Research Initiation Award: Theoretical and Computational Methods for Robust Retrieval of Effective Electromagnetic Properties of Random Composite Materials

研究启动奖为历史上黑人学院和大学的初级和中级职业教师提供支持，他们正在建立新的研究项目或重新定向和重建现有的研究项目。预计该奖项将有助于进一步提高教师的研究能力和效率，改善家庭机构的研究和教学，并使本科生参与研究经验。 霍华德大学的奖项支持旨在优化具有电磁（EM）能力的随机复合材料工程的研究。 这样的能力包括EM干扰屏蔽和EM可观测性增强，和/或EM感测能力。这在商业和国防技术中开辟了广泛的应用，例如电气/电子设备，通信系统，石油和天然气工业以及军事和执法。复合材料的宏观性能取决于各组分的几何形状、分布、体积分数和性能。虽然周期性分布的复合材料的有效电磁特性的数值提取技术是相对完善的，简单的实施，那些随机分布的复合材料还没有得到充分的探讨。本研究的目的是发展一个严格的理论和准确，有效的数值方法，以提供随机复合材料的有效电磁性能的静态和动态的情况下的尺度相关的界限。所提出的EM均匀化理论将被纳入一个全频率稳定的配方，这将是解决蒙特-卡罗模拟使用有限元和区域分解方法的建设。一个随机模拟方法也将被开发来表征材料的随机性和几何不确定性，并实现在EM属性检索的效率提高。所提出的理论和方法将导致国家的最先进的均匀化工具的随机复合材料的表征和分析的发展。这反过来又将使新的设计方法在随机复合材料的理论指导和计算支持的基础上。该项目包括一个广泛的教育和推广活动，包括学生参与历史上在这一领域的研究，并开发视频剪辑和演示，以传播的结果给公众。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Research Initiation Awards provide support for junior and mid-career faculty at Historically Black Colleges and Universities who are building new research programs or redirecting and rebuilding existing research programs. It is expected that the award helps to further the faculty member's research capability and effectiveness, improves research and teaching at the home institution, and involves undergraduate students in research experiences. Howard University’s award supports research that seeks to optimize the engineering of random composite materials that have electromagnetic (EM) capabilities. Such capabilities include EM interference shielding and EM observability enhancing, and/or EM sensing capabilities. This opens a wide range of applications in commercial and defense technologies, such as electrical/electronic devices, communication systems, oil and gas industries, and military and law enforcement. The macroscopic properties of composite materials depend on the geometry, distribution, volume fraction, and property of each constituent. While the numerical extraction techniques for the effective EM properties of periodically distributed composite materials are relatively well established and straightforward to implement, those for the randomly distributed composite materials have not been fully explored. The objective of this proposed research is to develop a rigorous theory and accurate and efficient numerical methods to provide the scale-dependent bounds of the effective EM properties of random composites in both static and dynamic cases. The proposed EM homogenization theory will be incorporated in the construction of an all-frequency stable formulation, which will be solved in Monte-Carlo simulations using finite element and domain decomposition methods. A stochastic simulation method will also be developed to characterize the material randomness and geometrical uncertainty and achieve an improved efficiency in the EM property retrieval. The proposed theories and methods will lead to the development of state-of-the-art homogenization tools for the characterization and analysis of random composite materials. This in turn would enable new design methodologies in random composites based on the theoretical guidance and computational support. The project includes an extensive education and outreach activities, including the involvement of students historically underrepresented in this field of research, and the development of video clips and demonstrations to disseminate the results to the public.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.