大流量电液换向阀动态特性仿真及流场分析

发布时间：2018-01-03 06:40

本文关键词：大流量电液换向阀动态特性仿真及流场分析　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着采煤技术向高产高效方向发展，液压支架的“速度”性能对综采工作面效率的影响越来越显著。目前常用的性能良好的大流量电液换向阀的额定流量为400L/min，不能满足支架进一步提升承受阻力，增大移动速度的要求。因此，需要增大电液换向阀的额定流量，对电液换向阀进行大流量的研发愈发重要。本文对某常用的进口电液换向阀结构特点和工作原理进行分析，对其关键零部件受力分析，进而推导出电液换向阀的数学模型，在此基础上对主阀进行设计计算，设计了一款大流量电液换向阀。首先运用Matlab软件对新设计的大流量电液换向阀模型进行仿真，得到其初始参数下的动态特性，，然后利用系统建模动态仿真软件AMESim对电液换向阀系统进行动态特性分析，最后运用流体动力学分析软件Fluent对电液换向阀进行流场仿真。在AMESim平台上，建立了换向阀电液控制系统，分析阀芯位移、阀芯速度、出口压力与出口流量等特性。研究结果表明：主阀芯在0.14s开始运动，0.23s可实现阀口稳定开启，阀芯运动平稳，阀芯出口流量达到稳定值时为1013L/min。另外，研究了阀芯行程、阀芯锥角角度、主阀节流孔直径和弹簧力等关键参数对换向阀阀芯位移、阀芯速度、出口流量与压力的影响，选取了合理的参数值。利用CFD计算流体力学软件Fluent对大流量电液换向阀内部流场进行仿真分析，得到了流场的静压力分布云图、速度分布云图、速度矢量图和湍动能分布云图等特性曲线。通过对进油工况P-A及回油工况A-T两种情况的仿真结果的分析得到，大流量电液换向阀内部压降分布均匀，没有明显的漩涡区。在此基础上，本文进一步讨论了在不同开口度、不同进液阀套孔锥角和不同环形腔直径的情况下，主阀内部流场的特性，结果表明：随着开口度的增大，最大速度区域面积增大，漩涡区面积和强度减小，这样加快了主阀的开启时间，有利于提高液压支架的工作速度，也有利于减轻阀芯的磨损和冲击。通过对大流量电液换向阀不同进液阀套孔锥角进行仿真分析，验证了斜孔出流有利于减小漩涡强度，对锥角角度的选取提供了理论依据。此外，当环形腔外径增大时，湍动能的损失减小，主阀进出口的压力损失减小，能够有效提高阀的通流能力。
[Abstract]:With the development of coal mining technology to the high yield and high efficiency, hydraulic support "speed" on the performance of fully mechanized working face efficiency effect is more significant. The rated flow of currently used good performance of high flow electro hydraulic valve for 400L/min, support to further enhance the bearing resistance cannot meet the requirements, increasing movement speed. Therefore, the need for additional the flow increases the electro-hydraulic valve, the development of large flow of electro-hydraulic reversing valve is more and more important.
This paper analyzes some commonly used imported electro-hydraulic valve structure characteristic and work principle of force analysis of the key parts, then deduces the mathematical model of the electro-hydraulic valve, the main valve on the basis of the design, design of a large flow of electro-hydraulic valve. The first is simulated with Matlab software the new design flow of the electro-hydraulic valve model, the dynamic features of the initial parameters, and then use the system modeling and dynamic simulation software AMESim to study the dynamic characteristic of the electro-hydraulic valve system, finally using fluid dynamics analysis software Fluent numerical simulation of the electro-hydraulic valve.
On the platform of AMESim, a valve electro-hydraulic control system, valve spool displacement, velocity analysis, outlet pressure and outlet flow characteristics. The results show that: the main valve to start the movement in 0.14s and 0.23s can realize stable valve opening, valve movement smoothly, valve outlet flow reaches a stable value for 1013L/min. in research the spool stroke, the valve cone angle, the key parameters of the main valve orifice diameter and spring force the valve spool displacement, spool speed, influence the export flow and pressure, choosing proper parameter values.
The computational fluid dynamics software Fluent to simulate the flow of the electro-hydraulic valve internal flow field by using CFD, the static pressure distribution of flow field, velocity distribution, velocity vector and turbulent kinetic energy distribution characteristic curve. Through the analysis of simulation results of inlet conditions of P-A and oil return conditions A-T two cases the flow of the electro-hydraulic valve internal pressure distribution, no obvious vortex zone. On this basis, the paper further discusses the opening in different, different liquid inlet valve sleeve hole cone angle and different annular cavity under the condition that the diameter of the main valve internal flow characteristics, the results show that with the increase of opening the maximum speed of the area increases, reducing the area and intensity of vortex, thus speeding up the opening time of the main valve, is conducive to the improvement of the hydraulic support working speed, but also help to reduce the abrasion and impact on the spool. Simulation analysis of high flow electro hydraulic valve with different inlet valve sleeve hole cone angle, verify the inclined hole flow to reduce the vortex intensity, provides a theoretical basis for the selection of cone angle. In addition, with the increase of cavity diameter, turbulent kinetic energy loss is reduced, the pressure loss of the main valve import and export decreases, can effectively improve the valve flow capacity.

【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD355.4;TH137.52

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