Abstract: The factors which influence the wave velocity in hydraulic media are analyzed and computed. It is presented that in the high pressure system and oilgas doublephased state the previous assumptions for compressive wave velocity formula in hydraulic media are not true any more. Thus, a new estimation method is necessary. In this paper, a new nonintrusive measurement method is proposed. In this method, the pressure gauges are installed at two different positions on the pipeline to measure the time difference when the compressive wave reaches. Therefore, the wave velocity can be determined. The randomness of elastic modulus under the condition of oilgas doublephased flow is studied in highpressure fluid system. The results provide references for simulation, design and management of hydraulic systems.

Key words: vibration and wave, elastic modulus, velocity of compressive wave, hydraulic media, nonintrusive

摘要： 为了给设计人员与管理人员提供依据，对液压系统介质中压力波波速的影响因素进行理论分析与计算。提出在高压系统中，考虑油—气两相状态下，原有的液压介质中压力波波速决定公式的各项假设条件已不成立，应当重新设定估算方法。采用最新的非插入式测量方法,把压力测量夹具安装在管路的两处，检测压力波达到不同夹具的时间差，计算波速。结果显示压力波波速变化的随机性，该结果可为系统仿真、设备的选型与液压设备管理工作提供参考。

关键词: 振动与波, 体积弹性模量, 压力波波速, 液压介质, 非插入