高转速航天柱塞泵滑靴副失效机理及承载界面设计关键技术研究

As a key component of hydraulic servo systems, small-displacement high-speed swash-plate type axial piston pumps are widely used in launch vehicles. To improve the reliability and service life of high-speed aerospace pumps under severe conditions, this project mainly focuses on the failure mechanism and design issue of the slipper pair. First, the variation of the slipper spin speed with the pump speed is investigated for unsteady boundary pressures. Also, the thermal-fluid-structure model coupling model is established to reveal the complex dynamic behavior of the slipper pair and the bearing mechanism of fluid film. Second, a model pump with reduced pistons is developed to realize the multi-position measurements under real operating conditions. Additionally, to explore the slipper failure mechanism experimentally and validate the theoretical model, a novel index plate is proposed to realize continuous measurements of slipper spin speed and other oil film parameters for the slipper pair. Finally, an optimum design method for wear-resistant coating and surface texture on the slipper bearing surface is presented based on the theoretical model and experimental results. It is expected that the surface texture of the slipper can prevent overturning and wear failure under severe conditions through the local dynamic pressure effect and capacity of hard abrasive particle. We hope the above advanced surface treatment technology is helpful to improve the product performance for China Aerospace Science and Technology Corporation and contributes to the technology development of China's rocket engineering.

小排量高转速斜盘式轴向柱塞泵是运载火箭伺服机构核心元件，本项目针对其滑靴副的失效机理和承载界面设计开展应用基础研究，以提高高转速航天泵在恶劣工况下的可靠性和服役寿命。首先，针对航天液压泵高转速的特点，探究滑靴非定常自旋转速及非稳定边界压力随转速变化规律，建立滑靴副固液热多场耦合理论模型，揭示滑靴副的复杂动力学行为和油膜承载特性。其次，研制兼顾多测点分布和拟实性的少柱塞-滑靴组件模型泵，提出实时随动机构和分布盘轴系传动机构，实现滑靴非定常自旋转速和油膜场特性的连续测量，为滑靴副失效机理研究和理论模型完善提供试验支撑。最后，在理论模型和测试装备的基础上，建立滑靴副承载界面的耐磨涂层与表面织构综合优化设计方法，利用表面织构的局部动压效应和容纳硬质磨粒的作用，改善滑靴在恶劣工况下的倾覆和磨损失效，在中国航天科技集团公司产品创新设计中实现工程应用，为我国运载火箭技术发展贡献力量。

机电伺服机构、机电静压伺服机构和容积式伺服机构是运载火箭伺服机构技术发展方向，小排量高转速的液压泵是其核心元件。本项目以小排量高转速斜盘式轴向柱塞泵为研究对象，针对滑靴副在极端服役工况下易倾覆、磨损及气蚀失效的问题，分别在固液热耦合模型、多物理参数测试、承载界面改形改性设计三方面开展基础研究工作，取得了如下进展：.1）在综合考虑滑靴的多自由度复合运动、非稳态边界压力、高速液流惯性力等影响因素，建立非定常边界下滑靴副固液热耦合模型，从理论层面分析在复杂动力学行为下滑靴副的承载特性和失效机理,为高速轴向柱塞泵滑靴副优化设计提供理论支撑。.2）研制高速滑靴副多物理参数拟实测试平台，结合研究对象航天柱塞泵的小排量高转速特点，探索滑靴副油膜承载能力与工况参数及结构参数的映射关系，揭示滑靴副的失效。研究滑靴非定常自旋转速与油膜多物理场参数的拟实测量方法，从而为滑靴副理论仿真模型完善和失效机理探索提供直接的试验数据支撑。.3）建立滑靴副承载界面的改形改性设计方法，研究表面织构内部旋涡对其容纳硬质颗粒效果的影响规律，探索该复合改形改性工艺对提高滑靴在极端贫油工况下服役寿命的实际效果，建立滑靴副承载界面的综合优化设计方法，提高小排量高转速航天柱塞泵在恶劣工况下的可靠性。..本项目发表论文发表学术论文19篇，其中SCI文章10篇，EI论文4篇。其他论文5篇，申请发明专利4项，取得软件著作权1项，培养博士后1名，博士研究生3名，硕士研究生3名。项目负责人获2019年国家优秀青年基金—“高功率密度液压驱动”，指导博士生获得第十届上银优博论文优秀奖。