Drop-on-Demand Deposition of Complex Fluids for 3-D Manufacturing

该奖项的研究目的是验证一个假设，即标度定律可以描述复杂流体在超声驱动下产生液滴的物理现象。在这个项目中，超声波液滴生成和沉积的主要应用是开发一种可扩展的增材制造技术，该技术允许从复杂流体中打印三维结构，即具有非牛顿行为或粘度比典型可打印流体高一到两个数量级的流体。感兴趣的材料包括聚氨酯，导电聚合物和陶瓷糊。作为这项工作的结果，声学和液滴形成的物理现象将在多个长度和时间尺度上进行识别。将开发计算流体动力学模型，以捕捉喷射过程的微观细节。这些知识将用于创建新的超声液滴沉积制造技术的设计指南。如果成功，这项研究将使制造技术能够打印各种材料，应用范围从复杂的多材料热塑性部件到光伏电池、燃料喷射器和疫苗输送系统，从而造福社会。克服当前印刷技术的局限性将对增材制造和潜在的喷墨印刷行业产生变革性影响，因为可打印的材料范围将大大扩大。本项目将招募来自代表性不足群体的研究生和本科生。建议的工作将通过开发和维护雾化实验和零件制造设施来加强研究和教育的基础设施。通过加强研究成果的课程、大学生研究机会、积极的行业参与、工程论坛上的论文和演讲，以及一个报告结果和提供已开发的增材制造系统访问的网站，将实现广泛的传播。

The research objective of this award is to test the hypothesis that scaling laws can describe the physical phenomena governing droplet generation from ultrasonic actuation of complex fluids. The primary application of ultrasonic droplet generation and deposition in this project is for the development of a scalable additive manufacturing technology that allows three-dimensional structures to be printed from complex fluids, that is, fluids with non-Newtonian behavior or which have viscosities one to two orders of magnitude higher than that of typical printable fluids. Materials of interest include polyurethanes, conductive polymers, and ceramic pastes. As a result of this proposed work, the acoustics and droplet formation physical phenomena will be identified at multiple length and time scales. Computational fluid dynamics models will be developed that capture microscopic details of the ejection process. This knowledge will be used to create design guidelines for the new ultrasonic droplet deposition manufacturing technology. If successful, this research could benefit society by enabling manufacturing technologies that can print a wide range of materials for applications ranging from complex, multi-material thermoplastic parts to photovoltaics, fuel injectors and vaccine delivery systems. Overcoming the limitations of current printing technologies will have a transformational effect on the additive manufacturing and potentially the ink-jet printing industries, since a much wider range of materials will be printable. Graduate and undergraduate students from under-represented groups will be recruited for this project. The proposed work will enhance the infrastructure for research and education by developing and maintaining facilities for atomization experiments and for part fabrication. Broad dissemination will be achieved through courses enhanced with research results, undergraduate research opportunities, active industry involvement, papers and presentations in engineering forums, and a web-site to report results and provide access to the developed additive manufacturing system.