Analysis of multiphase flows for functional coatings

功能涂层的多相流分析

• 批准号: RGPIN-2020-06773
• 负责人: Dolatabadi, Ali
• 金额: $ 4.08万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741422
• 关键词: Analysis; multiphase; flows; functional; coatings

This proposed research program on multiphase flows has been motivated primarily by the substantial and growing interest in applying the emerging suspension thermal spray process to produce so-called "functional" coatings. Conventional thermal spray processes such as plasma and high velocity oxygen fuel (HVOF) are already used extensively in the aerospace, automotive, and power generation industries to apply protective coatings on engine, landing gear, and turbine components that are exposed to heat, corrosion, erosion, and wear. They use particle diameters of tens of microns that are fed into the spray gun and heated and accelerated to high velocities. Recently, substantial research efforts have been applied to emerging suspension thermal spray (STS) systems that deposit much smaller nanoparticles and create coatings with superior performance. In STS, a liquid suspension of dispersed nanoparticles is injected into thermal spray flames, which atomize the suspension droplets. The liquid droplets then evaporate allowing the nanoparticles contained in the droplets to accelerate and melt as in a conventional thermal spray process. This technology shows significant promise to create coatings with feed rates suitable for many industrial applications. For example, the nano-structured coatings deposited by the suspension spraying technique demonstrate remarkable wear resistance, enhanced catalytic behaviour and superior thermal insulation. In STS, coating quality and functionality depend primarily on the suspension penetration into the jet, the primary and secondary atomization of the suspension, and the slurry droplet evaporation. Characterizing the multiphase flow and heat transfer associated with the suspension atomization in an all speed (subsonic to supersonic) flow is a challenging research topic requiring numerical and experimental studies. The proposed research program addresses both these aspects by studying multiscale multiphase spray process flows and the resultant functional coatings. We will explore the development of environmentally friendly durable omniphobic coatings, specifically, superhydrophobic, icephobic, and slippery liquid-infused porous surfaces. The computer codes that we generate to simulate the atomization process in industrial sprays also have broad applications in the design of nozzles for metal powder manufacturing, engine fuel systems, agricultural sprayers, dryers, and inhaled drug delivery systems. We anticipate that the results of this study will facilitate the manufacture of key aerospace components, and have a great impact on the Quebec aerospace industry. The technology will also find many applications in the automotive, power generation, and biomedical industries, all of which are important to the Canadian economy.

这项拟议的多相流研究计划主要是由于人们对应用新兴的悬浮热喷涂工艺来生产所谓的“功能”涂层的巨大兴趣和日益增长的兴趣所推动的。等离子和高速氧燃料 (HVOF) 等传统热喷涂工艺已广泛应用于航空航天、汽车和发电行业，在暴露于热、腐蚀、侵蚀和磨损。他们使用直径为数十微米的颗粒，将其送入喷枪并加热并加速至高速。最近，大量研究工作已应用于新兴的悬浮热喷涂（STS）系统，该系统可以沉积更小的纳米颗粒并形成性能优越的涂层。在 STS 中，分散纳米粒子的液体悬浮液被注入热喷涂火焰中，使悬浮液液滴雾化。然后，液滴蒸发，使得液滴中包含的纳米颗粒加速并熔化，就像传统的热喷涂过程一样。该技术显示出创造出适合许多工业应用的进料速率的涂层的巨大前景。例如，通过悬浮喷涂技术沉积的纳米结构涂层表现出显着的耐磨性、增强的催化性能和优异的隔热性。在 STS 中，涂层质量和功能主要取决于悬浮液渗透到喷射中、悬浮液的初级和次级雾化以及浆料液滴蒸发。表征全速（亚音速到超音速）流中与悬浮液雾化相关的多相流和传热是一个具有挑战性的研究课题，需要数值和实验研究。拟议的研究计划通过研究多尺度多相喷涂工艺流程和由此产生的功能涂层来解决这两个方面。我们将探索开发环保耐用的全疏涂层，特别是超疏水、疏冰和光滑的液体注入多孔表面。我们生成的用于模拟工业喷雾雾化过程的计算机代码在金属粉末制造喷嘴、发动机燃料系统、农用喷雾器、干燥器和吸入药物输送系统的设计中也有广泛的应用。我们预计这项研究结果将促进关键航空航天部件的制造，并对魁北克航空航天业产生重大影响。该技术还将在汽车、发电和生物医学行业得到广泛应用，所有这些行业对加拿大经济都很重要。