面向薄膜沸腾传热的仿生拓扑表面毛细传输研究

为提高表面结构毛细极限,强化毛细供液薄膜沸腾传热性能,通过纳秒脉冲激光加工的熔凝和相爆炸效应在金属钛表面加工出具有微颗粒结构的微沟槽阵列,并采用基于敞式微沟槽流阻模型修正的毛细传输特性系数进行毛细传输能力表征。研究结果表明,纳秒脉冲激光加工的微颗粒结构显著提高了微沟槽超亲液性和工质毛细传输能力;毛细传输特性系数随微沟槽宽度减小而增大,且在沟槽底部加工次级微沟槽可获得仿红瓶子草绒毛的跨尺度超亲液分层微沟槽阵列,形成独特分层毛细传输模式,进一步提高毛细极限。

Capillary Liquid Transport on Biomimetic Topological Surfaces for Film Boiling Heat Transfer

 In order to improve the capillary limit of surface structures for enhancing capillary-fed film boiling heat transfer, the microgroove arrays overlaid with microparticle structures were fabricated on titanium substrates by taking advantages of melting and solidification, and phase explosion of nanosecond pulsed lasers. A modified capillary liquid transport characteristic coefficient was developed to characterize the capillary liquid transport capability of the fabricated microgrooves based on flow resistance in open microgrooves model. The results show that the microparticle structures obtained during laser ablation improve the superhydrophilicity as well as the capillary liquid transport capability. The capillary coefficient increases with the decrease of the microgroove width.  Moreover, the capillary limit may be further increased by fabricating minor microgrooves at the bottom of the major microgrooves with unique layered capillary transport configuration in imitation of sarracenia trichome.