大功率LED分段翅片散热器热设计

Thermal design of discrete plate fin heat sink for high-power LED

针对平板翅片式散热器存在的不足,提出一种分段翅片散热器。基于COMSOL Multiphysics平台,对不同分段数的分段翅片散热器的流动传热过程进行模拟。在此基础上,将Matlab模糊推理工具箱与Simulink相结合,对不同结构的散热器进行可靠性评估。最终得到分段数为4的散热器换热系数最大、可靠性最高、结构最佳,每段翅片长度、厚度、高度、翅片间距及分段间隔分别为29 mm,4 mm,40 mm,10 mm和3 mm。当入口风速由1 m/s增大到9 m/s,分段数为4翅片散热器的换热系数相对于平直翅片散热器提高了3.42%~5.47%,压降增大了31.60%~40.85%,可靠性提高了0.2。此研究为散热器结构的优化设计提供了理论依据和参考。

Aiming at the insufficiency of the flat plate fin heat sink,a discrete plate fin heat sink is proposed.The flowingheat transfer process of the discrete plate fin heat sink with different segments is simulated on the basis of COMSOL Multiphys-ics platform.On this basis,the Matlab fuzzy inference toolbox is combined with Simulink to evaluate the reliability of heat sinkswith different structures.It is obtained that the heat sink with four segments has the maximum heat transfer coefficient,highestreliability,and optimal structure.The fin length,thickness,height,space and subsection gap are29mm,4mm,40mm,10mmand3mm respectively.When the wind speed at inlet is increased from1m/s to9m/s,in comparison with the flat plate fin heatsink,the heat transfer coefficient of the discrete plate fin heat sink with four segments is increased by3.42%~5.47%,its pres-sure drop is increased by31.60%~40.85%,and its reliability is increased by20%.This study provides the theoretical basis anda reference for optimization design of the heat sink structure.