图像辅助双转盘电极原子发射光谱油液元素现场检测方法

Oil monitoring is an important means to ensure the safety of major equipment such as aero engines and gas turbines. Element detection is the core content of oil monitoring. Traditional oil element detection methods have been difficult to meet the requirements of high precision, miniaturization and on-site dectection. This project proposes an on-site detection method for oil element based on Image assisted double rotating disc electrode atomic emission spectroscopy. Camera monitoring of arc plasma and echelle-prism cross-dispersive spectrometer structure are utilized to achieve high precision and miniaturization detection of oil elements. The influence of arc plasma state parameters on the measurement results is analyzed. Adopting camera monitoring method, the measurement result compensation model is established with the image principal component analysis and partial least squares algorithm, which improving the measurement accuracy. The influence of electrode structure, turntable speed, etc. on the uniform injection of oil is investigated through experiments. Double-turn electrode structure and arc digital control are utilized for arc stabilization. A spectrometer design method based on echelle grating-prism cross-dispersion is developed. A cylindrical lens is introduced to achieve wide-band astigmatism correction. A high-precision spectral reduction and wavelength calibration algorithm is proposed to achieve miniaturization, wide-band, high-resolution spectral acquisition. Finally an oil element on-site detection system is developed. On-site detection of aero-engine lubricant wear metal element is implemented to test the system performance.

油液监测是保证航空发动机、燃气轮机等重大装备安全运行的重要手段，元素检测是油液监测的核心内容，传统油液元素检测方法已难以满足高精度、小型化、现场检测需求。本项目提出了一种基于图像辅助双转盘电极原子发射光谱的油液元素现场检测方法，采用电弧等离子体摄像监测及中阶梯光栅-棱镜交叉色散结构，实现油液元素高精度、小型化、现场检测。分析电弧等离子体状态参数对测量结果的影响，采用摄像监测法，融合图像主成份分析与偏最小二乘算法，构建测量结果补偿模型，提高测量精度；实验探究电极结构、转盘速度等对油液进样均匀性的影响规律，采用双转盘电极结构、电弧数字化控制，实现电弧稳定；发展基于中阶梯光栅-棱镜交叉色散的光谱探测实现方法，引入柱透镜实现宽波段像散校正，提出高精度谱图还原及波长校准算法，实现小型化、宽波段、高分辨光谱探测；研制油液元素现场检测系统，实现航空发动机润滑油磨损金属元素现场检测，并进行系统性能测试。

油液监测是保证航空发动机、燃气轮机等重大装备安全运行的重要手段，元素检测是油液监测的核心内容，传统油液元素检测方法已难以满足高精度、小型化、现场检测需求。项目提出了一种基于图像辅助双转盘电极原子发射光谱的油液元素现场检测新方法，采用摄像监测法，同时采集电弧图像和发射光谱，利用电弧图像综合反映等离子体状态信息，融合偏最小二乘算法，构建测量结果补偿模型，提高了油液元素现场检测精度，改善了元素检测的重复性；设计了一种双转盘电极原子发射光谱油液元素装置及检测方法，将传统“棒-转盘”电极结构中的棒电极更换为可以旋转的转盘电极，建立了图像辅助双转盘电极油液元素测量模型，通过COMSOL多物理场仿真软件对电弧激发的过程进行了仿真，明确了电极间隙、油膜厚度、外加激励对电弧激发效果的影响规律，根据仿真结果进行了参数优化，根据参数优化结果设计了双转盘电极机械结构和电路；发展了一种全新的基于中阶梯光栅-凹面光栅交叉色散的光谱测量结构，引入柱透镜实现宽波段像散校正；建立交叉色散谱图还原模型，提出了基于最小二乘法和多项式拟合的谱图还原优化算法；研制了油液元素现场检测系统样机，基于偏最小二乘法建立了润滑油金属元素的定量分析模型，提出了一种基于相关系数初遴选(CCPS)的特征波长快速筛选方法，实现了特征波长的快速有效筛选；开展航空发动机润滑油磨损金属元素测量实验，实现了航空发动机润滑油磨损金属元素含量的现场测量。