Characterizing vibrational behavior of a large airship based on scaled model test and analysis

Purpose - This study aims to assess the vibrational behavior of a large transport airship based on finite element (FE) simulation and modal testing of its scaled model. Design/methodology/approach - A full-size parametric FE model of the airframe was established according to the structural layout of the composite beam-cable airframe of the airship, and vibrational analysis of the airframe was conducted. The influence of cable pre-tension load on the inherent properties of the airframe was investigated. Based on the simplification of the full-size FE model, scaled numerical and test models of the airframe, with a geometric scale factor of 1:50, were established and built. Findings - The simulation and test results of the scaled models indicated that the mode shapes of the full-size and scaled models were similar. The natural frequencies of both the full-size and scaled models complied with the theoretical similarity relation of the frequency response. Originality/value - This study demonstrated that the vibrational test results of the scaled model with very large scaling can be used to characterize the modal properties of the beam-cable airframe of a large transport airship.