基于GMM薄膜声音传感器的发动机故障检测

发布时间：2019-04-18 19:27

【摘要】：我国拥有约6500万吨的稀土储量,占世界稀土总储量的23%,是公认的世界第一大稀土资源存储国,稀土行业的快速发展使得我国承担了全世界9成的稀土供应。稀土材料作用广泛,常应用于军工机械、石油化工、玻璃陶瓷、微机电子等现代工程制造领域。作为稀土材料的一个重要分支,超磁致伸缩材料也紧跟整个稀土行业发展而得到的许多知名高校、科研院所的广泛研究以及高科技商业公司的制造应用。超磁致伸缩材料(GMM)具有居里温度高、能量密度大、响应速度快等诸多优点,已被广泛应用于微泵、制动器以及传感器的设计。本文基于维拉里效应,提出一种基于GMM的声音传感器的新结构并针对1.6L电控燃油喷射发动机的应用需求进行结构优化,设计了一款超磁致伸缩薄膜声音传感器,解决了发动机的故障检测方法繁琐、检测步骤冗繁的难题。首先,系统的阐述了超磁致伸缩薄膜声音传感器的性能需求,确定了传感器的工作流程,并基于维拉里效应,对其工作原理进行了理论分析,在理论上验证了基于GMM研制声音传感器的可行性。其次,因超磁致伸缩薄膜声音传感器的工作原理涉及多个物理场,采用COMSOL Multiphysics软件进行多物理场耦合分析,仿真验证了设计的超磁致伸缩薄膜的合理性。仿真过程共分四层:分别是声波信号转换成压力作用于超磁致伸缩薄膜,压力迫使薄膜发生形变,形变使得薄膜内磁畴的磁化强度发生改变,进而,在感应线圈中产生相应的感应电流。根据人耳感知的声音频域范围(20～20000Hz),仿真出超磁致伸缩薄膜在设定的频率范围内的应变曲线。最后,根据1.6L电控燃油喷射发动机结构的参数,设计出一款用于检测发动机故障的超磁致声音薄膜声音传感器。为验证设计的声音传感器可正常工作于发动机的高压和强振的工作环境,采用了有限元法对所设计的声音传感器进行静力学分析、模态分析以及随机振动分析,分析结果显示:所设计的传感器能满足使用条件。
[Abstract]:China has about 65 million tons of rare earth reserves, accounting for 23% of the world's total rare earth reserves, and is recognized as the world's largest rare earth resource storage country. The rapid development of rare earth industry has made China assume 90% of the world's rare earth supply. Rare earth materials are widely used in modern engineering manufacturing fields, such as military machinery, petrochemical industry, glass ceramics, microcomputer electronics and so on. As an important branch of rare earth materials, giant magnetostrictive materials also follow the development of rare earth industry in many well-known universities, research institutes and manufacturing applications of high-tech commercial companies. Giant magnetostrictive material (GMM) has been widely used in the design of micropumps, brakes and sensors because of its high Curie temperature, high energy density and fast response. Based on the Velari effect, a new structure of sound sensor based on GMM is proposed in this paper. According to the application demand of 1.6L electronically controlled fuel injection engine, a giant magnetostrictive thin film sound sensor is designed. The method of engine fault detection is cumbersome and the detection steps are complicated. Firstly, the performance requirements of the giant magnetostrictive thin film sound sensor are systematically described, and the working flow of the sensor is determined. Based on the Velari effect, the working principle of the sensor is analyzed theoretically. The feasibility of developing sound sensor based on GMM is verified theoretically. Secondly, because the working principle of giant magnetostrictive thin film sound sensor involves multiple physical fields, the coupling analysis of multiple physical fields is carried out with COMSOL Multiphysics software, and the rationality of the designed giant magnetostrictive thin film is verified by simulation. The simulation process is divided into four layers: the acoustic signal is converted into a pressure acting on the giant magnetostrictive thin film, the pressure forces the film to deformation, the deformation causes the magnetization of the magnetic domain in the thin film to change, and then the magnetization of the magnetic domain in the film is changed. The corresponding induced current is generated in the induction coil. The strain curves of giant magnetostrictive thin films in the set frequency range are simulated according to the audio frequency domain (20~20000Hz) of human ears. Finally, according to the structural parameters of 1.6L electronically controlled fuel injection engine, a supermagnetically induced sound thin film sound sensor is designed to detect engine faults. In order to verify that the designed sound sensor can work normally in the working environment of high pressure and strong vibration of the engine, the static analysis, modal analysis and random vibration analysis of the designed sound sensor are carried out by using the finite element method. The analysis results show that the designed sensor can meet the operating conditions.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TK407;TP212.9

【相似文献】