Contact Characteristics Analysis Of Dovetail Attachment And Optimization Of Disc

Aero-compressor is high complex and sophisticated thermal machinery. Its performance has a direct impact on the aircraft’s performance, reliability and economical efficiency. In recent years, the major aero-compressor mechanical failures which happened in China occurred as high as80%above. Therefore, the technological development level of aviation is determined by the research and development of aero-compressor level.The dovetail attachment in blade-disk assemblies of aero-compressor is the typical contact type. Because of the blades of compressor having complex loadings, which including blade’s centrifugal force, aerodynamic force effects from the aerodynamic and the vibration, the dovetail and mortise not only has more serious concentration of contact stress, but also the stress state is very complicated when it works. So the dovetail attachment of aero-compressor becomes the structure which the engine troubles often happened. Statistical data shows that above20%of the aero-compressor troubles were caused by the dovetail attachment structure failures. Therefore, it is very important to consider the calculation of the dovetail attachment contact problem, the main research content are as follows:(1) Hertz contact theory and the coulomb’s law of friction were used in the analysis of the dovetail attachment contact problem. And the actual application conditions and the typical example of Hertz contact theory and the coulomb’s law of friction is how to be used in practical applications. Specific calculation was done combining with the simplified straight dovetail attachment structure(2) Comparative analysis of the dovetail attachment’s contact characteristics under different working conditions were researched. The number of stable surface grids was determined. Secondly, the contact pressure, sliding distance and contact status of the sraight and the skewed dovetail attachment under different contact variables were compared and analysed. Finally, the contact surfaces’characteristics under loadings from different working conditions were compared.(3) The contact surfaces’characteristics of the different invasion degrees and rub-ways was compared and analysed under the rub-impact between the blade and cartridge receiver.(4) Basing on HyperWorks, topological optimization analysis was used in the disc of the dovetail attachment under the given materials, loading conditions and yield strength. With the minimal quality of disc, the aero-compressor can improve the thrust-weight ratio and reach the lighten requirements.