ISS: Unmasking contact-line mobility for Inertial Spreading using Drop Vibration and Coalescence

PI：Steen，Paul提案编号：1637960拟议的研究重点是研究固定在振动表面上的液滴的行为。该提案是关于发展一种理论来预测液滴振荡模式和液滴的移动，同时进行非常仔细的实验来验证微重力条件下的理论研究结果。在国际空间站（ISS）进行实验的好处是专注于受重力影响的情况。 这项工作的结果可以在地球上的医疗，制造，工业和农业过程中应用。 例如，这些工艺中的一种是浸没式光刻-一种允许在半导体芯片制造工艺中缩小尺寸的重要技术。所提出的工作的结果可以改善惯性扩散过程，这是浸没式光刻的基本组成部分，并将半导体制造中发现的缺陷减少10%。这可能会为半导体行业节省10%的成本，而半导体行业每年的价值已经达到数千亿美元。在地球上规模小、速度快的接触线运动特征在国际空间站上变得更大、更慢，使它们能够在那里进行光学成像。国际空间站的实验是为了研究惯性扩展。惯性扩散对地球上的制造、涂层和成型操作至关重要，但研究起来具有挑战性，受到的关注比粘性扩散少。提出的实验将使接触线迁移率参数进行估计。设想了两种设置。第一个将定期迫使接触线运动的基板附着液滴使用机械振动器，驱动平面正常振荡。使用基于电润湿的触发器，第二设置将引起瞬时液滴-液滴聚结事件，随之产生接触线的大扫掠。迁移率是一个类似于材料的现象学参数，它捕捉了移动接触线的非平衡动力学响应。一旦测量，这个想法是流动性可以用于预测在其他情况下的惯性传播。振动筛和清扫实验分别代表强制和瞬态接触线运动，并将演示的实用程序的流动性参数。对移动的接触线的预测已经接受了有限的测试，因为接触线速度快，具有重要的小规模特征。国际空间站将揭露这些特征，并能够测试惯性传播接触线流动性的高级理论。在某种程度上，该理论与谐振子、薛定谔方程和元素周期表有着相当惊人的相似之处，对广大学生和公众的教育影响将会增加。此外，实验可以用化学元素周期表的比喻来描述为对“运动元素”的探索。拟议的教育计划将通过开发一个外联模块，将在这里进行的研究的主题纳入高中学生，教育女毕业生成为称职的技术领导人。长期影响是通过发展妇女的专业和指导技能，扩大妇女对STEM的参与，并使更多妇女能够在研究生阶段追求更高的职业目标。第二个影响是继续鼓励年轻女孩在高中学习科学和数学，以便她们为在大学选择科学专业做好充分准备和动力。

PI: Steen, PaulProposal Number: 1637960The proposed research is focused on the study of the behavior of drops pinned on a surface that vibrates. The proposal is about developing a theory to predict the drop oscillation modes and the mobilization of the drop, while conducting very careful experiments to verify the theoretical findings at microgravity conditions. The advantage of conducting experiments at the International Space Station (ISS) is to focus on cases that are affected by gravity. Results from this work can have applications on Earth in medical, manufacturing, industrial and agricultural processes. For example, one of these processes is immersion lithography - an important technique that has allowed for down-scaling in semiconductor chip manufacturing processes. Results for the proposed work could improve the process of inertial spreading, a fundamental component in immersion lithography, and reduce defects found on semiconductor manufacturing by 10% over current standards. This can potentially lead to cost savings on the order of 10% in the semiconductor industry, which is already worth several hundred billion dollars annually.Features of contact line motions that are small-scale and fast on Earth become larger and slower on the ISS, making them accessible to optical imaging there. ISS experiments are proposed to study inertial spreading. Inertial spreading is vitally important to manufacturing, coating and forming operations on Earth but challenging to study and has received less attention than viscous spreading. The experiments proposed will enable a contact line mobility parameter to be estimated. Two setups are envisioned. The first will periodically force the contact line motion of a substrate-attached drop using a mechanical shaker that drives plane normal oscillations. Using an electrowetting-based trigger, the second setup will induce a transient droplet-droplet coalescence event with consequent large sweeping by contact lines. Mobility is a material-like phenomenological parameter that captures out-of-equilibrium dynamical responses of a moving contact line. Once measured, the idea is that mobility can be used in predictions of inertial spreading in other situations. Shaker and sweeping experiments represent forced and transient contact line motions, respectively, and will demonstrate the utility of the mobility parameter. Predictions for mobile contact lines have received limited testing because contact line speeds are fast with small scale features of importance. The ISS will unmask these features and enable testing of a high-level theory of mobility of inertially-spreading contact lines. To the extent that the theory has rather striking parallels to the harmonic oscillator, to the Schroedinger equation and to the periodic table, educational impact to a broad group of students and public will accrue. Moreover, experiments can be phrased as a quest for "motion elements" using the metaphor with the periodic table of the chemical elements. The proposed education plan will teach graduate women to be competent technical leaders through the development of an outreach module that integrates the themes of the research conducted here to high school students. The long-term impact is to broaden the participation of women in STEM by developing their professional and mentoring skills, and empowering more women to pursue advanced career goals as postgraduates. A secondary impact is to continue to encourage young girls to pursue science and math in high school so that they are well-prepared and motivated to choose scientific majors in college.