基于电容率测量的磁流变液静置沉降特性研究

摘要

为研究磁流变液的静置沉降特性,实现磁流变液沉降特性局部嵌入式实时动态监测,提出了一种基于电容率测量的磁流变液沉降特性测量方法.依据不同固体质量含量的磁流变液电容率的差异,通过检测以磁流变液为介质的圆柱形电容器的电容值,并计算出电容率比率与磁流变液固体质量含量的关系,表征磁流变液沉降特性.设计了磁流变液静置沉降测量装置,并对15个不同固体质量含量的SG-MRF2035 型磁流变液进行了固体质量含量与电容率测量试验.试验结果表明电容率比率与磁流变液固体质量含量呈现正相关特性,基于电容率测量的磁流变液沉降特性测量方法能够有效地用于磁流变液沉降特性测量,并可嵌入到磁流变液应用产品内部实现磁流变液沉降特性的局部、实时动态监测.%In order to identify the static sedimentation characteristic of magneto-rheological fluid (MRF) with local embedded dynamic measurement, a kind of test method of MRF static sedimentation characteristic by capacitivity is proposed.According to the different quality of solid content of MRF having different permittivity, the permittivity ratio can be calculated by testing MRF medium capacitor value of cylindrical capacitor.The measuring equipment of MRF static sedimentation process was designed.The test was took with SG-MRF2035 MRF static, and sedimentation process was lasted 72 h.The results indicate that the local stratification show various precipitate characteristic.The changing trend of capacitivity ratio is identical with the theoretical analysis and intuitive phenomenon of the process of MRF static sedimentation.The stratums were named as clear stratum, restorative stratum, transitive stratum, sedimentary stratum from the top to bottom.The capacitivity ratio increase with the solid quality content decrease.This method of MRF static sedimentation characteristics testing is simple and effective for MRF local embedded dynamic measurement.