Abstract

Microstructures of wicks have been widely investigated on their performances of heat and mass transfer and various structures have been attempted. As have been optimized by the nature, the microstructures inside plants may also be applied on the wick structure. In this paper, four substomatal cavity structures are chosen to investigate the influence of the structural parameters on the diffusional resistance by using Fick's first law of diffusion and the equation of mass conservation comprehensively. The result indicates that both the shape and parameters affect the diffusion, and the sphere cavity structure presents the lowest diffusional resistance because of its smoothest surface. Based on the result of the comparison, the sphere is chosen as the optimal structure of the substomatal cavity and applied on the design of the microstructure of wick. In order to analyze the performances of the substomatal cavity inspired wick structure with fractal network microchannels and sphere cavity, comparisons with the leaf vein inspired wick structure with fractal network microchannels and micro fin-pins are conducted. It is obvious to find that the substomatal cavity inspired structure is promising in the application on wick structure because of its good performances of heat and mass transfer.

摘要

灯芯的微观结构已被广泛研究其传热和传质性能，并尝试了各种结构。正如大自然所优化的那样，植物内部的微结构也可以应用在灯芯结构上。本文选取四种气孔下腔结构，综合运用Fick扩散第一定律和质量守恒方程，研究结构参数对扩散阻力的影响。结果表明，形状和参数都影响扩散，球腔结构由于其表面最光滑而呈现出最低的扩散阻力。根据比较结果，选择球体作为气孔下腔的最佳结构，并应用于灯芯微结构的设计。为了分析具有分形网络微通道和球腔的气孔下腔启发芯结构的性能，与具有分形网络微通道和微鳍针的叶脉启发芯结构进行了比较。很明显，气孔下腔结构因其良好的传热传质性能而在灯芯结构上的应用前景广阔。