轴向柱塞泵压力波非线性特征实验研究

Nonlinear Characteristics of Pressure Wave of Axial Piston Pump

为了探讨液压设备中压力波的非线性特征,构建以轴向柱塞泵为动力源的液压实验平台,采集4种油液含气量状况下管道中压力波的时域信号。根据非线性理论和信号处理方法,通过互信息法和Cao方法重构油液压力波信号相空间,利用高斯核函数法和Wolf方法计算压力波信号的关联维数和最大Lyapunov指数。实验结果表明,油液压力信号具有较强的分形特征;随着含气量的增大,油液压力信号表现出较大的随机性和混沌特征。

In order to investigate nonlinear characters of pressure wave in hydraulic devices, the test device is used to the hydraulic system with axial piston pump and the pressure wave signs are gained in time domain at four kinds of air content. Based on nonlinear theory and signal processing, the phase space of pressure wave is reconstructed and the embedding parameters are obtained by the mutual information and Cao＇s methods. The correlation dimensions and the maximum Lyapunov exponent are calculated for nonlinear characteristics using Gauss Kernel Function and Wolf＇s methods, respectively.We can conclude that the pressure wave of the hydraulic oil has strong fractal characteristic and the result shows higher stochastic and chaotic characteristics with increasing the contents of air.