Abstract: The solid-shell transient elements established before will cause an unrealistic high level of stress because of using a wrong expression for the initial thermal strain and restricting the Poisson's effect for the material in the element. To solve both problems, in this paper, a new formulation for the 15-node solid-shell transient element is given by choosing the shell strain-stress state as the strain-stress state of the transient element. The expression for the coordinate, the displacement, the strain and the stress in the local coordinate system, the stiffness matrix, and the load vector are derived in detail. Numerical examples for the turbine rotor blades of two aeroengines are given at the end of the paper. The results of one of the examples are compared with the corresponding experimental results. These examples have shown the effectiveness of this new type of transient element. The present technique can also be applied to other types of transient elements and methods dealing with the solid-shell combined structures.

Key words: solid-shell transient element, thermal strain, Poisson's effect, shell strain-stress state