【作者】 谢伟；

【导师】 周华；

【作者基本信息】 浙江大学 ， 机械电子工程， 2005， 硕士

【摘要】 由于水介质的低粘度、高气化压力和腐蚀性,使得研制纯水液压节流阀面临着解决腐蚀、气蚀破坏以及高压下密封困难等诸多技术难题。因此需要充分考虑水介质特殊的理化性能,从材料、密封形式选择、新型结构设计、加工制造等方面入手,才能研制出性能优良的纯水液压控制阀。气蚀一直是液压阀中经常发生的一个严重问题,随着液压系统向高速、高压及微型化发展,特别是纯水液压方向的迅速发展,气蚀问题显得更为突出。本文研制了两种不同结构的纯水液压节流阀,针对纯水液压阀中的气蚀及其噪声问题,设计和搭建了纯水液压阀气蚀试验系统对不同结构阀口抗气蚀性能进行了研究。论文的主要内容如下: 第一章为绪论。论述了纯水液压的技术现状和研究纯水液压元件面临的关键技术问题,重点分析了关键技术问题之一——气蚀问题的国内外研究现状,提出了减小纯水液压元件气蚀破坏的方法和研究纯水液压阀口气蚀现象的意义。在此基础上,提出了本论文的主要研究内容。 第二章为纯水液压节流阀的研制。从纯水液压节流阀的结构、材料以及密封型式选择等方面进行了研究,解决了纯水液压控制阀中腐蚀、气蚀破坏以及高压下密封等问题,研制了两种DN16纯水液压节流阀。协助设计和搭建了纯水液压控制阀性能试验系统,并在该系统上对所研制的纯水液压节流阀进行了实验研究。实验结果表明所研制的纯水液压节流阀动静态特性良好,满足实用要求。 第三章为纯水液压阀气蚀试验系统的设计和搭建。介绍了纯水液压阀气蚀试验系统的设计思想、气蚀实验装置的设计要求以及实验信号检测与分析,完成了试验系统数据采集硬件的设计和软件的编写。 第四章针对阀口结构对气穴的影响,研究不同结构节流阀口的抗气蚀性能。从流场控制的角度,采用CFD技术对不同结构阀口附近的流场流态进行了仿真,分析了各种边界条件因素对气穴的影响。实验研究不同结构节流阀口的压差—流量特性、阀口临界气穴系数大小,比较分析了不同阀口的抗气蚀性能。实验结果与仿真结果比较吻合。实验结果表明在相同实验条件下,采用分离原则设计的纯水节流阀口较常用的锥形节流阀口刚度大,临界气穴系数小,抗气蚀破坏能力强。 最后对全文做了总结,对今后该课题的进一步开展作了一些展望。更多还原

【Abstract】 Due to low viscidity, high vaporization pressure and erosion of water medium, water hydraulic control valves face technical difficulties such as erosion, cavitation failure and liquid-proof under high pressure. In order to improve the dynamic and static performances of water hydraulic control valves, new operation principles and internal structures of valves must be applied. Along with hydraulic systems developing to high speed, high pressure and micro systems, especially development of water hydraulics, caviation is more and more outstanding. Compared with hydraulic elements, the mechanism of cavitation within water hydraulic elements changes.The technical solutions such as erosion, cavitation and liquid-proof under high pressure in water hydraulic control valves when design water hydraulic valves, are studied in detail in this paper. Two kinds of water hydraulic throttle valves with different internal structures are designed. In order to experimental study cavitation and noise within water hydraulic throttle orifices, water hydraulic valve cavitation testing system is designed and built up. The main contents of this paper are as follows:Chapter 1 presents introduction, which includes technology, development status and technical solutions faced to resolve of water hydraulics. Current technical status of cavitation within water hydraulic elements is analyzed, the solutions to prevent cavitation destroy and the meanings of investigate cavitation within water hydraulic orifices are expatiated. Based on all above, the main contents of this paper are pointed out.Chapter2 introduces the designing and experimental investigation of water hydraulic throttle valve, which includes analysis and calculating of water hydraulic throttle valve, the selection of internal structure and material of valve. Water hydraulic control valve capability testing system is designed and putting up, on which the throttle valves are experimental investigated.Chapter3 introduces the designing and building up of water hydraulic valve cavitation testing system, which includes the designing idea of water hydraulic valve cavitation testing system, designing of valve cavitation testing model and compiling of data acquisition system of water hydraulic valve testing system.Chapter4 suggests the influence on cavitation within different internal structure of water hydraulic orifices. The CFD(Computational Fluid Dynamics) is used to obtain static pressure distribution images near the water hydraulic throttle orifices.更多还原