基于分形特征的挖掘机多路阀配合面粗糙微结构的泄漏机理研究

项目名称： 基于分形特征的挖掘机多路阀配合面粗糙微结构的泄漏机理研究

项目编号： No.51505211

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 机械、仪表工业

项目作者： 贾文华

作者单位： 南京工程学院

项目金额： 20万元

中文摘要： 针对当前液压挖掘机多路阀普遍存在的泄漏现象，以阀芯阀腔配合面间隙流动特性为突破口，研究泄漏产生的机理，从而减少甚至消除泄漏。本项目拟从多路阀阀芯阀腔配合间隙粗糙微结构表面微观轮廓着手，结合W-M函数和Monte Carlo方法建立配合面粗糙微结构的表面形貌模型；采用参变量变分原理和相应的有限元参数二次规划方法，通过改进的微尺度流动Micro-PIV测量技术，获得滑移边界条件；研究间隙内油膜的流动特性和传热特性，建立阀芯阀腔配合间隙泄漏模型，提出配合面粗糙微结构的优化方法，寻求配合面粗糙微结构表面形貌与多路阀泄漏、磨损之间的关联性，并通过实验对结果进行验证。多路阀是液压挖掘机液压系统中的核心部件，其设计制造水平直接影响液压挖掘机的整机性能。本项目的研究成果为保证应用于挖掘机上的多路阀执行其合流、再生、优先、流量控制等复杂功能的稳定性和可靠性，形成我国自主的高性能多路阀设计方法奠定理论基础。

中文关键词： 粗糙微结构；分形；边界滑移

英文摘要： In view of the internal leakage issue which exists prevalently in the multi-way valve, the flow characteristics in microchannel and heattransfer propertics are seen as the breakthrough to study the production mechanism of internal leakage in aim to reduce or even eliminate internal leakage. The project proceeds from the matching surface microcosmic appearance between the spool and valve bush, introduces fractal theory and creates precise 3d model of matching surface .Through improved micro-scale flow Micro-PIV measurement techniques, the molecular dynamics simulation and CFD and calculate the slip boundary condition are combined. The flow characteristics and heattransfer propertics of oil film between the clearance are researched, the model of internal leakage is creased, the optimization method of matching clearance structure is put forward. At last, a complete method of research about micro-scale flow between the spool and valve bush is formed. In addition, the results are tested and revised through experiments. Multi-way valve is the kernel component of hydraulic system in hydraulic excavator whose level of design and manufacture could directly affect the performance of hydraulic excavator. This project has practical significance for the internal leakage issue. Furthermore, it lays the theoretical foundation for the independent design of the high-performance hydraulic excavator in our country and promotes the development of our Micro-scale flow field.

英文关键词： Slightly Rough; Surface Fractal ;Boudary Slip