Research On Design Method Of Turbine Tenon/mortise

Firtree tenon/mortise, which is used in aero-engine turbine to join a blade with the rotating disc, works under very complex conditions and often breaks off, therefore it is important to research its design method. This paper focuses on the design method of firtree tenon/mortise, the three-tooth firtree joint model is established with parametric method by UG software. Based on analyzing the effects of primary geometrical features on the stress field, the design method of firtree joint is proposed. Double curvature curve is applied to reduce the critical stress concentration which occurs at tenon/mortise. Known features and working state of some existent joint are employed as condition, a new tenon/mortise is designed with the proposed method and compared with the available one. 3D contact stress analysis of the new structure at normal temperature is processed in ANSYS software. Considering the effect of temperature load, the analysis is further extended to the high temperature. Compared with the available one, the result indicates that the design method brought forward in this paper is effective.