基于LOC的微米级油液颗粒污染物区分检测机理研究

Micron particles in the hydraulic system contain the information of the machine's operation status. It has important significance to the condition monitoring and fault diagnosis of the machine. Qualitative detection and quantitative counting of oil contaminant particles has been the two bottleneck problems in the safely function of the hydraulic system. On the basis of the earlier study, this paper put forward a new method that using the micro-fluidic electromagnetic induction mechanism to accurately measure oil liquid iron and non ferrous metal particle contamination. To use the micro system process for the preparation of size controllable electromagnetic induction micro-fluidic system, we should use the system to measure the abrasive inductance of pulse signal and use the micro inductance analysis system to realize the transformation from inductive signal to particle number and composition. In the theory and numerical simulation, we build micro-channel ferromagnetic wear particle in external magnetic field and internal magnetic field model and micro inductor coil magnetic field model, also build micro coil inductance of the time-harmonic electromagnetic fields and non magnetic abrasive coupling mathematical model, through the combination of the simulation and experimental study, we can obtain the law of how micro inductor electrical parameters and micro-channel geometry parameters impact the sensitivity of the wear particle detection, then we can conclude the general theory about the system detect the abrasive grain qualitatively and quantitatively in the micro-channels. This paper put forward an original mode to distinguish detection and enumeration of fluid particle.

液压系统的微米级颗粒污染物富含设备运行状况的重要信息，对机械设备的状态监测和故障诊断具有重要意义。定性检测和定量计数油液的颗粒污染物已成为液压系统高效安全运行的瓶颈问题。.本课题在前期研究基础上，提出采用微流控电磁感应机理精确测量油液铁质和非铁质金属磨粒污染度的新方法。用微系统加工工艺制备尺寸可控的电磁感应微流控系统，应用该系统对磨粒的电感脉冲信号进行测量，用微感抗分析系统实现电感信号到颗粒数量及成分的精确转换。在理论和数值模拟方面，建立微流道内铁磁性磨粒外部磁化场和内部退磁场模型以及微电感线圈磁场模型，建立微电感线圈的时谐电磁场与非磁性磨粒耦合关系的数学模型，通过仿真和实验研究相结合，阐明微电感线圈电学参数和微流道几何参数影响磨粒检测灵敏度的规律，获得该系统定性、定量地检测微流道内磨粒的一般性理论。本课题为油液颗粒区分检测与计数提供了一种原创的模式。

机械磨损物质含有丰富的摩擦学信息，包括成分、形状、尺寸、数量等，这与设备的磨损部位、磨损类型、磨损过程以及磨损程度息息相关。通过这些不仅可以诊断出系统的故障部位，并且能够对设备进行寿命预测。这对于基于信息融合的现代故障诊断与预报理论来说具有非常重要的价值。定量计数和定性检测能够对油液中的颗粒污染度精确测量。课题研究采用微流控电磁感应机理，在实验室条件下，已经能够对10μm以上铁磁性颗粒以及40μm以上铜质颗粒进行区分检测及计数。并且掌握了微流道内铁磁性磨粒的磁化作用和非铁磁性磨粒的电涡流作用引起线圈等效电感变化的机理；获得了微流道内铁磁性磨粒外部磁化场和内部退磁场模型以及微电感线圈磁场模型，获得微流道内线圈的时谐电磁场与非磁性磨粒耦合关系的数学模型。掌握了微电感线圈电学参数和微流道几何参数影响磨粒检测灵敏度的规律，获得微电感线圈定性、定量地检测微流道内磨粒的一般性理论。本课题研究结果为油液中颗粒污染物定性和定量检测提供了一定的理论基础，不仅具有深远的学术理论价值，还具备广泛的工程应用前景。