无轴轮缘驱动推进器水润滑联合轴承热流固耦合承载机理研究

The water- lubricated bearings with high load carrying is an important part of high-power Shaftless Rim- driven Thruster (RDT). The bearing mechanism of bearings has not yet been clarified under the scientific factors, such as large diameter, viscoelasticity, high pressure, variable condition, wear, disturbance from heat and flow, etc. By taking the water- lubricated bearings of RDT as the research object, a water- lubricated thrust- radial hybrid bearing with characteristics of vulcanized rubber and multilayer materials is designed, and the load carrying principle of the large water- lubricated bearing at the state of starting- up (or low speed) and stable operation based on the thermal- fluid- mechanical coupling is carried out. The mechanical behavior of the water- lubricated bearings under double large deformation and complicated multi-factors is clarified, and the performance optimization method by controlling the deformation is proposed. The separation mechanism of water- lubricated tilting pad interface during speed increment based on tribology and dynamics coupling is revealed, and the accelerated separation method based on external force is proposed. The project is significant for developing theory of fluid-solid-heat coupling and separation property for complex water- lubricated systems, and will provide a theoretical basis and technical support for solving slide bearing problem of RDT for large vessels and transport ships.

高承载能力的水润滑滑动轴承系统是大功率无轴轮缘驱动推进器（Shaftless Rim-driven Thruster，简称RDT）支承问题研究的一项重要内容，在大直径、粘弹性、高比压、变工况、低速磨损以及热和流场环境扰动等严苛因素作用下，其承载机理尚未阐明。本项目以兆瓦级以上RDT水润滑滑动轴承系统为研究对象，研究具有硫化橡胶和多层材料特点的水润滑推-径联合滑动轴承结构方案，开展启动（或低速运行）和稳定工作状态下水润滑轴承热流固耦合承载机理研究，厘清双层大变形和复杂多因素下大直径水润滑联合轴承的力学行为，提出通过控制变形来提升轴承润滑性能的优化方法，揭示启动阶段水润滑可倾瓦承载界面的摩擦学与动力学耦合脱开机制，提出基于外激励力的加速脱开方法。研究成果对于发展复杂水润滑系统热流固耦合与脱开特性分析理论有重要意义，可对解决大型舰艇和运输船舶RDT的滑动支承问题提供理论依据和技术支持。

无轴轮缘驱动推进器（简称RDT）是近年来备受关注的一种船舶新型电力推进器，高承载能力的水润滑轴承是其关键功能保障部件。围绕RDT轴承高比压、变工况和低速磨损等严苛因素下产生的关键科学问题，本项目开展了结构设计、承载机理和关键影响因素研究。设计了5种RDT水润滑轴承创新结构方案，构建了橡胶垫对瓦块的静态支反力与瓦块倾角的关系式，建立了面向稳定工作阶段水润滑橡胶垫弹支可倾瓦推力轴承TEHD模型和面向启动阶段的混合润滑模型，提出了全周水膜压力测试技术和基于荧光的全瓦水膜分布测量技术，开展了弹支可倾瓦轴承均载特性试验、升速过程轴承水膜生成试验和三种轴承变工况200h长时试验，厘清了轴承结构和工况对轴承润滑性能、流态区域特性、均载特性的影响规律，揭示水润滑轴承启动及稳定工作状态下润滑承载机理，通过瓦面和弹性支撑优化提升了轴承承载能力。超额完成了项目预期指标，发表论文12篇（其中SCI论文6篇，EI论文6篇），参加国内外学术会议6次，申请发明专利7项（其中授权5项），培养毕业博士研究生1名、硕士研究生3名，部分成果被应用到海军工程大学、广州海工船舶设备有限公司和泰州三福船舶工程有限公司委托的无轴推进器水润滑轴承研制中。