高速重载轴向柱塞泵滑靴副粗糙表面织构热流体润滑与摩擦机理研究

The high speed and heavy load conditions are recognized as the harsh working environment for the slipper pair of axial piston pump. The problem of poor lubricity and serious friction damage of slipper pair have been considered as a bottleneck which restricts the lifetime and reliability of axial piston pump. A new design method of lubrication and antifriction performance based on surface texture optimization is proposed in this project, which focuses on some scientific problems such as enhanced heat transfer, thermo-hydrodynamic lubrication and friction damage on the textured surface of slipper pair under high-speed and heavy load conditions. Some technologies mainly include heat transfer enhancement modeling, thermo-hydrodynamic lubrication modeling, thermo-mechanical coupling contact friction modeling, thermal-fluid-solid-force multi-field coupling solution and multi-objective optimization design in this study. The technologies are emphasized to establish structure-function integration design of slipper pair and clarify optimum design principle of surface texture of slipper pair with low friction, high heat dissipation and high bearing capacity. The test equipment associated with the prototype model will be set up and the testing results will be provided to verify the relevant theoretical results and optimization results. The lubrication and friction characteristics of the textured surface interface of the slipper pair can be mastered by a comprehensive evaluation of its friction resistance, which can be used to clarify the mapping rule between the mapping rules among the surface texture of the slipper pair, the heat dissipation, fluid resistance reduction, the lubrication bearing capacity and the friction damage performance. This study will provide a basic theory for the design of the reliability and life of the axial piston pump under complex operating conditions, and provide the key technical support for the development of the core components of the high-speed and heavy-load axial piston pump.

高速重载工况对轴向柱塞泵的滑靴副提出了严峻挑战，局部润滑的快速劣化和摩擦损伤失效问题已成为制约轴向柱塞泵使用寿命和可靠性的瓶颈。本项目提出一种基于滑靴副粗糙表面织构优化的热流体润滑减摩性能设计方法，重点研究高速重载条件下滑靴副表面织构界面强化传热、热流体润滑及摩擦损伤等科学问题，突破表面织构的流体强化传热建模、热流体动力润滑建模、热机耦合接触摩擦建模、流-固-热-力多场耦合求解、多目标优化设计等关键技术，实现对滑靴副的结构、功能一体化设计，阐明低摩擦、高散热、高承载性能滑靴副的表面织构优化设计原理。研发相关实验装置，通过实验研究对相关理论成果进行验证，并揭示滑靴副表面织构界面润滑与摩擦特性，对其抗摩擦性能做出综合评价，探明滑靴副表面织构与其散热减阻、润滑承载能力及摩擦损伤性能之间的映射关系。本研究将为复杂工况下滑靴副的设计与优化提供应用基础理论，为我国核心基础元器件研制提供技术支撑。

滑靴副是轴向柱塞泵的关键摩擦副，频繁承受周期性压力冲击，极易产生润滑失效，甚至严重磨损，影响柱塞泵的使用寿命。针对高速重载轴向柱塞泵滑靴副间隙密封界面传热低、热流体润滑条件差及摩擦损伤严重等问题，本项目从表面织构强化传热、流体润滑承载性能和热机耦合接触三个方面进行深入分析，项目主要研究成果包括：（1）研究了织构化滑靴副内部非定常流动及其强化传热机理，建立了非定常k-ε湍流数值计算模型，揭示了表面织构设计对柱塞泵摩擦部件强化传热与流动减阻现象的产生机理与原因，发现半球形表面织构在低速区产生马蹄形旋涡现象，有利于增强表面织构阵列中凹坑脊两侧的传热效果。（2）研究了滑靴副粗糙表面织构流体动力润滑行为，建立了织构化滑靴副弹性流体动力学模型，得到了表面粗糙度参数、几何结构参数和润滑承载性能之间的映射关系，从理论和实验的两个方面，提出了基于序列二次规划算法和遗传算法的混合进化优化方法和基于自适应代理模型的织构化滑靴副多目标优化方法，得到了摩擦部件的表面织构优化设计准则，并研制了织构化摩擦副热力学特性测试装置，用于验证柱塞泵织构化摩擦副的强化传热与润滑性能。（3）建立了温度－应力实时耦合的织构化滑靴副弹塑性接触模型，阐释了接触副预滑移阶段的静摩擦行为和完全滑动阶段的摩擦热－应力耦合现象的机理和产生条件，发现滑移速度越大，摩擦温度越高，材料的承载能力下降越显著，接触副的摩擦阻力下降越多，摩擦系数减小。(4)研究了织构化滑靴副配对材料的摩擦学性能，提出了等离子喷涂MoS2表面强化技术在材料表面形成耐磨涂层的方法，提升轴向柱塞泵摩擦部件的耐磨性能。研究表明在摩擦热和应力的作用下材料接触表面发生摩擦化学反应，接触表面形成Cu2S和FeS润滑转移膜，降低摩擦系数和磨损率。本课题的研究成果不仅对轴向柱塞泵摩擦副润滑减摩控制与优化设计提供新的思路，而且为我国高端液压基础元件的研制提供理论和技术支撑，具有重要研究意义和应用价值。