航空柱塞泵仿生柱塞副微观界面润滑机理研究OA

In modern aviation hydraulic systems,piston pumps are critical components whose operational efficiency and longevity are heavily dependent on the lubrication performance at the micro-interface of plunger pairs.Under extreme conditions of high pressure,high speed,and variable temperatures,the lubrication state remains inadequately characterized,and the potential of bio-inspired surface engineering has not been thoroughly explored.The work aims to systematically investigate the effect of biomimetic micro-textures on the interfacial lubrication behavior of plunger pair in aviation piston pump,with the goal of providing both theoretical insights and practical solutions for enhancing tribological performance under demanding operational environments.The surface morphology of the tiger-spotted clam was meticulously characterized with high-resolution laser confocal microscopy.Based on this biological template,two biomimetic micro-texture geometries of semi-elliptical and rectangular shapes,were designed.Three-dimensional computational fluid dynamics simulations were employed to analyze the pressure distribution,velocity streamline distribution,load-carrying capacity,and variation law of friction coefficient within the micro-textures.An extensive parametric study was conducted to evaluate the effects of several key parameters on lubrication performance.The micro-texture depth varied from 0.15 mm to 0.30 mm in increments of 0.05 mm.The wall sliding speed was tested over a range of 1 m/s to 6 m/s,while the inlet oil supply distance was examined from 0.01 mm to 0.06 mm.Additionally,the inter-texture spacing was investigated across values ranging from 0.25 mm to 0.40 mm.The transient evolution of the lubricating film and its interaction with the textured surface were closely examined to elucidate the dynamic mechanisms governing micro-interfacial lubrication.It is indicated that under varying microstructure depths,wall movement velocities,inlet distances,and collaborative arrangements of microstructure arrays,the two types of microstructures exhibit similar pressure distributions.However,in terms of velocity streamlines,the semi-elliptical microstructure demonstrates smoother flow patterns,whereas the rectangular microstructure tends to induce flow separation at its sharp corners.In terms of load-bearing capacity,the semi-elliptical microstructure consistently outperforms the rectangular structure.The optimal bearing capacity is achieved at a depth of 0.30 mm,a wall movement velocity of 6 m/s,an inlet distance of 0.06 mm,and a spacing of 0.30 mm.Regarding frictional performance,the behavior of the two microstructures varies depending on dimensions and operating conditions.When the depth exceeds 0.25 mm and the wall velocity is below 4 m/s,the semi-elliptical structure exhibits superior friction characteristics.Conversely,when the depth is less than 0.25 mm and the velocity exceeds 4 m/s,the rectangular microstructure demonstrates a lower friction coefficient.Under varying inlet distances,the rectangular microstructure maintains relatively better performance,while under collaborative array conditions,the semi-elliptical microstructure exhibits more significant friction-reducing effects.The lubrication characteristics of the microscopic interface in the piston pair are collectively affected by the micro-hydrodynamic effect,the wall velocity-dominated micro-inertia effect,the inlet entrainment effect induced by varying inlet distances,and the synergistic effect of microstructure arrays.Compared with rectangular microstructures,semi-elliptical microstructures demonstrate superior overall lubrication performance.The findings of this work can provide a theoretical foundation for the design of biomimetic microstructures in aviation piston pairs and the optimization of their interfacial lubrication properties.