Ming Zhang1 , Rui Jiang2 , Hong Nie3
1, 2Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
3State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing, China
Journal of Vibroengineering, Vol. 17, Issue 2, 2015, p. 587-601.
Received 14 July 2014; received in revised form 2 September 2014; accepted 1 October 2014; published 31 March 2015
Copyright © 2015 JVE International Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
In view of large loads being needed to protect the axial from the shock situation under small displacement and deformation, a new fluid bag for axial protection was designed in Abaqus. Hydrostatic fluid elements were used to simulate fluid. Interaction between the fluid and bag was simulated with the hydrostatic theory. Based on the finite element theory, the axial stiffness of fluid bag was calculated. The results show that the stiffness had good linearity. The difference between the simulation and experiment results is small, proving the correctness of simulation. The effects of initial bag pressure on the stiffness were discussed. The results indicate that different initial pressures have few impacts on the stiffness as well as tendency of bag pressure variations. Then the effects of bag material properties and fluid bulk modulus on the stiffness were discussed. The results show that both of them are the key factors determining the stiffness. The effects of fluid bag on the stress of a mechanism under axial shock load were discussed. The results show that the fluid bag has a good performance for axial protection.
Keywords: fluid bag, axial stiffness, factors affecting the stiffness, axial protection.