双联二维活塞式流量计的设计方法与机理研究

The electro-hydraulic proportional/servo control system is widely applied in a great amount of different industries, in which the flow signal plays a critical role. Based on the design concept of "two dimensional hydraulic components" and a review of latest achievements in the area of flow meter and measurement methods of dynamic flow, this project creatively designs a Bi-parallel two-dimensional piston flow meter. A series of research will be carried out consequently. Firstly, a mathematic model of the oil film between the piston and the cylinder is built to study the relationship among lubrication, thickness and internal leakage. Meanwhile, the shear force, the viscous damping force and even the secondary flow has been analyzed to optimize parameters of the architecture of this flow meter. Secondly, moving grid method and fluid-structure coupling is employed to establish a transient model of fluid field on the places which lead to pressure loss, likes the fluid field between the wheels and the cylindrical cams. Thirdly, because the piston has the two-dimensional degrees of freedom, this proposal needs to establish a magnetic model for optimizing the distribution of magnet-Hall elements. Fourthly, the features of dynamic flow signals have been concluded, and three test-rigs will be setup to obtain the static and dynamic characteristics of the flow meter, like accuracy, pressure loss and response time. Moreover, the theoretical result will be analyzed and compared to the test results. The measuring accuracy of this flow meter will be calibrated by a commercial flow meter with higher accuracy for the static flow and a servo-cylinder with displacement sensors for the dynamic flow. As result, this project can achieve a design method for the Bi-parallel two-dimensional piston flow meter and several related fundamental research results, which leads to significant promoting for the development of two-dimensional hydraulic components and the electro-hydraulic proportional/servo controlling technology.

电液比例/伺服技术广泛应用于各行业，其中流量信号是决定系统性能的关键参数。本项目基于二维液压元件设计理念，在国内外研究成果的基础上，提出了一种新型双联二维活塞式流量计并围绕该设计展开系列研究。首先，就二维活塞油膜的润滑、厚度与内泄漏、剪切与粘性阻尼力、二次流与流体阻抗等进行了仿真并优化设计参数；其次，针对计量元件切割流场以及滚轮组件搅动流场等增大压力损失的特征，通过动网格和流固耦合等方式对相应瞬态流场进行了建模并优化结构参数；第三，针对二维活塞的二自由度运动特性，通过建立磁场模型以优化了流量检测磁路的布置；最后，归纳了动态流量信号的特征，通过建立静、动态流量测量实验及测量精度标定台，对流量计的测量精度、压力损失和动态频响等参数进行实验。本项目所得的双联二维活塞式流量计设计方法和机理研究结果对发展二维液压元件提供重大的借鉴，对电液比例/伺服技术的进一步发展具有重要的科学意义和工程应用价值。

电液比例/伺服技术广泛应用于各行业，其中流量信号是决定系统性能的关键参数。本项目基于二维液压元件设计理念提出了一种新型双联二维活塞式流量计并开展了一系列的研究工作。首先，针对双联二维活塞式流量计的设计方法研究，本项目完成了其总体结构设计，并结合就二维活塞油膜的润滑、厚度与内泄漏、剪切与粘性阻尼力、二次流与流体阻抗等问题对关键部件的相关参数进行了优化设计；其次，对于双联二维活塞式流量计的计量特性研究，本项目分析了流量计的压力、流量分布规律，通过建立数学模型的方式对计量单元的静、动力学特性进行仿真优化研究，通过动网格和流固耦合等方式对计量元件切割流场以及滚轮组件搅动流场进行了仿真与实验研究并用以优化结构参数，分析了泄露规律并通过数学模型的方式降低了由内泄露影响的测量误差；最后，针对双联二维活塞式流量计的试验研究，本项目建立了‘搅油’试验台对多种运动部件的搅油损失进行了深入研究，建立了稳态流量标定试验台和标准正弦流量标定试验台，完成了流量计对稳态流量的测量精度及压力损失等工作性能的标定，探索性的完成了流量计对动态流量的测量性能论证。项目完成的双联二维活塞式流量计能够实现稳态流量的高精度测量，所探索的双联活塞式动态流量计原理样机能够实现较好的动态流量信号跟踪，所得的研究双联二维活塞式流量计设计方法和机理研究结果对发展二维液压元件能够提供借鉴，也对电液比例/伺服技术的进一步发展具有重要的科学意义和工程应用价值。