以某中等功率LED灯具为例, 设计了塑料散热器的基本构型。采用数值仿真的办法对散热器的性能进行分析, 并根据分析结果进行结构改进与优化。结果表明, 在同样构型下塑料散热器散热性能低于铝合金散热器; 与传统铝合金散热器不同, 当肋片高度达到30 mm后, 塑料散热器的散热能力趋于稳定; 虽然导热塑料的红外发射率较高, 仿真分析表明通过热辐射散出的热能只占总热很小的一部分, 所以塑料散热器的设计应以增加对流换热面积为主, 增加肋片与环境的视角系数是次要考虑因素。改进优化后的塑料散热器达到了和铝合金散热器相近的散热性能, 总质量较铝合金散热器减轻了30%, 验证了塑料散热器在降低产品重量方面的优越性。

Taking a medium power LED lamp as an example, the basic configuration of the plastic radiator was designed. The performance of the radiator was analyzed by numerical simulation, and the structure was improved and optimized according to the analytical results. The results show that the thermal dissipating capacity of the Al alloy radiator is better than the plastic radiator when they have the same configuration. Different from the traditional aluminum alloy radiator, the heat dissipating capacity of the radiator plastic tends to be stable when the fins are higher than 30 mm. Although the infrared emission rate of the conductive plastic is as high as 0.9, the thermal energy dissipated through thermal radiation is very small, which means the plastic radiator design should be prior to increasing the convective heat exchange area. The thermal dissipation capacity of the optimized plastic radiator is quite close to that of the Al alloy radiator, and its weight is reduced 30% of the aluminum alloy radiator, which verifies the superiority of the plastic radiator product.