GOALI: Development of Next Generation Microcombustor-Thruster Using Anisotropic Nano-Coating

微型燃烧室是微型动力系统中的关键部件，用于小型和便携式发电，以及用于微型推进器、推力矢量控制、小型飞行器和小型卫星。微型燃烧室的一大挑战是实现稳定燃烧和最大限度地减少热损失。为了应对这一挑战，该项目计划开发具有高度各向异性导热系数的热障涂层，以最大限度地减少热损失，并增强微型燃烧器中的火焰稳定性。高性能微型燃烧室的发展预计也将极大地惠及工业部门的许多领域，包括推力矢量控制、燃气轮机发动机、火箭发动机、柴油发动机和便携式电源，因为它们都面临着类似的挑战。该项目包括马里兰大学著名的宝石项目的多年本科生研究部分。让这些本科生和研究生参与这个项目，将有助于提高他们对科学和技术的兴趣，为这些学生提供获得实践研究经验的研究培训机会。基于网络的教育和国际教育也将进一步扩大拟议研究和教育活动的国际影响。该项目将探索在亚毫米级微型燃烧器内壁上开发和沉积具有高度各向异性导热系数的新颖和创新的纳米结构热障涂层的方法。这种类型的热障涂层能够增强沿燃烧室表面的热再循环，同时将通过其表面的热损失降至最低，从而提高火焰稳定性。该方法将扩大火焰稳定极限，提高微型燃烧室的燃烧效率和热性能。在微型燃烧室中，高效的热管理以及废气和新鲜反应物混合物之间的高效热交换是至关重要的。在所提出的多层热障涂层中，由于纳米片之间的界面电阻低于1W/mK，跨平面方向的热导率将显著降低。此外，这些热障涂层将具有高抗氧化性、耐腐蚀性和抗腐蚀性。该项目将影响用于地面和空间应用的下一代微型燃烧器和推进装置的发展。

Micro-combustors are critical components in micro-power systems for small and portable power generation as well as for use in micro-thrusters, thrust vector control, small aerial vehicles and small satellites. One of the big challenges in micro-combustors is to achieve stable combustion and minimize the thermal losses. Aiming to address this challenge, this project plans to develop thermal barrier coatings with a highly-anisotropic thermal conductivity to minimize the heat loss and enhance flame stability in micro-combustors. Development of high-performance micro-combustors is also expected to greatly benefit many areas of industrial sectors, including thrust vector control, gas turbine engines, rocket engines, diesel engine, and portable power sources, since they all have similar challenges. This project include a multi-year undergraduate research component for the University of Maryland's prestigious Gemstone Program. Involving these undergraduate and graduate students in this project will help enhance their interests in science and technology by offering these students research training opportunities to gain hands-on research experiences. Web-based education and international education will also further broaden the international impacts of the proposed research and educational activities.This project will explore means to develop and deposit a novel and innovative nanostructured thermal barrier coating with a highly anisotropic thermal conductivity on the inside walls of sub-millimeter-scale micro-combustor. This type of thermal barrier coating is able to enhance heat recirculation along the combustor surface while minimizing the heat loss through its surface, therefore promoting flame stability. The proposed approach will expand the flame stability limits and enhance the combustion efficiency and thermal performance in micro-combustors. Efficient thermal management with efficient heat exchange between the exhaust gases and fresh reactant mixture is critical in the micro-combustors. In the proposed multilayer thermal barrier coating, the thermal conductivity in the cross-plane direction will be significantly reduced by interfacial resistance between the nanosheets to values below 1 W/mK. Additionally, these thermal barrier coatings will have high resistance to oxidation corrosion and decomposition. This project will influence the development of the next-generation of miniature scale combustors and propulsion devices for use in terrestrial and space applications.