Prediction of Statistical Energy Analysis Parameters in Thermal Environment

Abstract

An algorithm is presented to predict the statistical energy analysis (SEA) parameters of structures in a thermal environment. An energy flow model considering thermal effects is established by the finite element method, and the SEA parameters of the structure under a thermal environment are obtained by a power injection method. The proposed algorithm is applied to a simply supported L-shaped folded plate under rain-on-the-roof excitation. The accuracy of proposed method is verified by the travelling wave approach, and the influence of thermal effects on the SEA parameters is further investigated. The results show that, when only the effect of temperature-dependent material properties is considered, both the coupling loss factor (CLF) and the modal density have an opposite trend with the changing of the elastic modulus and shear modulus; when only the effect of additional stiffness due to thermal stresses is considered, the internal loss factor (ILF) and CLF decrease with the increase of temperature; when both the effects of the temperature-dependent material properties and the additional stiffness due to thermal stresses are taken into account, the ILF and CLF decrease with the increase of temperature. Furthermore, when the structure is exposed to a nonuniform thermal environment, the modal density, ILF, and CLF will decrease with the increase of the temperature gradient.