In order to resolve the stress concentration of the holes on engine disks

a geometry model of turbine disk non-circular hole was established and applied to a turbine disk flange.The contour of this model consisted of eight biaxial symmetry arcs to ensure smooth connection and bolts assemblage.The geometry of turbine disk hole was improved and optimized with the non-circular hole

using the maximum first principal stress as objective function.The optimization results show that the maximum first principal stress on the non-circular bolt hole inner surface is reduced by 14.8% along with remarkable drop of the stress concentration.The results of design variables' sensitivity show that the sizes of transition arcs connected with main arcs have significant influence on hole edge stress concentration.