Convective heat dissipation with lattice-frame materials
Convective heat dissipation with lattice-frame materials
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DOI：
10.1016/j.mechmat.2003.07.001
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发表时间：
2004-08-01
影响因子：
3.9
通讯作者：
Hodson, HP
中科院分区：
文献类型：
--
作者：
Kim, T;Zhao, CY;Hodson, HP
本文介绍了一种由全三角形、轻质（孔隙率约为0.938）铝网格框架材料（LFM）制成的紧凑型散热器的传热和压降实验结果。由于LFM固有的结构各向异性，选择两个相互垂直的方向进行测量。在稳态条件下，恒定的热通量施加到散热器，并通过强制空气对流消散。实验数据进行了比较，从基于鳍类比的分析模型预测。实验结果表明，压降强烈依赖于结构的取向，主要是由于流动阻塞效应。对于传热测量，在恒定热流条件下的基板上的典型局部温度分布被捕获与红外相机。LFM的热行为被发现密切遵循的气缸组，与早期过渡雷诺数（基于支柱直径）等于约300。从鳍类比的努塞尔数预测与实验测量，除了在低雷诺数略有低估观察。与空通道和常用的热交换器介质的比较表明，本LFM散热器可以去除热量的效率比空通道高约7倍，并且在相同的孔隙率水平下与气缸组一样有效。铝合金LFM非常坚硬和坚固，使其成为需要散热和机械承载能力的多功能结构的理想选择。(C)2003 Elsevier Ltd.保留所有权利。
This paper presents experimental results on heat transfer and pressure drop for a compact heat sink made of fully triangulated, lightweight (porosity similar to0.938), aluminum lattice-frame materials (LFMs). Due to the inherent structural anisotropy of the LFMs, two mutually perpendicular orientations were selected for the measurements. Constant heat flux was applied to the heat sink under steady state conditions, and dissipated by forced air convection. The experimental data were compared with those predicted from an analytical model based on fin analogy. The experimental results revealed that pressure drop is strongly dependent upon the orientation of the structure, due mainly to the flow blockage effect. For heat transfer measurements, typical local temperature distributions on the substrate under constant heat flux conditions were captured with infrared camera. The thermal behavior of LFMs was found to follow closely that of cylinder banks, with early transition Reynolds number (based on strut diameter) equal to about 300. The Nusselt number prediction from the fin-analogy correlates well with experimental measurements, except at low Reynolds numbers where a slightly underestimation is observed. Comparisons with empty channels and commonly used heat exchanger media show that the present LFM heat sink can remove heat approximately seven times more efficient than an empty channel and as efficient as a bank of cylinders at the same porosity level. The aluminum LFMs are extremely stiff and strong, making them ideal candidates for multifunctional structures requiring both heat dissipation and mechanical load carrying capabilities. (C) 2003 Elsevier Ltd. All rights reserved.