中圖分類號： TN312.8 文獻標識碼： A DOI：10.16157/j.issn.0258-7998.191302 中文引用格式： 饒剛，楊東恒，王威. COB-LED廠房燈翅片偏轉(zhuǎn)角對散熱性能影響研究[J].電子技術(shù)應(yīng)用，2020，46(5)：102-106. 英文引用格式： Rao Gang，Yang Dongheng，Wang Wei. Effecting study of the radiator fin deflecting angle to COB-LED workshop lamp on the heat dissipation performance[J]. Application of Electronic Technique，2020，46(5)：102-106.
Effecting study of the radiator fin deflecting angle to COB-LED workshop lamp on the heat dissipation performance
Rao Gang，Yang Dongheng，Wang Wei
Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering，Wuhan University of Science and Technology， Wuhan 430081，China
Abstract： A straight fin radiator was designed for dissipating the working heat of a circular LED lighting-source. According to thermal simulation analysis to straight fin radiator on ANSYS Icepak, it was found that there was high temperature agglomeration in the center of straight fin radiator. In order to solve the problem of temperature accumulation in the center of the radiator, the fin curve was established by the polar coordinate point fitting method, and the linear fin radiator was improved to the curve fin radiator. Six kinds of curved fin models with different deflection angles were established and simulated. The results show that when the radiator fin deflection angle is 40°, the temperature of the chip is the lowest, the effect of radiator temperature equalization is the best, and the weight of radiator is reasonable. The temperature error between simulation and measurement is less than 4%, which verifies the rationality of the research.
Key words : circular LED light source；curved fin；deflection angle；radiator；thermal simulation analysis
0 引言
COB(chip on board)-LED是將多個LED晶元芯片封裝在同一塊基板上，實現(xiàn)光源的模塊化以便于生產(chǎn)安裝。COB-LED具有光效高、光照均勻等優(yōu)點，但是這種光源在工作時熱流密度大，如果晶元芯片產(chǎn)生的熱量無法通過散熱器有效導(dǎo)出到環(huán)境中，則會造成晶元芯片的結(jié)溫升高、光強下降及使用壽命縮短等問題，從而影響燈具的性能[1-2]。COB-LED廠房燈主要采用自然對流散熱，該散熱方式只需在光源上安裝散熱器，無需添加風冷或者液冷裝置，更加節(jié)能環(huán)保[3]。
目前對于圓形COB-LED光源的散熱，主要采用圓形底板散熱器。散熱器翅片主要為直翅片，布局方式為平行式布局和發(fā)散式布局，周旭等人的研究表明發(fā)散式布局散熱效果優(yōu)于平行式布局[4]。但是這種直翅片散熱器翅片間氣體流動均勻，不利于強化換熱。為增強自然對流散熱，PARK S J等人采用在圓形底板上添加中空圓柱，然后在圓柱表面添加開縫翅片布局方式[5]。對翅片進行交錯式布局或改變翅片放置角度來增強自然對流散熱[6-7]。為增強圓形底板散熱器中心散熱效果，Schmid等在散熱器中心進行開孔設(shè)計增強散熱器中心的對流換熱，對開孔直徑和高度進行優(yōu)化[8]。以往的研究都是對直翅片尺寸和散熱器布局進行優(yōu)化解決LED溫升問題，并沒有從翅片偏轉(zhuǎn)角研究LED散熱器的均溫和散熱性能。本文以初步設(shè)計的50 W COB-LED廠房燈直線式翅片散熱器為基礎(chǔ)，改變傳統(tǒng)的散熱器優(yōu)化方式，運用極坐標點擬合法改變翅片的偏轉(zhuǎn)角度，以增強散熱器均溫和散熱效果。對比分析不同偏轉(zhuǎn)角翅片散熱器的底板溫度、翅片間空氣流動特性。以晶元芯片工作溫度、散熱器熱阻、散熱器質(zhì)量等參數(shù)作為散熱器優(yōu)劣的評判參數(shù)，通過對不同偏轉(zhuǎn)角度散熱器模型進行熱仿真分析、對比，從而確定出最佳翅片偏轉(zhuǎn)角度[9]。
