Guzej Michal, Zachar Martin, Kominek Jan, Kotrbacek Petr, Brachna Robert
Heat Transfer and Fluid Flow Laboratory, Faculty of Mechanical Engineering, Brno University of Technology (BUT), Technicka 2896, 616 69 Brno, Czech Republic.
Polymers (Basel). 2021 Apr 7;13(8):1186. doi: 10.3390/polym13081186.
Polymers with highly conductive fillers could possibly replace standardly used materials, such as aluminum and copper alloys, for passive cooling purposes. The main problem of the composite polymer-based heat sinks is that their high thermal conductivity is uneven. The orientation of this anisotropy is set according to the position of the highly thermally conductive filler. Its orientation is influenced by the melt flow during the polymer heat sink molding process. This article shows that change of the melt flow inside the mold cavity can improve the overall cooling efficiency of a polymer heat sink, which leads to lower temperatures on the heat source used. Two polymer heat sinks of identical geometries were produced. Their high thermal conductivity was given by the use of graphite flakes as the filler. The only difference between the heat sinks was in the position of the fan gate during their production. Different temperatures of the heat source between the two heat sinks were observed for the same measurement conditions. The measurements were conducted at Heatlab, BUT.
具有高导电性填料的聚合物有可能替代标准使用的材料，如铝合金和铜合金，用于被动冷却目的。基于复合聚合物的散热器的主要问题是其高导热率不均匀。这种各向异性的方向根据高导热填料的位置而定。其方向受聚合物散热器成型过程中熔体流动的影响。本文表明，模腔内熔体流动的变化可以提高聚合物散热器的整体冷却效率，从而降低所用热源的温度。制作了两个几何形状相同的聚合物散热器。它们的高导热率是通过使用石墨片作为填料实现的。散热器之间的唯一区别在于生产过程中风扇浇口的位置。在相同的测量条件下，观察到两个散热器之间热源的不同温度。测量在布尔诺理工大学的热实验室进行。
