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System of Rods Longitudinal Vibrations

Authors: Pavlov A.M., Temnov A.N. Published: 03.12.2014
Published in issue: #6(57)/2014  
DOI:

 
Category: Mechanics  
Keywords: longitudinal vibrations, eigen modes and frequencies, rods model, energy conservation principle, selfadjoint operator, vibration spectrum, POGO

In questions of dynamics of liquid fuel rockets the problem of motion stability for this rocket has an important role with the appearance of longitudinal elastic vibrations. An occurrence of such kind vibrations can evoke self-vibrations which may cause rapid destruction of the rocket in case of rocket instability within longitudinal direction. The problem on longitudinal vibrations of the liquid fuel rocket based on the packet scheme has been formulated using package rods as computational model. It is assumed that the liquid in the rocket tanks is "frozen", i.e. proper motions of the liquid are not included. For this problem energy conservation principle was formulated and its operator staging is given. There is a numerical example, for which the frequencies have been determined, forms of Eigen vibration were built and analyzed.

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