Dual-stage uncertainty modeling and evaluation for transient temperature effect on structural vibration property

In practical engineering, the changing structural temperature distribution has been considered as an important factor influencing the structural vibration property. By treating the uncertainties in material properties, boundary conditions and external loads as interval variables, this paper proposes a dual-stage uncertainty analysis framework to evaluate the variation of structural natural frequency associated with transient non-uniform temperature distribution. Based on the subinterval dividing strategy, a modified interval vertex method is firstly proposed to predict the uncertain temperature field. As the material mechanical properties are temperature dependent, the components with different temperatures are consequently employed to discrete the structural model. Then by using the Taylor series, an interval perturbation method is developed to solve the generalized eigenvalue problem for the natural frequency prediction. By introducing the traditional Monte Carlo simulations as reference, a 3D plate structure with uncertain parameters is adopted to verify the proposed method.