Heat transfer performance testing of a new type of phase change heat sink for high power light emitting diode

Abstract

In view of the limitations of solid metal heat sink in the heat dissipation of high power light emitting diode (LED), a kind of miniaturized phase change heat sink is developed for high power LED packaging. First, the fabrication process of miniaturized phase change heat sink is investigated, upon which all parts of the heat sink are fabricated including main-body and end-cover of the heat sink, the formation of three-dimensional boiling structures at the evaporation end, the sintering of the wick, and the encapsulation of high power LED phase change heat sink. Subsequently, with the assistance of the developed testing system, heat transfer performance of the heat sink is tested under the condition of natural convection, upon which the influence of thermal load and working medium on the heat transfer performance is investigated. Finally, the heat transfer performance of the developed miniaturized phase change heat sink is compared with that of metal solid heat sink. Results show that the developed miniaturized phase change heat sink presents much better heat transfer performance over traditional metal solid heat sink, and is suitable for the packaging of high power LED.

摘要

针对现有固态金属热沉在大功率LED 散热方面的局限性, 设计并制造了一款微型相变热沉。 首先, 研究了该微型相变热沉的加工工艺, 包括热沉本体和端盖的加工、蒸发端面三维沸腾结构成形、 吸液芯烧结以及相变热沉的封装。然后, 基于开发的测试系统, 对相变热沉在自然对流环境下进行传 热性能测试, 研究了热载荷和工质对传热性能的影响。最后, 将该相变热沉的传热性能与固态金属热 沉进行比较。研究结果表明, 该相变热沉具有很好的传热性能, 且适用于大功率LED 的封装。