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Based on Finite element method-Direct boundary element method (FEM-DBEM) and Finite element method-Indirect boundary element method (FEM-IBEM) approach, the bearing cylinder-skin structural-acoustic coupling models considering onlyinternalorexternalacoustic field and both inside and outside acoustic field are established. The structural-acoustic coupling analysis under random base excitation is researched. Further, the coupled effect of internal/external acoustic field and structural-acoustic coupling on the inherent characteristics and dynamic response is analyzed with the emphasis on. Results show that coupled effect results in the decrease of its nature frequencies, but has no effect on the modal shape. Single acoustic field effect results in the increase of the nature frequencies more than both inside and outside acoustic field effect. The coupled effect also results in the overall decrease of dynamic response, but causes increase of the dynamic responsein the places where is parallel to the direction of excitation. In addition, influence of internal acoustic field on the dynamic responseis greater than the external acoustic field. [ABSTRACT FROM AUTHOR]

Specification of spacecraft mechanical environment is the essential input for design and testing of spacecraft and its payloads, which could directly affect the level of the spacecraft design. Along with the rapid development of space industry, higher payload capability is demanded for modern spacecraft due to the new missions, whereas the mechanical environment analysis and specification determination have been the bottlenecks for payload ratio increase of spacecraft in China. In this paper, a research review of the mechanical environment prediction methods, finite element modeling & model updating and specification determination methods, which are the key techniques related to the mechanical environment analysis, is presented. In the end, according to the requirement of the domestic space engineering, the main research directions in the spacecraft mechanical environment analysis and specification determination are emphasized. [ABSTRACT FROM AUTHOR]