随着机械电子设备的不断发展，热管理问题面临越来越严重的挑战，为解决此问题，根据仿生学原理，以天鹅绒竹芋表面微观凸起结构为设计依据，以纳米尺度铜粉为材料烧结制备锥形毛细芯，构造新型平板热管，并以去离子水为工质对其热性能进行研究。研究加热功率、平板热管放置角度及毛细芯氧化与未氧化等因素对平板热管传热特性的影响。结果表明，由于锥形毛细芯多尺度孔隙结构的存在，不仅实现蒸汽从大尺度孔隙逸出，液体从小孔隙吸入，而且缩短了液体流动路径，减小了流动阻力，同时扩大了换热面积，因此大大提高了平板热管的传热性能。锥形毛细芯平板热管具有较好的传热性能及抗重力特性。毛细芯经氧化处理后可显著减小平板热管的换热热阻，提高平板热管的传热性能，在热流密度为107.1 W/cm2时，其总热阻最小值为0.079 K/W。
With the development of mechanical and electronic equipments, thermal management problem becomes more and more challenging. In order to solve this problem, according to the bionics principle, a new structure flat heat pipe(FHP), based on the micro structure of the Calathea zebrine, using nano-scale copper powder as sintered material, is constructed with conical capillary wicks, and its thermal performance is investigated experimentally with deionized water used as the working fluid. The effect of heating power, inclination angle and capillary wicks through oxidation on thermal performance of the FHP are studied. The results show that the existence of the multi-scale pore gap of the conical capillary wicks not only realized the vapor escape from large pore gap and liquid suck from small pore gap, but also shortened the liquid flow path, and reduced the flow resistance, as well as expanded the heat transfer area, thus greatly improved the heat transfer performance of the FHP. The new structure FHP has good thermal and anti-gravity performance. Capillary wicks through oxidation can significantly reduce the FHP’s thermal resistance, improving its thermal performance, and its minimum total thermal resistance is equal to 0.079 K/W when the heat flux reaches to 107.1 W/cm2.
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