中文摘要：

LED作为第四代照明光源应用于汽车照明已经是一种必然的趋势。针对汽车照明用LED散热问题,提出了一种以铜粉烧结块为吸液芯的铜-水复合冷凝段重力式热管（HP）散热系统,并且实验研究了冷凝侧对流换热系数、LED粘结材料导热系数以及热管充液率对芯片结温的影响。结果表明：1）对流换热系数与芯片结温呈负相关,并且在对流换热系数增加到50-70 W/m^2K之间时,芯片结温下降趋于平稳;2）LED粘结材料的导热系数越大（≥100 W/m·K）,越有利于降低芯片结温;3）加热功率偏小（≤3 W）时,充液率为50%时最利于降低芯片结温,加热功率偏大（≥5 W）时,充液率为60%最为合适。

英文摘要：

LED, a fourth generation lighting source, used in automotive lighting is an inevitable trend. As for the heat dissipation problem of automotive lighting LED, this paper puts forward a copper powder sintering as a wick of copper-water gravity heat pipe （HP） and experimentally research the effect of convective coefficient, coefficient of thermal conductivity and charging rate on junction temperature respectively. The results showed that： 1） convective coefficient is negatively correlated with junction temperature, and when the convective coefficient reaches to 50 - 70 W/m2K, the junction temperature gets a smooth trend; 2） the greater the coefficient of thermal conductivity （≥100 W/m· K） is, the faster the junction temperature reduce; 3） when the heating power is less than 3 W, the optimal filling ratio is 50% and when the heating power is greater than 5 W, the optimal filling ratio is 60%.