentally. Specifically, the coupling effect between the fluid velocity distribution in the microchannels and the heat dissipation performance of a high-power LED water cooling system is qualitatively analyzed and compared with the simulation results of the fluid velocity distribution. The results fully demonstrated that a larger aspect ratio of the microchannels results in better heat dissipation performance on the surface of the high-power LED chip. Originality/value Optimizing the structural parameters to facilitate a relatively uniform velocity distribution to improve the water cooling system performance may be a key factor to be considered.

show abstract

Numerical analysis of a vertical double-pipe single-flow heat exchanger applied in an active cooling system for high-power LED street lights

Cited by 18 publications

References 30 publications

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

Effect of (Ni, Au)₃Sn₄ growth on the thermal resistance of Au-20 wt% Sn solder/ENIG joint in flip-chip LED packages

Qualitative analysis of coupling effect of fluid velocity distribution in microchannels on the performance of the LED water cooling system

Contact Info

Product

Resources

About

Numerical analysis of a vertical double-pipe single-flow heat exchanger applied in an active cooling system for high-power LED street lights

Cited by 18 publications

References 30 publications

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

A Group Approach of Smart Hybrid Poles with Renewable Energy, Street Lighting and EV Charging Based on DC Micro-Grid

Effect of (Ni, Au)3Sn4 growth on the thermal resistance of Au-20 wt% Sn solder/ENIG joint in flip-chip LED packages

Qualitative analysis of coupling effect of fluid velocity distribution in microchannels on the performance of the LED water cooling system

Contact Info

Product

Resources

About

Effect of (Ni, Au)₃Sn₄ growth on the thermal resistance of Au-20 wt% Sn solder/ENIG joint in flip-chip LED packages