面向高寒环境服役的高铁油压减振器低温阻尼特性实验与理论的研究

There is still no knowledge available in the world about the mechanism of damping characteristics of a high-speed rail hydraulic damper becoming distorted and instable when the damper works under extreme cold weather conditions, there is also no theory of low-temperature damping characteristics to support hydraulic damper product design and pertinent vehicle dynamics studies. To tackle the above scientific problems, this project proposal addresses the following research issues: A novel experimental apparatus development for the test of low-temperature pressure-flow characteristics of common hydraulic flow passages and gaps; Experimental and theoretical studies on low-temperature properties of hydraulic oils, on low-temperature fluid mechanics of common hydraulic flow passages and gaps and on low-temperature damping characteristics of a high-speed rail hydraulic damper; Mechanism study on the distorted and instable damping characteristics of a high-speed rail hydraulic damper when it works under extreme cold weather conditions.. The obtained novel experimental apparatus for low-temperature fluid mechanics study and a series of low-temperature theories in this project would directly provide “Core experimental apparatus” and “Basic theory” for the development of high-speed rail facilities capable of being in-service under extreme cold weather conditions, thus, it is of great significance in both scientific research and practicality for the Chinese High-speed Rail Export Strategy.

国际上对高铁油压减振器在高寒服役环境下，其阻尼特性产生畸变和失稳的“机理”不清楚，尚缺乏“低温阻尼特性理论”支持高寒型高铁油压减振器产品的设计和高寒环境下车辆动力学的研究。为了解决上述科学问题，研究常用液压孔口与缝隙出流通道“低温流体力学实验装置”的研制，研究液压油的“低温物理特性”实验与理论，研究常用液压孔口与缝隙出流通道的“低温流体力学”实验与理论，研究高铁油压减振器的“低温阻尼特性”实验与理论，研究在高寒服役环境下，高铁油压减振器阻尼特性产生失稳和畸变的“机理”。项目研究所获得的“低温流体力学实验装置”和一系列“低温理论”，将直接为我国高寒型高铁装备的研制提供“核心实验条件”和补充“基础理论”，这对我国当前的“高铁走出去战略”具有重要的科学研究意义与现实意义。

为了研究高铁油压减振器在低温条件下其阻尼特性产生畸变的机理和低温阻尼特性理论，首先研制了一种适合对各种液压孔口和缝隙进行高低温流体力学实验的新型实验装置，运用该装置针对常用液压阻尼孔进行了在-50℃~+80℃宽温度范围内的流动特性实验，结合对减振器油物理特性的实验与理论研究，获得了液压阻尼孔在宽温度范围内的流量-压力特性和流量系数的理论公式，研究了不同液压油及其温度变化对阻尼孔流量-压力特性曲线、幂指数和流量系数的影响；基于所获得的液压阻尼孔低温流体力学理论模型和实验数据，再结合减振器的低温台架试验结果，揭示了在低温条件下减振器阻尼特性出现畸变的机理，建立了减振器低温阻尼特性的理论模型，并深入研究了减振器低温阻尼特性对车辆动力学系统的影响。项目研究成果为优化包括高铁油压减振器在内的现代液压元件，在宽温度范围内的动态性能提供了新型实验平台和理论基础，这对满足现代高端装备能在极端环境下服役的需求具有重要的科学意义与应用前景。