Research On Performance Parameters Law Of Aircraft Engine In Fault State

In recent years,the civil air transport industry has entered a period of rapid development,and the world's air transport volume will have leaps and bounds.Aero-engines,being the "heart" of aircraft,are widely used in military and civilian aircraft because of their advantages such as high power,smooth operation,easy installation and maintenance.However,the aeroengine is a high-tech complex thermomechanical system,and its long-term work in the harsh environment of high temperature,high pressure and alternating heat load,the engine performance degradation or failure during operation,thus affecting the aircraft Safe operation and safety of human life and property.With the advancement of aeroengine technology and continuous improvement of engine performance and reliability,the research on performance analysis and fault diagnosis technology is also continuing to advance.Especially in the past 20 years,with the rapid development and popularization of computer technology and computational mathematics,computational fluid dynamics,computational solid mechanics,computational heat transfer,computational combustion,and artificial intelligence algorithms have made considerable progress.A deep understanding of the complex physical mechanisms inside the engine,optimization design,performance analysis,regression prediction,troubleshooting and engine health management plays an important role.Aeroengine performance analysis and status monitoring and fault diagnosis technologies have gradually developed into a complete synthesis.Engineering disciplines.Therefore,it is necessary to keep abreast of the running status of the engine,analyze the performance status of the engine in time and accurately,and determine the position of the fault and the cause of the fault.In this way,the engine can be repaired in time,the utilization rate of the engine can be increased,the maintenance cost of the engine can be reduced,the flight safety of the aircraft and the economic benefits of the enterprise can be guaranteed.In this paper,the civil dual-axis turbofan engine as the research object,its fault types,the performance parameters of the variation and model-based fault identification were studied.First of all,it introduces the main types of faults in each unit of the engine,and analyzes its causes and failure mechanisms in-depth.Secondly,according to the aerodynamic working process of the engine,the small deviation theory is applied to deal with the small deviation of the thermodynamic equation of each unit body.The small deviation model of each unit body is obtained.Based on the balance of flow rate and the pressure balance,the mathematical matrix model of the relationship between the performance of engine components and the performance parameters of the whole unit is established based on the above unit cell models.At last,the change law of the performance parameters of the engine is researched by using the model.The fault parameters of the engine are identified by the similarity method of cluster analysis,and the type of the engine fault corresponding to the measured parameter deviation is determined.