为了解决大功率LED散热问题,构建了包括LED固体部件及外部流体空间的三维数学模型。基于有限元法,应用k-ε模型模拟自然对流换热条件下LED模组散热情况。模拟结果表明,LED模组温度场分布不均,芯片结温较高;受芯片功率密度及位置布设的影响,中心翅片的散热效果差。通过改变散热器结构,设计了两种翅片组合形式,虽然换热面积有所减少,但由于中心翅片的对流换热得到强化,达到了降低结温的效果,提高了散热性能。
A three-dimensional mathematical model of LED hardware and external fluid space was established to solve the problem of heat dissipation of high-power LED. Based on numerical methods of finite element method, the heat dissipation performance of LED model was simulated by k-ε model under natural convection. The result shows that the temperature field distribution of LED models is inhomogeneous and the chip presents to be at a higher temperature. In the meanwhile, influenced by the chip power density and position setting, heat dissipation effect of the center fins is poor. In this case, two forms of fin combination by structure changing of radiator were designed. Despite of the reducing of heat exchange area, heat convection of central fins is intensified, which enhances the capability of heat dissipation and reduces the junction temperature.