水中容腔式压力传感器频响特性的非线性气泡效应分析

摘要

According to the measurement results of the frequency response characteristic test, and the theory of laminar flow assumption and the modeling methods for linear model, nonlinear bubble effect analysis model applying to measurement on wide-range changing of pulse pressure was derived in adiabatic conditions. Further more, the calculated results based on this model were consistent with the measurement results. Comparing different simplified models with each other,it was proved that the main factors, which affected the accuracy of the analysis model about the sensor frequency response characteristics, were the nonlinear effect of gas rigidity, followed by the factors as the quadratic component of pressure derivative and the length of liquid column. The specific stiffness of sensor determined the range of frequency response measurement of the liquid pulse pressure, but there was no linear correlation between them. According to the test results, the viscosity coefficient and the chamber volume of the bubble effect model should be modified, to take the siltation and surface tension effects of liquid into account, meanwhile to reflect the turbulence effect and heterogeneity of flow field in the parameters. Without regard to the film effect of sensor,the nonlinear bubble effect model can be used to analyze dynamic pressure response for gas.%　　根据频响特性试验的状态和测量结果，借用线性模型的层流假设和建模方法，在绝热条件下推导大范围变化压力的非线性气泡效应分析模型，获得与测量曲线一致的计算结果。通过对不同简化条件模型的计算比较，证明影响传感器频响特性分析模型精度的主要因素是气体刚度的非线性效应，压力导数平方项是次要影响因素，液柱长度变化的影响较小。传感器的比刚度决定了液体脉冲压力测量的频响范围，两者不存在线性相关性。气泡效应模型的粘性系数和容腔体积需要根据试验结果进行修正，以计及液体的淤积和表面张力效应，并将流场的紊流效应和不均匀性体现在参数变化中。本模型在不计膜片影响时可用于气体动态压力响应分析。