Research On Life Rule And Maintenance Optimization Of The LYCOMING Engine Part

The domestic aviation market is growing demand for general aircraft, with the rapid development of national economy and general aviation industry in China. Meanwhile, there are a large number of planes using aero piston engines as the power plant in general aviation field. However, technical activities including maintenance and replacement of engine part are becoming more and more, with a big number of aero piston engines put into use. In recent years, the traditional empirical mode of condition based maintenance (CBM) is gradually exposing disadvantages of excessive and in adequate maintenance, it restricts seriously further playing efficiency of aero piston engine. In this thesis, according to the features of use and maintenance of the LYCOMING engine, the failure mechanism and optimized maintenance mode of typical parts are analyzed, the life rule of important life limited part (LLP) are studied. The main research work is as following:(1) Holistically, the domestic and foreign research tendency of life rule and maintenance optimization of aero engine part is presented. The failure mode of representative part of the LYCOMING engine is researched. Taking into account actual engine use and maintenance, the failure mechanism of typical part is analyzed from material performance, physical characteristics, chemical properties, system motion state and other issues of the part. And the failure analysis methods and corresponding maintenance optimization measures of typical part of LYCOMING engine are discussed.(2) The mathematical models for describing components reliability are studied. The methods of collection and analysis of fault data are illustrated by means of descriptive and inferential statistics. The process which how to determine distribution model depending on fitting data is expounded. The analysis of maximum likelihood estimation and least square estimation is discussed. The theory of χ2testing and K-S testing is given.(3) On the platform of MINITAB, the failure distribution model of engine fuel regulator, the representative component of small simple data, is figured out by least square estimation (LSE); the failure distribution model of generator, the representative component of big simple data, is figured out by maximum likelihood estimation (MLE). Moreover, the life rule of other LLPs is also explored in the LYCOMING engine. The changing tendency of reliability and air material reserve of ten LLPs from four subsystems of the LYCOMING engine are predicted. The application of reliability research conclusion is preliminary discussed.(4) The demanding for the prediction platform of LLP reliability data of the LYCOMING engine is analyzed systematically. The main module chart of the prediction platform is drawn up. The way how to realize function of the prediction platform is introduced in detail in the module chart. The realization process of the prediction platform function is illustrated with some operation interfaces. At the end, the programming process of the prediction platform is stated as well.