Optimization design method for twin-web turbine disk/tenon structure based on static strength and life reliability

In order to guarantee the fatigue life reliability of twin-web turbine disk/tenon, a method of optimization design based on static strength and life reliability was put forward. With introduction of the optimization strategy of the disk's axisymmetric model and the turbine disk/tenon three-dimensional model in turn, the static strength optimization was in progress. According to the material stress-life data, the life reliability of turbine disk/tenon structure already meeting the static strength criteria was analyzed in consideration of the size effect. Stress-life curves of different zones for a given reliability were established. The point stress criterion of the static strength optimization was modified according to the stress-life curves. On the premise that the disk wasnt broken, the complex optimization process based on life reliability was simplified based on stress standard. A typical example showed that the static strength optimization result could not meet the design requirements of life reliability. Through the life reliability optimization design, the structural life was prolonged by 47.28% and met the design requirement of reliability life. And on the basis of the turbine disk/tenon mass reduction by 16.66% during the static strength optimization, the total mass reduced 3.43% in life reliability optimization again. Under the conditions of ensuring the accuracy of the optimization.The method can significantly improve the optimization efficiency, enabling convenient engineering applications.