基于故障树分析法的航空活塞发动机故障诊断专家系统研究

【作者】 严军；

【导师】 李辉； 付尧明；

【作者基本信息】 电子科技大学 ， 软件工程， 2010， 硕士

【摘要】 航空活塞发动机的故障问题不但直接威胁发动机的安全高效运行,而且还可能诱发其他故障,甚至发生飞行事故。因此,准确诊断和迅速排除故障对于发动机的安全运行意义重大。本文在对航空活塞发动机的组成结构及功能原理作全面分析的基础上,把发动机分为7个子系统,即发动机本体、点火系统、燃油系统、滑油系统、进气系统、排气系统、操作系统。通过对各个系统的失效模式和故障原因的全面分析,建立相应的故障树,从而直观的表现出各个系统出现故障的原因以及故障模式。由于维修人员的维修经验及水平不可能全都处于专家级,随着经验丰富的老一辈维修人员的退休或专家级维修工程师的人事变动,对于一个维修单位来说,很有可能就会出现一个维修水平的断档问题。那么怎样才能避免这种情况的发生,并有效的延续现有的维修能力,有计划,有步骤的提高单位的维修水平及质量呢?我们在本文中将通过把维修人员的丰富的排故经验和维修工程师的知识,系统的组织起来,然后进行汇总和提炼,再转化成为计算机能够识别地代码存储于计算机内部,也就是产生诊断知识库,建立一套发动机故障排除专家系统,再通过人机界面与用户交流的方式引导用户逐步进行深入诊断,最终确定发动机的故障部位和原因,给出诊断结论,并提出维修建议,实现发动机故障的专家级诊断。这样不仅避免了因维修单位人事变动影响单位的维修水平,而且便于让一般的维护人员在遇到故障后,也能够通过专家系统的提示,逐步找出故障原因,并最终排除故障。具体来说就是将航空活塞发动机的大量故障数据和维修经验以故障树的形式表示出来,同时对故障树进行汇总和提炼,生成航空活塞发动机专家系统,最终确定航空活塞发动机故障的部位和原因,提出维修建议并最终实现发动机故障的完全排除。更多还原

【Abstract】 Aviation piston engine failure issue is not only a direct threat to the safe and efficient engine operation, but may also induce other failure, or even flying accidents. Therefore, accurate diagnosis and prompt troubleshooting for the safe operation of the engine is significant.The thesis makes a comprehensive analysis of aviation piston engine structure and function of the composition principle and divides the engine into seven sub-system, namely, the engine body, ignition system, fuel system, oil system, air intake system, exhaust system, the operating system. By a comprehensive analysis of each system failure mode and cause of failure and establishing the corresponding fault tree, they can show the various systems and intuitive failure causes and failure modes.Due to the experience and level of maintenance personnel can not be all at the expert level, when the older generation of experienced maintenance personnel retired and maintenance engineer or an expert-level personnel changes, for a maintenance department, most likely there will be a maintenance level of merchandise in question. So how can we prevent this from happening, and effectively a continuation of the existing maintenance capacity in a planned, to improve the level step by step and quality of the maintenance unit does? In this article, we will be rich by the maintenance staff, so the row of experience and knowledge of maintenance engineers, the system organized and then summarized and refined, and then translated into a computer to recognize in the code which is stored on a computer inside, that is, the knowledge generated Diagnosis library, the establishment of an engine troubleshooting expert system, and through man-machine interface, the way they interact with the user guide users step by step in-depth diagnosis and ultimately to determine the location and cause the engine to fail given diagnostic conclusions,and make maintenance recommendations to achieve the engine failure of the expert-level diagnostics.This not only avoids the unit for maintenance personnel changes affecting the maintenance standard units,but also easy to make a general maintenance staff in case of breakdown,can also be prompted through the expert system, and gradually find out the cause of the malfunction,and finally troubleshooting.Exactly speaking, a large number of aviation piston engine failure data and maintenance experience to be expressed in the form of fault tree, while the fault tree is summaried and refined to produce an aviation piston engine expert system.It can finalize the location and cause of the failures and put forward the maintenance recommendations so that ultimately bring about the engine fault entirely ruled out.更多还原