An equivalent approach for testing natural vibration characteristics of a planar film reflect-array in vacuum
XIE Zhong 1 HE Yanli 1 CHEN Wujun 2
1. College of Architecture and Civil Engineering, Beijing University of Technology, Beijing 100124, China；
2. Space Structures Research Centre, Shanghai JiaoTong University, Shanghai 200240, China
Abstract：In atmospheric environment,the additional mass produced by air greatly can reduce the stiffness of a planar film reflect-array to make its natural vibration characteristics have a larger error compared with those in actual vacuum environment. In order to test and verify dynamic characteristics of a planar film reflect-array,considering practical tests in vacuum environment being unmanageable and uneconomical,an equivalent approach to measure a grid film’s natural vibration characteristics in atmospheric environment neglecting the effect of additional mass produced by air to substitute those of a planar film reflect-array in vacuum environment was proposed. The numerical simulation results for natural vibration characteristics of both cases were contrastively analyzed,and the test verification was conducted using biaxial tension device and non-contact displacement dynamic collection equipment. Finally,a useful formula was obtained to calculate the equivalent natural frequencies of a planar film reflect-array in vacuum environment using the corresponding test values of a grid film in atmosphere environment.
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