摘要
针对LED散热冷却问题,研究了一种自然对流条件下竖直放置对称阵列斜翅热沉的换热性能,分析了翅片高度、纵向间距对换热性能的影响,讨论了对称阵列斜翅热沉换热特点.结果表明:努塞尔数随瑞利数增加而线性增大;当热沉翅片高度大于40 mm时,努塞尔数达到最大值;随后努塞尔数随翅片高度增加不再明显变化.翅片纵向间距从25 mm到15 mm,其间距愈短,努塞尔数下降的愈快;从四列热沉到八列热沉,基板温度场自下而上分层现象愈来愈明显,高温区域集中在基板上部两角位置.相对四列热沉和八列热沉,六列热沉瑞利数随努塞尔数变化的拟合曲线斜率要比四列热沉高约5%,其具有更少的高温区域,有效地改善换热性能.
Aiming at the cooling problem of light emitting diode(LED),the heat transfer performance of inclined finned heat sinks that are placed vertically with symmetrical arrays under natural convection was studied.The influence of fin height and longitudinal spacing on the heat transfer performance was analyzed,and the heat transfer characteristics of heat sinks with symmetric inclined fin arrays were discussed.The results show that the Nusselt number increases linearly with the increase of Rayleigh number.When the height of fins exceeds 40 mm,Nusselt number reaches its maximum value,and then it does not change significantly with the increase of the height of heat sinks.The longitudinal spacing of the fins is from 25 mm to 15 mm,the shorter the spacing,the faster the Nusselt number drops.From four-row heat sinks to eight-row heat sinks,the phenomenon of temperature field stratification of the base from bottom to top is becoming more and more significant,and the high temperature zones are concentrated on the upper corner of the base.Compared with four-row heat sinks and Eight-row heat sinks,the slope of fitting curve of six-row heat sinks with Nusselt number is about 5%higher than that of four-row heat sinks,which has fewer high temperature zones and can effectively improve heat transfer performance.
作者
赵俊志
严融融
张莹
宋本哲
陈润果
ZHAO Jun-zhi;YAN Rong-rong;ZHANG Ying;SONG Ben-zhe;CHEN Run-guo(School of Mechanical and Electrical Engineering,Nanchang University,Nanchang 330000,China)
出处
《科学技术与工程》
北大核心
2019年第22期155-161,共7页
Science Technology and Engineering
基金
国家自然科学基金(11562011,51566012)资助
关键词
自然对流
斜翅热沉
换热性能
数值模拟
natural convection
inclined finned heat sink
heat transfer performance
numerical simulation
