CAREER: Fundamental Investigation of Thin-Film Evaporation Using Crystalline Porous Inverse Opals

通过相变过程（例如蒸发）耗散极端热量对于从现代电子设备到发电厂冷却的各种应用来说是一个艰巨的挑战。为此，纳米结构由于其大的表面积和将工作流体输送到蒸发表面的能力而引起了极大的兴趣。然而，迄今为止，由于其复杂的结构，确定纳米结构在相变过程中的作用具有挑战性。为了解决这个问题，这个CAREER项目将采用非常规则的多孔介质来研究薄膜蒸发物理。这种多孔介质的结构规则性将允许在材料的形式和蒸发传热之间建立新的关系。该项目的研究成果将纳入教育和外联活动，以促进公众对热传输现象的兴趣，并培训下一代研究人员。综合教育和推广计划将通过新的感官学习教育工具，研究和指导计划，以及一个新的研究生课程纳米相变传热主题。这个CAREER项目的科学目标是利用新型有序多孔介质在与结构相关的蒸发相变物理学中找到新的发现。该项目的具体任务包括：（1）展示具有所需传输特性的亲水性反蛋白石;（2）研究孔隙水平的局部薄膜蒸发（目的是了解这种孔隙的球形凹形状对薄膜蒸发的作用）;（3）检查设备中的传热性能。这些任务可以通过研究蛋白石模板的自组装和金属化来完成，表面工程，多尺度计算模型和高保真测量来验证对蒸发性能的理解。通过多孔介质传输物理学的新发现将为利用新兴多孔材料的下一代热管理设备（如微流体通道、柔性冷却器和热管）的设计迈出一大步。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Dissipating extreme heat through phase change processes (e.g. evaporation) is a daunting challenge for various applications ranging from modern electronic devices to power plant cooling. For this purpose, nanoscale structures have drawn significant interest due to their large surface area and ability to deliver working fluid to evaporating surfaces. However, to date it has been challenging to identify the role of the nanostructures in phase change processes owing to their complex structures. To address this problem, this CAREER project will employ extremely regular porous media to investigate thin-film evaporation physics. The structural regularity of such porous media will allow new relationships to be developed between the form of the material and the evaporation heat transfer. The research outcomes from this project will be integrated into educational and outreach activities to promote public interest in thermal transport phenomena and train the next generation of researchers. The integrated educational and outreach plan will be addressed through new sensory learning educational tools, research and mentoring programs, and a new graduate course on nanoscale phase change heat transfer topics. The scientific objective of this CAREER project is to find new discoveries in structure-related evaporation phase change physics utilizing new classes of well-ordered porous media. The specific tasks of this project include (1) demonstrating hydrophilic inverse opals with desired transport properties; (2) studying local thin-film evaporation at the pore-level (with the aim of understanding the role of the spherical concave shape of such pores on thin-film evaporation); and (3) examining heat transfer performance in the devices. The tasks can be accomplished by studying the self-assembly and metallization of the opal template with surface engineering, multiscale computational models, and high-fidelity measurements to validate understanding of evaporation performance. The new discoveries about the transport physics through porous media will provide a big step forward for the design of next-generation thermal management devices such as microfluidic channels, flexible coolers, and heat pipes that leverage emerging porous materials.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.